Kpk Mdcat Mock Paper 5 — Solved Past Paper with Answers

Q1. Choose the word most similar In meaning to the capitalized one: INEVITABLE:

• A. Doubtful
• B. Deny
• C. Unexpected
• D. Certain✓
• E. Unusual

Explanation: Inevitable means something which is bound to happen or is very certain, undoubtful, and clear.

Q2. Choose the correct spelling:

• A. Exantuated
• B. Axantuated
• C. Accenchuated
• D. Accentuated✓

Explanation: To "accentuate" means to “make more noticeable and prominent” and its correct spelling is given in Option D.

Q3. ‘She always carried an umbrella’. The sentence indicates _ tense.

• A. Present Simple
• B. Past Simple✓
• C. Past Perfect
• D. Present Perfect

Explanation: The sentence indicates simple past tense as the verb used here is “carried”.

Q4. Choose the correct spelling of the word:

• A. Something✓
• B. Somthing
• C. Sumthing
• D. Sumthin

Explanation: The correct spelling is 'something'.

Q5. Find errors in the following sentence:

• A. The captain, along with his team
• B. Are practising very hard✓
• C. For the
• D. Forthcoming matches.

Explanation: The captain's team is a singular term. If the noun is singular, use 'is'. If it is plural or there is more than one noun, use 'are'. For example, The cat is eating all of his food. The cats are eating all of their food. Therefore, the error lies in the statement "are practicing very hard". Instead, it should be "is practicing very hard".

Q6. Select the option which fits appropriately in the blank: I am in London this Summer, I _ English.

• A. Learn
• B. Learns
• C. Am learning✓
• D. Learning

Explanation: Since the sentence is in continuous and present tense, the verb will have '-ing' added so it will end up as 'am learning'.

Q7. Sameer _ in the park every day.

• A. Run
• B. Runs✓
• C. Running
• D. Walk

Explanation: Run - This is the base form of the verb, but it does not agree with the subject "Sameer" because it is not in the third-person singular form. Therefore, this is not the correct answer.Runs - 3rd person singular present tense of run is runs. Running - This is the present participle form of the verb. While it is grammatically correct, it does not fit in the sentence structure as it cannot be used as the main verb of the sentence.Walk - This is a completely different verb and does not agree with the subject "Sameer" in the sentence. Therefore, this is not the correct answer.

Q8. My parents _ near Lahore.

• A. Living
• B. Are living
• C. Lives
• D. Live✓

Explanation: Option A : "Living near" is incorrect as it does not agree with the subject-verb agreement.Option B : "Are living" is also incorrect as it uses the present continuous tense, which is not suitable for describing a present state.Option C : "Lives" is incorrect as it is in the third-person singular form, which does not agree with the subject "my parents," which is in the plural form Parents is a plural noun so the verb used should be singular.

Q9. Sumafra was surprised when her boss didn't _ the dinner that they had at the restaurant.

• A. Buy
• B. Pay
• C. Pay for✓
• D. Spend

Explanation: "Buy" is not the best answer because it is not clear what Sumafra's boss would have bought. Moreover, the context suggests that they have already eaten at the restaurant."Pay" could be a possible answer, but it is not specific enough. "Pay" could mean paying for something else or settling a previous debt, so it is less accurate than option C. 'For' must be used when the reason or purpose is a noun. "Spend" is not a suitable answer because it does not specify who is spending the money. Additionally, it is not clear what the money is being spent on.

Q10. The two machines _ considerably. One has an electric motor, and the other one runs on oil.

• A. Different
• B. Differentiate
• C. Differ✓
• D. Difference

Explanation: As verbs, the difference between differ and differs is that differ is not to have the same traits, characteristics, while differs, is (differ).

Q11. Choose the correct sentence:

• A. Samar bought an apple, an orange and an pear.
• B. Samar bought an apple a orange and a pear.
• C. Samar bought an apple, an orange, and a pear.✓
• D. Samar bought a apple, an orange and a pear.

Explanation: Option A: This sentence is missing a comma before "and." It should be "an orange, and a pear." The absence of the comma makes the sentence grammatically incorrect.Option B: This sentence is also missing a comma before "and." Similar to option A, it should be "an orange, and a pear." The lack of a comma makes this sentence grammatically incorrect as well.Option C: This sentence is correctly punctuated with commas. It uses the comma before "and" when listing three items. Each item in the list is separated by a comma, and the final comma (known as the Oxford comma) is used before "and." This option is grammatically correct.Option D: Similar to options A and B, this sentence is missing a comma before "and." It should be "an orange, and a pear." The absence of a comma makes this sentence grammatically incorrect.

Q12. Select the nearest correct meaning of the word: 'Unburdened'.

• A. Hindered
• B. Extort
• C. Free✓
• D. Encumbered

Explanation: ‘Unburdened’ means someone who is not burdened.

Q13. We still haven't come _ with an interesting theme for the advertising campaign.

• A. On
• B. In
• C. Up✓
• D. Down

Explanation: Come up is an expression used to say: to produce, especially in dealing with a problem or challenge.

Q14. Complete the following sentence: My watch is five minutes _.

• A. Behind✓
• B. Before
• C. Slow
• D. Early

Explanation: In the given sentence, a comparison is being made between the actual time and the time of the watch, hence behind would be used to connect the differences. This is because both processes are continuous. Therefore, option A is correct.

Q15. In the following sentence, demonstrate the correct use of the subject-verb agreement: Some of the books on the table _ to me.

• A. Belong✓
• B. Belonging
• C. Belongs
• D. Was belong

Explanation: As it is a general statement showing possession and no helping verb is used, the sentence indicated is in the present tense. The subject ‘Some of the books’ is plural as it indicates the number of books more than one, hence the verb used in the sentence should not contain an ‘s’. This is why ‘belong’ is the correct option. Therefore option A is the correct answer.

Q16. What part is wrong in the following sentence? You must had a kind and gentle heart if you want to become a successful doctor.

• A. You must had✓
• B. A kind and gentle heart
• C. If you want
• D. To become a successful doctor.

Explanation: Had is the wrong verb form used in the sentence. Had is the second form of the word ‘have’. Since the tense used is simple present, so have would’ve made the sentence correct.

Q17. Choose the correct sentence from the following options:

• A. The government should accrue taxes for strengthen the economy of the country.
• B. The government should accrue taxes in strengthen the economy of the country
• C. The government should accrue taxes to strengthen the economy of the country.✓
• D. The government should accrue taxes by strengthen the economy of the country.

Explanation: By comparing all four sentences ,you notice there is only one difference i.e. PREPOSITION and for fact the best suited is 'to strengthen'.

Q18. The excretion of hypertonic urine in humans is associated best with the:

• A. Glomerular capsule
• B. Proximal convoluted tubule
• C. Loop of Henle✓
• D. Distal convoluted tubule

Explanation: Hypertonic Urine means there is a higher solute concentration than the body fluid (the solution has more osmotic pressure; water moves in by osmosis). This means maximum water has been reabsorbed. Despite Option B, Option C, and Option D, playing a role in water reabsorption, the main site where water reabsorption occurs is the Loop of Henle. Glomerular Capsule (or the Bowman capsule, is a cup-like sac at the beginning of the nephron that is involved in the filtration of the blood coming into the kidney. The proximal Convoluted Tubule is present after the Bowman's capsule while the Distal convoluted tubule is present after the loop of Henle. The proximal Convoluted Tubule is the site where Sodium ions are reabsorbed while the Distal convoluted tubule is where the body carries our processes to maintain the body acid-base concentration. On the other hand, the Loop of Henle is associated with both the solute and water reabsorption using the counter-current multiplier, which involves the usage of energy to generate an osmotic gradient that enables the reabsorption of water from the filtrate and into the blood, producing concentrated urine.

Q19. In humans, the temperature regulation control center is located in:

• A. Kidneys
• B. Brain✓
• C. Lungs
• D. Liver

Explanation: The body's temperature control center is the hypothalamus which itself is part of the brain. The hypothalamus via a network of thermoreceptors can sense when you are unusually hot. If so then the hypothalamus proceeds to send signals to your sweat glands to make you sweat and cool you off. When the hypothalamus senses that you're too cold, it sends signals to your muscles that make you shiver and create warmth. This is called maintaining homeostasis. The kidneys help to maintain homeostasis by regulating the concentration and volume of body fluids. Lungs are essential for the constant gaseous exchange of O2 and CO2. The liver plays an important role in the metabolism of nutrients in your body, detoxifying drugs, storing glycogen, synthesizing plasma proteins, etc. Hence, Option B is correct.

Q20. As an excretory organ, liver:

• A. Detoxifies many chemical poisons
• B. Produces ammonia for excretion by the kidneys
• C. Produces urea and uric acids from the nitrogen of amino acids
• D. All of the above✓

Explanation: The liver has numerous functions in the human body, let's discuss each option one by one. A: The liver is an organ that comes into play after consumption of alcohol, as you can remember excess alcohol consumption can result in liver cirrhosis, where scarring occurs on the liver after continuous exposure to high amounts of alcohol. B&C: The urea cycle (also known as the ornithine cycle) occurs in the mitochondria of liver cells and results in the conversion of poisonous ammonia (NH3) to urea ((NH2)2CO) which is then excreted in the urine. All the above-mentioned metabolites are removed from the human body either directly (as in urea) or indirectly by further conversion into another substance. Hence, Option D is correct.

Q21. The active uptake of sodium in the ascending limb or thick loop of Henle is promoted by the action of:

• A. Aldosterone✓
• B. Thyroxine
• C. ADH
• D. Cortisone

Explanation: As a general principle, Sodium-Ion Concentration in the body is maintained by the hormone Aldosterone. The descending loop of Henle's loop is permeable to water. Water can be reabsorbed from the fluid inside the loop of Henle to the surrounding. The ascending loop of Henle's loop is impermeable to water. Sodium chloride is actively transported from the thick portion of the ascending limb without accompanying water. Hence, Option A is correct.Thyroxine is the main hormone secreted into the bloodstream by the thyroid gland. It plays vital roles in digestion, heart and muscle function, brain development, and the maintenance of bones. Thyroxine is produced by the thyroid gland, which stimulates the basal metabolic rate. It controls the speed at which oxygen and food products react to release energy for the body to use. Thyroxine plays an important role in growth and development. Thyroxine levels are controlled by negative feedback. The anti-diuretic hormone helps to control blood pressure by acting on the kidneys and the blood vessels. Its most important role is to conserve the fluid volume of your body by reducing the amount of water passed out in the urine.Cortisone is a steroid drug. It helps decrease swelling and inflammation in your body.

Q22. Coelom that develops from the archenteron as outpouching is?

• A. Pseudocoelom
• B. Schizocoelom
• C. Enterocoelom✓
• D. Both a and b

Explanation: 'Enterocoelom' is a coelom formed from the wall of the embryonic gut or enteron as hollow outgrowths. 'A' is not the answer because 'pseudocoelom' is the space between the body wall and the digestive tract and is not lined by the coelomic epithelium. 'B' is not the answer because the splitting of the mesoderm causes the formation of 'schizocoelom'.

Q23. Enzymes work by which of the following?

• A. Increasing the activation energy.
• B. Reducing the activation energy.✓
• C. Making exergonic reactions endergonic.
• D. Making endergonic reactions exergonic.

Explanation: Enzymes work by reducing the activation energy required for a chemical reaction to occur. The activation energy is the minimum energy input needed for reactant molecules to transform into products during a chemical reaction. It represents the energy barrier that must be overcome for the reaction to proceed. Enzymes facilitate reactions by providing an alternative pathway with a lower activation energy. The active site of an enzyme interacts with the substrate (reactant), bringing the reactants into close proximity and allowing the reaction to occur more easily. This reduction in activation energy accelerates the rate of the reaction and makes it more favorable under physiological conditions.

Q24. The process of determining the locus for particular biological traits includes?

• A. Replication
• B. Recombination
• C. Gene mapping✓
• D. None of these options is correct

Explanation: Option A: Replication refers to the process of copying DNA during cell division and is not directly related to gene mapping.Option B: Recombination is the process by which genetic material is exchanged between chromosomes during meiosis, and can be used to map genes to particular regions of a chromosome. However, it is not the sole process involved in gene mapping.Option C: Gene mapping describes the methods used to identify the locus of a gene and the distances between genes. Gene mapping can also describe the distances between different sites within a gene. The essence of all genome mapping is to place a collection of molecular markers onto their respective positions on the genome. Option D: As explained above this option is incorrect.

Q25. The attraction between water molecules and the cell wall of xylem is termed as:

• A. Cohesion
• B. Tension
• C. Adhesion✓
• D. Imbibition

Explanation: Option A: Cohesion refers to the attraction between water molecules themselves, which allows them to stick together and form a continuous column in the xylem. Option B: Tension refers to the force that pulls water up through the xylem, which is caused by transpiration at the leaves. Option C: Adhesion is a molecular attraction between "unlike" molecules. In the case of the xylem, adhesion occurs between water molecules and the molecules of the xylem cell walls. Cohesion is a molecular attraction between "like" molecules. In water, cohesion occurs due to hydrogen bonding between the water molecules.Option D: Imbibition refers to the process by which a solid absorbs water, such as a seed swelling when it takes up water.

Q26. Gametes in animals are produced by which of the following?

• A. Mitosis
• B. Meiosis✓
• C. Fission
• D. All of these

Explanation: Only meiosis is the type of cell division that will produce haploid number of chromosomes (n). Gametes contain haploid (n) number of chromosomes. Mitosis produces diploid chromosomes and fission does not occur in animals.

Q27. A neural pathway that controls an action reflex is called:

• A. Nerve cell
• B. Reflex arc✓
• C. Receptor cells
• D. Mixed nerve

Explanation: Option A: A nerve cell is a basic unit of the nervous system that transmits signals throughout the body.Option B: A reflex arc is a neural pathway that controls a reflex. In vertebrates, most sensory neurons do not pass directly into the brain but synapse in the spinal cord. This allows for faster reflex actions to occur by activating the spinal motor neurons without the delay of routing signals through the brain.Option C: Receptor cells are specialized cells that respond to specific stimuli such as light, sound, or chemicals. Option D: A mixed nerve is a nerve that contains both sensory and motor fibres.

Q28. In all plants, the major sites of photosynthesis are?

• A. Leaves✓
• B. Stems
• C. Roots
• D. Branches

Explanation: Photosynthesis is the process by which plants convert water and carbon dioxide to glucose and ATP. It occurs in the presence of sunlight and chlorophyll.

Q29. The set of all genes in any population is termed as?

• A. Population tool
• B. Species tool
• C. Gene pool✓
• D. All of these options are correct

Explanation: The gene pool is the set of all genes, or genetic information, in any population, usually of a particular species. This also proves to be the basic level at which evolution occurs.

Q30. Smooth muscles, cardiac muscles, and organs are regulated by which of the following?

• A. Central nervous system
• B. Parasympathetic nervous system
• C. Sympathetic nervous system
• D. Autonomic system✓

Explanation: Smooth muscles, cardiac muscles and organs are controlled by the autonomic nervous system, as they donot require conscience control and are involuntary actions. Autonomic nervous system and the somatic nervous system are part of the peripheral nervous system. The somatic nervous system controls all conscious activities, for example the movement of skeletal muscles. The autonomic nervous system allows for tight unconscious control of respiratory and heart rate and other critical systems of the body. Hence option D will be the correct option.

Q31. The main target in the prevention of lung cancer is eliminating the _.

• A. Tobacco smoking✓
• B. Chemicals
• C. Pollutants
• D. Mutagens

Explanation: Tobacco cigarettes contain nicotine and tar which acts as a carcinogen. Carcinogens are cancer causing chemicals. The most common and wide spread cause for lung cancer is smoking. Smoking especially in young adults is the most potential threat of lung cancer. Chances of lung cancer are ten times more in a person who smokes or lives in smoky areas as compared to those who dont. It is now estimated that 90% lung cancer is caused by smoking.

Q32. Which one of the following muscles are considered as “Voluntary muscles”?

• A. Smooth muscles
• B. Cardiac muscles
• C. Skeletal muscles✓
• D. Glandular muscles

Explanation: Functionally, our body has three categories of muscles i.e. Smooth, Cardiac, and Skeletal which are then further classified as voluntary and involuntary muscles. Voluntary muscles are muscles under conscious control i.e. they be controlled at will or we can choose when to use them. A good example of voluntary muscles is skeletal muscles which are responsible for the movement of body parts and locomotion. Hence, Option C is correct. On the other hand, involuntary muscles are those which are not under our conscious control. Examples of involuntary muscles include Smooth and Cardiac Muscles. Cardiac muscles contract on their own due to the self-excitable SA Node. Similarly, smooth muscles like glandular muscles contract automatically and release hormones when required.

Q33. The term ‘cell’ was given by

• A. Leeuwenhoek
• B. Robert Hooke✓
• C. Flemming
• D. Robert Brown

Explanation: The origins of the word 'cell' in the 1660s, Robert Hooke looked through a primitive microscope at a thinly cut piece of cork. He saw a series of walled boxes that reminded him of the tiny rooms, or cellula, occupied by monks.

Q34. The upward movement of sap by the xylem is:

• A. Ascent of sap✓
• B. Plasmolysis
• C. Deplasmolysis
• D. Guttation

Explanation: "The explanation for this question will be added soon!".

Q35. Which of the following wavelength is absorbed maximum for photosynthesis?

• A. 660 nm
• B. 680 nm
• C. 440 nm✓
• D. 700 nm

Explanation: Since chlorophyll absorbs maximum energy from the blue and red wavelength, blue light is absorbed maximum for photosynthesis than any other light and this color also comes first in the spectrum. A, B, and D are not the answers because of the above reason.

Q36. What are the subunits of capsids?

• A. Capsomere✓
• B. Flagella
• C. Hyphae
• D. Septa

Explanation: Capsomeres are tiny subunits that make up the protein coat, referred to as the capsid. Capsomeres are known as capsid subunits, which are the outer protective covering of proteins that protect the virus's genetic material. TMV is also known as the tobacco mosaic virus. It is a type of single-stranded RNA virus.

Q37. Who discovered the bacteria causing tuberculosis and also developed various techniques of media preparation and maintenance of pure culture?

• A. Robert Koch✓
• B. Louis Pasteur
• C. Alexander Fleming
• D. Antonie van Leeuwenhoek

Explanation: Fact.

Q38. The ability of an individual to pass on its phenotype to future generations is known as:

• A. Fitness✓
• B. Heritability
• C. Limited environmental resources
• D. Overproduction of offspring
• E. Phenotypic variation

Explanation: Option A: Natural selection acts upon the phenotype and not on the genotype. Even with a large variation in genotypes within a population, natural selection will only occur if the genetic variations result in physical, chemical, or behavioral expressions (phenotypes) in individuals. One of the bases of natural selection is the ability of an individual to pass on its phenotype to future generations which is known as fitness. Thus, the correct answer is Option A. Option B: Heritability refers to the extent to which a trait is determined by genetics rather than environmental factors. Option C: Limited environmental resources refer to the fact that resources such as food, water, and shelter are finite, and organisms must compete for them to survive. Option D: Overproduction of offspring is a concept that describes the reproductive strategy of many organisms, where they produce more offspring than can survive to adulthood. Option E: Phenotypic variation refers to the range of observable traits among individuals of a species.

Q39. Assymetrical body is a feature of phylum _.

• A. Annelida
• B. Arthropoda
• C. Porifera✓
• D. Cnidaria

Explanation: An asymmetrical body is a body that has no symmetry, i.e., that cannot be cut into two equal mirror images. The only phylum that has an asymmetrical body is phylum Porifera, the sponges.

Q40. A condition with abnormal amount of fats is called?

• A. Anorexia
• B. Botulism
• C. Piles
• D. Obesity✓

Explanation: Obesity is a medical condition in which excess body fat has accumulated to the extent that it may have an adverse effect on health.

Q41. The loss of water from the aerial parts of the plant is known as:

• A. Photosynthesis
• B. Transpiration✓
• C. Reproduction
• D. Respiration

Explanation: Transpiration is the process of the release of water vapor from aerial parts, such as leaves, stems, and flowers.

Q42. Which method from the following is an example of asexual reproduction?

• A. Sporulation
• B. Fission
• C. Apomixis
• D. All of these options are correct✓

Explanation: Asexual reproduction is a type of reproduction that involves only one parent, and the offspring produced are genetically identical to the parent. This process does not involve the fusion of gametes (sex cells) and does not contribute to genetic diversity. Asexual reproduction occurs in various forms across different organisms, including bacteria, fungi, plants, and some animals. Methods of asexual reproduction are fission, sporulation, budding, vegetative propagation, artificial propagation, parthenogenesis and apomixis etc.

Q43. Protein contains _.

• A. Inorganic bonds
• B. Peptide bonds✓
• C. Glucosidic bonds
• D. Covalent bonds

Explanation: The basic unit of protein are amino acids. There are approximately 20 types of amino acids found in our body. These amino acids are linked together via peptide bonds. Peptide bond between two amino acids are formed between the carbon of the carboxylic acid group and the nitrogen of the amino group by the removal of water. The sequence of amino acid, controls the type of protein made.

Q44. The name animal is derived from what word?

• A. Aname
• B. Anemia
• C. Anima✓
• D. None of these options is correct

Explanation: The word "animal" comes from the Latin word, anima, meaning 'having breath', 'having soul' or 'living being'. The biological definition includes all members of the kingdom Animalia.

Q45. The enzyme in breast milk that causes the coagulation of milk or forms precipitates of milk is:

• A. Rennin✓
• B. Trypsin
• C. Amylase
• D. Lipase

Explanation: Rennin, also known as chymosin, is an enzyme that plays a key role in the coagulation of milk proteins, particularly casein. It is commonly found in the stomach lining of young mammals, including human infants. The primary function of rennin is to curdle or coagulate milk, forming a semisolid mass. This coagulation is important for the digestion and absorption of milk proteins in the stomach.

Q46. Among the most abundant biomolecules, _ is the most abundant one on earth.

• A. Proteins
• B. Carbohydrates✓
• C. Lipids
• D. Vitamins

Explanation: Carbohydrates (example cellulose, starch, glycogen, glucose, fructose etc) are the most abundant biomolecules on earth. The carbohydrates are produced by the reduction of atmospheric carbon dioxide with the help of light energy in the process of photosynthesis.

Q47. Enzymes that are functioning within the cell are called:

• A. Endoenzymes✓
• B. Exoenzymes
• C. Holoenzymes
• D. Both A & C

Explanation: Endoenzymes are enzymes that act within the cell, and their catalytic activity is confined to the interior of the cell. They are involved in intracellular processes, catalyzing reactions within the cell's cytoplasm or organelles. Enzymes involved in glycolysis, the Krebs cycle, or other metabolic pathways taking place inside the cell are considered endoenzymes.

Q48. In which model do proteins float in membrane-like iceberg in sea:

• A. Lock and key model.
• B. Induced fit model.
• C. Fluid mosaic model.✓
• D. Lotka volterra model.
• E. All of these.

Explanation: As per the fluid mosaic model cell membranes have proteins as icebergs in a sea of lipids (lipid). Hence option C is correct.

Q49. “Zymase”- a group of 14 enzymes, used in the fermentation of starch, is present in:

• A. Bacteria
• B. Yeast✓
• C. Fungi
• D. Algae
• E. Virus

Explanation: Zymase is an enzyme complex that catalyzes the fermentation of sugar into ethanol and carbon dioxide. It occurs naturally in yeasts. Zymase activity varies among yeast strains. Zymase is also the brand name of the drug pancrelipase.

Q50. Which of the following factors affect enzyme activity?

• A. Temperature
• B. pH
• C. Concentration of substrate
• D. Radiation
• E. All of these✓

Explanation: All of the above factors can affect enzymatic activity in the sense that; . Increasing the temperature increases the activity of the enzyme until the optimum after which the enzyme starts to denature. . Altering with pH also changes enzymatic activity. . The concentration of substrate, which increases with the increase in the concentration of the substrate. . At higher radiation doses a marked decrease in the activities of all the enzymes was observed.

Q51. Steroids consist of _ 6 membered carbon rings and one 5 membered carbon ring.

• A. Four
• B. Three✓
• C. Two
• D. Five
• E. Six

Explanation: The steroid core structure is typically composed of seventeen carbon atoms, bonded in four "fused" rings: three six-member cyclohexane rings and one five-member cyclopentane ring.

Q52. The cell wall of most of the bacteria have a unique macromolecule called_.

• A. Cellulose
• B. Chitin
• C. Fibres
• D. Fats
• E. Peptidoglycan✓

Explanation: A cell wall is a layer located outside the cell membrane found in plants, fungi, bacteria. Plant cell is made up of cellulose, fungi cell of chitin and bacteria cell is made up of peptidoglycan.

Q53. The following reaction occurs in the human alimentary canal. What is the enzyme and the product?

• A. Option A
• B. Option B
• C. Option C✓
• D. Option D

Explanation: The enzyme that hydrolyzes starch is called 'Amylase'. The product formed by this hydrolysis is 'Maltose'.

Q54. Which of the following, which is the incorrectly paired one?

• A. Robert Hooke ... cell wall
• B. Schlelden and schwann ... cell theory
• C. Robert Brown... nucleus
• D. Watson and Crick ... DNA model
• E. Virchow... mosaic model of plasma membrane✓

Explanation: The fluid mosaic hypothesis was formulated by Singer and Nicolson in the early 1970s, not by Virchow. All others are correctly paired.

Q55. Which of the following basic structural level of proteins is indicated by an association of two alpha and two beta chains in the haemoglobin molecule?

• A. Primary structure
• B. Secondary structure
• C. Tertiary structure
• D. Quatenary Structure✓

Explanation: Two alpha chains join with two beta chains; this structure is termed as quaternary structure in terms of levels of proteins.An alpha or a beta chain itself is a tertiary structure. The alpha helix and beta pleated sheaths are secondary structures while the actual sequence of bases in a chromosome is called the primary structure.

Q56. Which one of the following are “myogenic” type of muscles?

• A. Glandular muscles
• B. Cardiac muscles✓
• C. Skeletal muscles
• D. Smooth muscles

Explanation: The three muscle types (Cardiac, Smooth, Skeletal) can be further classified into two categories i.e. myogenic and neurogenic. Myogenic means originating in or produced by muscle cells themselves. Neurogenic means originating in or produced by nerve cells or neurons. The contractions of cardiac muscle fibers are described as myogenic, since they are produced spontaneously, without requiring stimulation from nerve cells. This is solely due to the presence of the SA and AV nodes on the heart, capable of producing electrical impulses to stimulate contraction. Single-unit visceral smooth muscle is myogenic; it can contract regularly without input from a motor neuron (as opposed to multiunit smooth muscle, which is neurogenic - that is, its contraction must be initiated by an autonomic nervous system neuron). Skeletal muscle on the contrary is neurogenic since it can contract when stimulated by a motor neuron. Hence, the only correct answer is Option B.

Q57. Inactive enzyme precursors such as pepsinogen for pepsin are called as:

• A. Holoenzymes
• B. Actinases
• C. Zymogens✓
• D. Mucopolysaccharides

Explanation: A 'zymogen' or proenzyme is an inactive enzyme precursor. A zymogen requires a biochemical change such as a hydrolysis reaction revealing the active site, or changing the configuration to reveal the active site for it to become an active enzyme. 'Holoenzymes' are the active forms of enzymes. Glycosaminoglycans or mucopolysaccharides are long unbranched polysaccharides consisting of a repeating disaccharide unit. Actinases are not inactive enzymes. Thus, option 'C' is correct.

Q58. The uterus of the female reproductive system opens into the:

• A. Placenta
• B. Birth canal✓
• C. Cervix
• D. All of these options are correct

Explanation: The uterus of the female reproductive system opens into the vagina. The birth canal is the other name for the vagina. The cervix, which is the lower part of the uterus, protrudes into the upper part of the vagina. During childbirth, the cervix dilates to allow the passage of the baby from the uterus into the vagina and eventually out of the body. The vagina serves as a muscular tube that connects the uterus to the external body surface and functions in sexual intercourse, as well as the passage for menstrual flow and childbirth.

Q59. Two species can avoid competition and better use the environment's resources by occupying different _.

• A. Adaptations
• B. Polymorphism
• C. Niches✓
• D. Specialization

Explanation: The niche of an organism is the functional role that it plays within an ecosystem. Two species can avoid competition and better use the environment by occupying different niches.The niche of an organism within an ecosystem depends on how the organism responds and reacts to the distribution and abundance of these factors, and in turn how it alters the factors. For example, when resources are abundant, a population grows, although by growing, the population provides more resources for predators.

Q60. The shape of the tobacco mosaic virus is:

• A. Spring shape
• B. Rod shape✓
• C. Comma shape
• D. Spherical shape

Explanation: This is factual recall from the chapter of acellular life which states that TMV is a helical virus that appears rod shaped so option B is most suitable.

Q61. An amphibian's heart has _ chambers:

• A. Two
• B. Three✓
• C. Four
• D. Five

Explanation: From an evolutionary perspective, amphibians are between fishes and reptiles i.e. more developed than fishes and less developed than reptiles. Amphibians have 3 chambers, more than fishes but less than reptiles.

Q62. Amphibians live on:

• A. Water
• B. Water and land✓
• C. Land
• D. Air

Explanation: Amphibians have gills as well as lungs which make it possible for them to live on both water and land.

Q63. Germ theory was presented by:

• A. Robert Koch✓
• B. Antonie van Leeuwenhoek
• C. Robert Hooke
• D. Robert Brown

Explanation: Proposing the germ theory of disease was the crowning achievement of the French scientist Robert Koch. Robert Hooke discovered the Law of Elasticity (or Hooke's Law) and did a huge amount of work on cell theory. Robert Brown used a microscope to describe the nucleus of a cell. He also developed the idea of what is now called the Brownian motion which explained the random movement of minute particles in a fluid.

Q64. Which of the following bacteria are without a cell wall?

• A. Mycoplasma✓
• B. Gram positive bacteria
• C. Gram negative bacteria
• D. Archaeo bacteria

Explanation: Mycoplasmas are spherical to filamentous cells with no cell walls.

Q65. Binomial nomenclature was proposed for the first time by:

• A. Charles Darwin (1859)
• B. Rudolph virchow (1855)
• C. Louis Pasteur (1862)
• D. Carolus Linnaeus (1707)✓
• E. Robert brown (1773)

Explanation: Tyrannosaurus rex is probably the most widely known binomial. The formal introduction of this system of naming species is credited to Carl Linnaeus, effectively beginning with his work Species Plantarum in 1753.

Q66. Chicken pox is caused by:

• A. Hepatitis A virus
• B. Varicella zoster virus✓
• C. Influenza virus
• D. Human immunodeficiency virus
• E. Rabies virus

Explanation: Chickenpox is an infection caused by the varicella-zoster virus. It causes an itchy rash with small, fluid-filled blisters. Chickenpox is highly contagious to people who haven't had the disease or been vaccinated against it.

Q67. The viruses are:

• A. Cellular
• B. Prokaryotes
• C. Non-cellular✓
• D. Eukaryotes
• E. Visible with naked eye

Explanation: Viruses are non-cellular. They only have a genome covered by a protein coat called a capsid.

Q68. Closely related species are grouped together into _ .

• A. Families
• B. Orders
• C. Phyla
• D. Kingdom
• E. Genus✓

Explanation: Closely related species are grouped together into a “Genus”.

Q69. Which of the following is the simplest form of pathogens causing diseases?

• A. Viruses
• B. Prions✓
• C. Fungus
• D. Amoeba

Explanation: Infectious diseases are caused by pathogens, which include bacteria, fungi, protozoa, worms, viruses, and even infectious proteins called prions. The most simple and the smallest type of pathogens are prions.

Q70. Mark the one Kingdom having the most conspicuous living organisms?

• A. Monera
• B. Protista
• C. Animalia✓
• D. Plantae

Explanation: Kingdom Animalia has the most conspicous subsets of organims because theoretically they have evolved the most and are the most advanced version of evolved species.

Q71. Which of the following is NOT a viral disease?

• A. AIDS
• B. Malaria✓
• C. Influenza
• D. Chickenpox
• E. Rabies

Explanation: Malaria is not a viral disease and is caused by protozoa plasmodium. All other options are viral infections that include: AIDS caused by HIV virus, influenza caused by the influenza virus, chickenpox is caused by the Varicella-zoster virus(VZV) and rabies is caused by rabies lyssavirus.

Q72. Egg-laying mammals are called:

• A. Prototheria
• B. Protozoa
• C. Chordata
• D. Monotremes
• E. Both A and D✓

Explanation: Monotremes lay eggs and prototheria are both egg-laying mammals so the question has two correct answers. Chordata, the classification to which humans belong, are those that do not lay eggs but rather give birth to young ones. Protozoa, on the other hand, are unicellular organisms.

Q73. Organs which produce voice in birds is:

• A. Larynx
• B. Pharynx
• C. Syrinx✓
• D. Both A and C

Explanation: Organs of voice production in birds are called syrinx.

Q74. Coelom is a cavity lined by:

• A. Mesoderm✓
• B. Endoderm
• C. Epiderm
• D. Ectoderm

Explanation: Option A is correct as coelom is a fluid-filled cavity that is entirely lined by mesoderm. Options B, C, and D are incorrect as coelom is primarily lined by mesoderm only.

Q75. Which one of the following does not have intermediate host?

• A. Tapeworm
• B. Ascaris✓
• C. Liver fluke
• D. Plasmodium

Explanation: Organisms that have an intermediate host spend their lifetimes in two different organisms.

Q76. The first simplest oxygen producing organism:

• A. Methanogens
• B. Cyanobacteria✓
• C. Euglena
• D. Spirogyra

Explanation: There is suggestive evidence that photosynthetic organisms were present approximately 3.2 to 3.5 billion years ago, in the form of stromatolites, layered structures similar to forms that are produced by some modern cyanobacteria.

Q77. Bacterial pilli help in:

• A. Locomotion
• B. Conjugation✓
• C. Phagocytosis
• D. Pinocytosis
• E. Exocytosis

Explanation: Conjugative pili allow for the transfer of DNA between bacteria, in the process of bacterial conjugation. They are sometimes called "sex pili", in analogy to sexual reproduction, because they allow for the exchange of genes via the formation of "mating pairs". Locomotion is performed by flagella, phagocytosis, pinocytosis, and exocytosis by microtubules.

Q78. Which of the following organelles are present in all the bacteria?

• A. Mesosome✓
• B. Golgi bodies
• C. Mitochondria
• D. Chloroplast

Explanation: Bacteria are prokaryotes. They are made up single cell. They do not have well defined nucleus, instead they posses nucleoid as genetic material. They also lack membrane bound cell organelles like mitochondria, golgi bodies, chloroplast, etc. However, they do contains ribosomes and mesosomes in the cytoplasm. Thus, the correct answer is 'Mesosome.'

Q79. Female rabbits are:

• A. induced ovulators✓
• B. spontaneous ovulators
• C. seasonal ovulators
• D. indifferent ovulators

Explanation: This is the following solution:

Q80. Which of the following is correct in humans?

• A. Both sperm and egg contain yolk
• B. All genetic information comes from sperm
• C. Sperm contains little cytoplasm✓
• D. Fertilization commonly occurs in the uterus

Explanation: The head of the sperm contains an extremely compact nucleus with very little cytoplasm.

Q81. Only one ovary is functional at a time in:

• A. Human
• B. Eagle
• C. Chicken✓
• D. Pigeon and human

Explanation: Unlike most female animals, which have two functioning ovaries, the chicken usually has only one. The right ovary stops developing when the female chick hatches, but the left one continues to mature.

Q82. Menstrual cycle can be divided into

• A. Single cycle
• B. Two cycles✓
• C. Three cycles
• D. Four cycles

Explanation: The menstrual cycle is governed by hormonal changes. These changes can be altered by using hormonal birth control to prevent pregnancy. Each cycle can be divided into two phases based on events in the ovary (ovarian cycle) or in the uterus (uterine cycle).

Q83. Lock and Key model ws explained by:

• A. Koshland
• B. Emil Fischer✓
• C. De Duve
• D. De Duve

Explanation: Lock and Key model was given by Emil Fischer in 1890. •According to this model,the active site is a rigid structure.As one specific key can open only a single lock,in the same way a specific enzyme can transform a specific substrate into product(s). Example:Urease is the enzyme which follows this model.This model explains the specificity of enzyme action.

Q84. Name the inhibitors which can be neutralized by adding more substrate:

• A. Competitive Inhibitors✓
• B. Permanent inhibitors
• C. Non-competitive inhibitors
• D. Irreversible inhibitors

Explanation: A competitive inhibitor is a substance similar in structure to an enzyme's substrate that binds to the active site and inhibits a reaction.It blocks the active site of an enzyme and by increasing the concentration of substrate,the effect of a competitive inhibitor can be neutralized.For Example:Malonic acid is a competitive inhibitor of enzyme succinic dehydrogenase.On the other hand, the irreversible inhibitor doesn't compete with the natural active site for substrate but it combines with the site other than the active site.For Example:Cyanide action on cytochrome oxidase.

Q85. A central cavity of the kidney where urine is collected after filtration is known as:

• A. Ureter
• B. Urethra
• C. Pelvis✓
• D. Urinary Bladder

Explanation: Explanation: The central cavity of the kidney is known as the renal pelvis. From here, urine enters the ureter and is carried to the bladder. This option is not correct because the ureter is a tube-like structure that carries urine from the kidneys to the bladder. This option is also incorrect because the urethra is a tube that carries urine from the bladder out of the body. This option is also incorrect because the urinary bladder is an expandable muscular sac that stores urine until it is expelled from the body through the urethra.

Q86. Diamond and Graphite:

• A. are isotopes
• B. are isomers
• C. are allotropes✓
• D. have the same structure
• E. are equally hard

Explanation: Diamond and Graphite are allotropes of carbon. The term allotrope refers to one or more physical forms of a chemical element that occurs in the same physical state. Allotropes may show differences in chemical and physical properties.

Q87. Glass is a/an:

• A. Pure solid
• B. Supercooled liquid✓
• C. Mixture of sodium and calcium
• D. The crystalline form of Na2CO3
• E. Alloy

Explanation: Glass is sometimes called a supercooled liquid because it does not form a crystalline structure, but instead forms an amorphous solid that allows molecules in the material to continue to move. while it is also true that it’s a homogeneous mixture of sodium and calcium silicates.

Q88. The stability of ionic crystal depends principally on:

• A. High electron affinity of anion forming species
• B. Lattice energy of crystal✓
• C. Low Ionization energy of cation forming species
• D. Low heat of sublimation of cation forming solid

Explanation: The stability of ionic crystals depends on lattice energy which is released in the form of heat when two ions are brought together to form a solid. Lattice energy is the sum of all the interactions within the crystal.

Q89. Real gases behave ideally at:

• A. Low temperature and low pressure
• B. Moderate temperature and low pressure
• C. High temperature and low pressure✓
• D. High temperature and high pressure

Explanation: generally gas behaves more like an ideal gas at higher temperature and low pressure, as P.E due to intermolecular forces become less significant compared with particle kinetic energy. Real gas behaves like ideal gas at high temperature and low pressure.

Q90. The empirical formula of Glucose C6H12O6 is:

• A. C6H12O6
• B. CHO
• C. CH2O✓
• D. CH2O2

Explanation: The molecular formula for glucose is C6H12O6. The subscripts represent a multiple of the empirical formula. To determine the empirical formula, we have to divide the subscripts by the greatest common factor which in this case is 6 giving us CH2O. The molecular formula of glucose is C6H12O6 and the empirical formula of glucose is CH2O. We can derive a relation between the Molecular formula and the empirical formula of glucose. We can derive a general expression as, Molecular formula = n × empirical formula where n is a whole number. C6H12O6 = 6 × CH2O

Q91. Atomic number of C is 6 and H is 1. How many electrons are present In 1.6 grams of methane?

• A. 6.02 x 1023✓
• B. 1.204 x 1023
• C. 1.806 x 1023
• D. 2.408 x 1023
• E. 3.01 x 1023

Explanation: To determine the number of electrons in 1.6 grams of methane (CH4), we first need to calculate the number of moles of methane present:Calculate the molar mass of methane: Molar mass of C = 12.01 g/mol Molar mass of H = 1.01 g/mol Molar mass of CH4 = (4 × 1.01 g/mol) +12.01 g/mol = 16.05 g/mol Calculate the number of moles of CH4: Moles of CH4 = mass of CH4 /molar mass of CH4 Moles of CH4= 1.6g / 16.05 g/mol = 0.0997 molCalculate the number of electrons in 0.0997 mol of CH4: Each molecule of CH4 contains 10 electrons (4 from carbon and 1 from each of the four hydrogen atoms)Therefore, the number of electrons in 0.0997 mol of CH4 is: Number of electrons = 0.0997 mol × 6.02×10²³ molecules/mol × 10 electrons/molecule Number of electrons = 6.02 ×10²³electronsTherefore, there are approximately 6.02 × 10²³ electrons in 1.6 grams of methane.

Q92. A bottle of cold drink contains 200 ml liquid in which CO2 is 0.1 molar . Suppose carbon dioxide behaves like an ideal gas the volume of dissolved carbon dioxide at STP is?

• A. 0.224 L
• B. 0.448 L✓
• C. 22.4 L
• D. 2.24 L
• E. 25.5

Explanation: This is the following solution:

Q93. Silver oxide decomposes when heated to silver and oxygen. If 0.5 moles of lunar caustic is heated up to 450 degrees, giving out Nitrogen dioxide and oxygen leaving silver as metal, what is the mass of the residue?

• A. 108 grams
• B. 54 grams✓
• C. 216 grams
• D. 27 grams
• E. 92 grams

Explanation: On decomposition silver nitrate gets converted into silver, nitrogen dioxide, and oxygen gas. Following is the balanced chemical equation for the decomposition of silver nitrate: 2 AgNO3 → 2 Ag + 2 NO2 + O2 From balanced chemical equation we get; 2 moles of lunar caustic (AgNO3) give 2 moles of Ag . So, 0.5 moles of lunar caustic will give 0.5 moles of Ag. moles = mass/molar mass mass = moles * molar mass mass = 0.5 * 107.8 mass = 53.9 or 54 g.

Q94. The molecular formula expresses?

• A. Relative number of atoms and electrons
• B. Actual number of atoms✓
• C. Both relative and actual number of atoms
• D. None of the above

Explanation: Molecular formula represents the actual number of atoms in a molecule. Relative numbers of atoms are shown by empirical formula.

Q95. Many elements have fractional atomic masses. This is because:

• A. Mass of atom is itself reactional
• B. Atomic masses are average masses of isobars
• C. Atomic masses are average masses of isotopes
• D. Atomic masses are average masses of isotopes proportional to their abundance✓

Explanation: Atomic masses are typically reported as weighted averages that take into account the abundance of each isotope of an element. Most elements exist as a mixture of isotopes, and these isotopes have different masses. The atomic mass of an element listed on the periodic table is a weighted average of the masses of its naturally occurring isotopes. The weighting is based on the abundance of each isotope in nature. Since isotopes have different masses, the atomic mass is not a whole number, and it may appear as a fractional value.

Q96. Solution contains 85.5 g of sucrose (C12H22O11) in 250 cm3. What is its molarity?

• A. 1 M✓
• B. 0.5 M
• C. 0.25 M
• D. 2 M

Explanation: Molarity is moles of a substance divided by the volume in liters or cubic decimeters. For moles, divide the given mass with the molar mass of sucrose, which is (12x12+22+11x16) 342 grams per mol. Number of moles is 85.5/342 which comes out to 0.25 mol. To convert 250 cubic cm to liters, divide by 1000, so this comes out to 0.25 liters. Molarity = 0.25/0.25 = 1M so, answer is A.

Q97. In which of the following will water evaporate earlier?

• A. Cup
• B. Saucepan✓
• C. Glass
• D. Small bowl

Explanation: The rate of water evaporation depends on various factors such as the surface area exposed to air, temperature, humidity, and airflow. In general, water will evaporate more quickly in conditions where these factors promote evaporation. If we assume that the initial conditions (temperature, humidity, etc.) are the same for all containers, then the primary factor influencing the rate of evaporation would be the surface area exposed to air. Larger surface areas allow for more water molecules to be in contact with the air, promoting faster evaporation. A wide saucepan typically has a larger surface area compared to a cup, glass, or small bowl. Therefore, under similar conditions, water is likely to evaporate earlier from a saucepan than from the other containers.

Q98. Different kinds of atoms of the same element are called isotope having different _but same _ properties.

• A. Physical, atomic
• B. Physical, chemical✓
• C. Chemical, physical
• D. Chemical, atomic

Explanation: Isotopes of an element have the same atomic number and therefore 'similar chemical properties'. Their physical properties may be 'different'.

Q99. The unit used to express the relative atomic mass is called

• A. Gram unit
• B. Avogadro's number
• C. Atomic mass
• D. Atomic mass unit✓

Explanation: One atomic mass unit (1u) is a mass unit equal to exactly one-twelfth (1/12th) the mass of one atom of carbon-12 isotope, which is the scale used to compare atomic masses. So, the unit used to express relative atomic mass is amu. Thus, option D is correct.

Q100. An example of a solution not in equilibrium is:

• A. Chemical pH indicator
• B. Acid/base buffer
• C. Anhydrous solution✓
• D. Hypotonic solution

Explanation: The term anhydrous is often applied to crystalline substances after the removal of crystallization water. So it is very obvious that it is not an example of a solution in equilibrium. So the correct answer is C. All other options are incorrect because they are in equilibrium.

Q101. The internal energy of an ideal gas depends upon its:

• A. Molecular size
• B. Pressure only.
• C. Volume only
• D. Temperature only✓

Explanation: In an ideal gas the inter-molecular collisions are assumed to be absent and the collisions are perfectly elastic. Thus, the gas possesses only translational kinetic energy and hence the internal energy of the ideal gas depends only on temperature.

Q102. A sample of gas weighs 1.25 g, at 28 C occupying a volume of 2.50 x 102 ml and its pressure is 715 torr. What is the molar mass in grams?

• A. 131.1✓
• B. 1.311
• C. 1.212
• D. 122.1

Explanation: Mass of gas = 1.25 g The volume of gas = 2.50 x 102 ml= 0.25 L Pressure of gas = 715 torr The temperature of gas = Using the ideal gas law, PV=nRT PV=(m/M)RT M=mRT/PV where, M = Molar mass of gas W = Mass of gas R = gas constant T = temperature of the gas P = Pressure of gas V = Volume of gas Now put all the given values in the above formula, and we get the value of the molar mass of gas. M=(1.25)(62.364)(1.25)/(715)(0.25) M=131.1g/mol

Q103. Which pair has 1 electron in it’s ‘s’ orbital?

• A. Li & Fe
• B. Na & Cr✓
• C. K & Mn
• D. H & He

Explanation: Na electron configuration is 1s2 2s2 2p6 3s1.Cr electron configuration is [Ar] 3d⁵ 4s¹.

Q104. Which of the following has lowest e/m ratio?

• A. Li+2
• B. H+
• C. He+
• D. Be✓

Explanation: The charge to mass ratio is called the e/m ratio. e/m ratio is a physical quantity, widely used in the electrodynamics of charged particles. All we have to do in this scenario is divide the net charge of the species given in the options by their respective relative atomic mass. As Be is practically neutral, it has no net charge or a charge of zero making its e/m zero as well; the lowest out of the options provided.e/m value of cathode ray particle is (1.758820088±39)×1011 [C/kg]

Q105. According to the general gas equation, density of an ideal gas depends upon:

• A. Pressure
• B. Temperature
• C. Molar Mass
• D. All of these✓

Explanation: According to the ideal gas law Density = pM / RT where p represents Pressure, M is for the Molar mass, R is the Ideal gas constant and T is the Temperature. The equation presented above is derived from the standard equation that is; pV=nRT where n is the number of moles of the gas.

Q106. The actual volume of gas molecules is considered negligible at following pressures:

• A. 1 atm✓
• B. 4 atm
• C. 6 atm
• D. 8 atm

Explanation: The actual volume of the molecules of a gas is usually very small as compared to the volume of the vessel and hence it can be neglected. This volume, however, does not remain negligible when the gas is subjected to high pressure." (Section 3.10.1, gases)

Q107. CO2 and SO2 both are tri-atomic molecules but heat of vaporization of SO2 is greater than that of CO2 due to:

• A. High electronegativity of S
• B. Greater size of SO2
• C. SO2 is polar and CO2 is non-polar✓
• D. SO2 is more acidic than CO2

Explanation: More polar molecules tend to form strong intermolecular forces which require a significant amount of heat to be overcome hence SO2 has a greater latent heat of vaporization. The polarity difference between the two molecules is explained below: CO2 is a linear molecule so the resultant dipole moment is zero as the individual dipole moments of the two CO bonds cancel each other out. SO2, on the other hand, is an angular molecule due to which it has a net dipole moment hence SO2 is polar and CO2 is non-polar.

Q108. Which of the following best describes the emission spectrum of atomic hydrogen?

• A. a discrete series of lines of equal intensity and equally spaced with respect to wavelength equally
• B. a series of only four lines
• C. a continuous emission of radiation of all frequencies
• D. several discrete series of lines with both intensity and spacings between lines decreasing as the wavenumber increases with each series.✓

Explanation: The emission spectrum of atomic hydrogen has been divided into a number of spectral series, with wavelengths given by the Rydberg formula. These observed spectral lines are due to the electron making transitions between two energy levels in an atom. These lines have decreasing spacings(as shown below)

Q109. The Balmer series lies in which region of the electromagnetic spectrum?

• A. Ultraviolet
• B. Visible✓
• C. Infrared
• D. Microwave

Explanation: The Balmer series lies in the visible region of the electromagnetic spectrum.

Q110. How many electrons can have the values n=2, l=1, and s=+½ in the configuration 1s2, 2s2, 2p3?

• A. 1
• B. 3✓
• C. 5
• D. 7
• E. 9

Explanation: 2nd shell has a principal quantum number(n)=2; p-orbital has an azimuthal quantum number(l)=1; spin state=+½ implies electron spinning in the anti-clockwise direction. Anti-clockwise spinning electron in p orbital and in 2nd shell there are 3 of them in the scenario above.

Q111. If uncertainty in the position of an electron is zero the uncertainty in its Momentum is?

• A. 1
• B. Zero
• C. 2 x pi x r
• D. >h/4pi
• E. Infinite✓

Explanation: According to Heisenberg's uncertainty principle, it is impossible to measure position x and momentum p simultaneously.Use ∆x∆p ≥ h/4π as ∆x → 0, ∆p → ∞ Here, neither uncertainty can be zero and if the position is zero the uncertainty in momentum becomes infinite.

Q112. When B- particles are sent through a thin metal foil, most of them go straight through the foil as:

• A. B- particles are much heavier than electrons
• B. B- particles are positively charged
• C. Most part of the atom is empty space✓
• D. B- particles move with high velocity

Explanation: They pass through tin metal foil because most space of the atom is empty, explained by Rutherford in his gold foil experiment.

Q113. Electronic configuration of M2+ ion is 2, 8, 14 and its atomic weight is 56 amu. The number of neutrons in its nucleus are:

• A. 30✓
• B. 32
• C. 42
• D. 52

Explanation: Total number of electrons in M2+ ions are 2+8+14=24, since they lost two electrons to become this ion that means neutral M will have 26 electrons. Since neutral atoms have the same numbers of electrons and protons so the number of protons in M is also 26. As the question states that the mass number of M2+ is 56. Mass number, being the sum of protons and neutrons, can be used to calculate neutrons, by subtracting protons from it(56-26=30)

Q114. Oxidation number of Nitrogen in HNO3, is:

• A. +4
• B. +2
• C. +6
• D. +5✓
• E. +7

Explanation: Oxide ion has a charge of -2. Three oxide ion will thus have a charge of -6H has a charge of +1.N is HNO3 will thus be:-6+1+x=0x=+5.

Q115. The oxidation number of all the elements in the free state is:

• A. 1
• B. 3
• C. 0✓
• D. -1
• E. -3

Explanation: All the elements have an oxidation number of 0 in the free state.

Q116. The reaction: Cl2 + H2O→ HCl + HOCl is an example of:

• A. Oxidation reaction
• B. Reduction reaction
• C. Auto-oxidation and reduction reaction✓
• D. Substitution reaction
• E. Addition reaction

Explanation: Auto-oxidation and reduction reaction is a reaction in which the same element is oxidized as well as reduced. In the reaction given above, the Cl element reduces to Cl-(HCl) and oxidizes to Cl+(in HOCl).

Q117. In the following reaction: 3Br2 +6CO32- + 3H2O → 5Br-1 + BrO3-1 + 6HCO3-1

• A. bromine is reduced and water Is oxidized
• B. bromine is both reduced and oxidized✓
• C. bromine is oxidized and carbonate is reduced
• D. bromine is neither reduced or oxidized

Explanation: The oxidation state of bromine in Br2 is 0. It is reduced to bromide ion where its oxidation number is -1 and it is oxidized to BrO3-1 where the oxidation state of bromine is +5. Oxidation states of hydrogen, carbon, and oxygen remain the same. So, the option is correct.

Q118. If we balanced the following reaction , what is the net ionic charge on the right side of the equation? _H+ +_ MnO4- + _ Fe2+ →_ Mn2+ + _ Fe3+ + _ H2O

• A. +5
• B. +7
• C. +10
• D. +17✓

Explanation: Correct option is '+17'. This will be balanced using the ion-electron method. Calculte the net charge on the RHS of the equation which should be the same for the LHS. The net ionic charge on either side must be zero for the equation to be balanced.

Q119. The quantum numbers +½ and -½ for the electron spin represent:

• A. Rotation of the electron in clockwise and anticlockwise direction respectively
• B. Rotation of the electron in anticlockwise and clockwise direction respectively
• C. Magnetic movement of the electron pointing up and down respectively
• D. Two quantum mechanical spin states which have no classical analogue✓

Explanation: There are two quantum mechanical spin states which are represented by the positive and negative halves,which don’t possess any specific position.

Q120. Which one of the following is not an isotope of hydrogen:

• A. Deuterium
• B. Tritium
• C. Ortho hydrogen✓
• D. None of these

Explanation: Ortho-para hydrogen are spin isomers of hydrogen . Hydrogen only has 3 isotopes. Refer to the image below:

Q121. For a chemical reaction A + B, the threshold energy of the reaction is 31 KJ/mole. The average internal energy of A is 12 KJ/mole. What will be the activation energy of A?

• A. 43 KJ/mole
• B. 37 KJ/mole
• C. 25 KJ/mole
• D. 19 KJ/mole✓

Explanation: Threshold E = activation E + normal E of reactant 31 = A + 12 A = 31 - 12 = 19 kJ/mol

Q122. ΔH = ΔE + PΔV is the change in enthalpy at constant _.

• A. Volume
• B. Pressure✓
• C. Temperature
• D. Mass

Explanation: The answer is B which is pressure mainly because in the equation Pressure has no delta sign on it indicating that the change in pressure is not required hence, we need a constant pressure while applying this equation.

Q123. Which one of the following equations correctly defines the enthalpy changes of formation of carbon monoxide:

• A. C(s) + 1/2 O2 -> CO(g)✓
• B. C(g) + 1/2 O2 -> CO(g)
• C. C(s) + O(g) -> CO(g)
• D. C(g) + CO2 (g) -> 2CO(g)

Explanation: Since we are talking about the enthalpy of formation, we must ensure that the product has only one mole and the reactants are in their elemental forms. The answer is A since carbon naturally exists as a solid whereas Oxygen gas exists as diatomic molecules. Moreover, stoichiometry must also be considered in which equal moles of carbon and oxygen are present on both, the product and the reactant side.

Q124. Two rocket fuels below are determined by their high performance. N2H4(l) + O2(g) -> N2(g) + 2H2O(l) ΔH= -632 kJ H2 (g) + ½ O2(g) -> H2O(l) ΔH = -286 kJ If equal masses of hydrazine and hydrogen are used, which of the following has better performance?

• A. Hydrazine
• B. Both have equal enthalpy of formation
• C. Hydrogen gas✓
• D. Cannot be compared

Explanation: The performance of rocket fuel is measured by its enthalpy of combustion, which is the amount of heat released when one mole of the fuel is completely burned in excess oxygen to form its products at standard conditions. The enthalpy of the formation of hydrazine is -632 kJ/mol, and that of hydrogen gas is -286 kJ/mol. Since equal masses of hydrazine and hydrogen are used, we can compare their performances by calculating the amount of heat released per gram of fuel. >For hydrazine, the amount of heat released per gram of fuel is (-632 kJ/mol) / (32 g/mol) = -19.75 kJ/g. >For hydrogen gas, the amount of heat released per gram of fuel is (-286 kJ/mol) / (2 g/mol) = -143 kJ/g. Therefore, hydrogen gas has better performance as a rocket fuel than hydrazine since it releases more heat per gram of fuel.

Q125. Given the bond energy N ≡ N, N - H and H - H bonds are 945, 391, and 436 kJmol-1 respectively, the enthalpy of the reaction N2(g) + 3H2(g) -> 2NH3(g) is;

• A. -93 kJ✓
• B. 102 kJ
• C. 90 kJ
• D. 105 kJ.

Explanation: It takes 945 kJ of energy to break N≡N.

Q126. The enthalpy change of the reaction H2(g) + ½ O2 -> H2O (l) under standard conditions is:

• A. Enthalpy change of formation of water.
• B. Enthalpy change of neutralization.
• C. Both; enthalpy change of combustion of hydrogen and enthalpy change of formation of water.✓
• D. Enthalpy change of combustion of hydrogen.

Explanation: Since 1 mole of H2 is being combusted, it can be called enthalpy change of combustion of H2. Also, 1 mole of water is being formed from its constituent elements under standard state so it can also be called standard enthalpy change of formation of water.

Q127. The net heat change in a chemical reaction is the same whether it is brought about in two or more different ways in one or several steps. This is known as:

• A. Henry's law
• B. Hess's law.✓
• C. Joule's principle
• D. Dalton's law

Explanation: Hess's Law of Constant Heat Summation (or just Hess's Law) states that regardless of the multiple stages or steps of a reaction, the total enthalpy change for the reaction is the sum of all changes.

Q128. One Calorie is equivalent to:

• A. 0.4184J
• B. 41.84 J
• C. 4.184 J✓
• D. 418.4 J

Explanation: There are 4.184 joules in 1 calorie.

Q129. Which of the following hybrid orbitals has maximum “s” character?

• A. Sp3 hybrid orbital
• B. Sp2 hybrid orbital
• C. Sp hybrid orbital✓
• D. Dsp2 hybrid orbital

Explanation: Presented below is the explanation:Expressions shown in the options e.g. sp2 basically mean that an s orbital is merged with 2 p orbitals. The number in the subscript of p represents the number of p orbitals involved in the hybridization. The greater this number is, the less would be the characteristics of the s orbital apparent in the hybrid orbitals.

Q130. The first ionization energy is maximum for:

• A. Na
• B. Mg✓
• C. Al
• D. K

Explanation: Explanation: Moving from left to right in a period increases the ionization energy. However, the ionization energy of Mg is greater than the ionization energy of Al because the valence shell electron in Al is present in p-orbital while the valence shell electron in Mg is present in s-orbital. Hence the ionization energy of Mg is highest in the options above.

Q131. For the equilibrium reaction 2 NO2 <-> N2O4 (g) (-61 kJ), increase of temperature would:

• A. Favour the Formation of N2O4
• B. Favour the Decomposition of N2O4✓
• C. No Effect on Equilibrium
• D. Stop the Reaction

Explanation: If an exothermic reaction in equilibrium experiences a rise in temperature, the reaction shifts to the left toward reactants. An increase in temperature will favour the reverse reaction. So, N2O4 will undergo decomposition.

Q132. The value K for H2(g) + CO2(g) <-> H2O(g) + CO(g) is 1.80 at 1000 C. If 1.0 mole of each H2 and CO2 are placed in 1 litre flask, the final equilibrium concentration of CO at 1000 C will be:

• A. 0.295 M
• B. 0.385 M
• C. 0.531 M
• D. 0.573 M✓

Explanation: The given reaction is :- H2(g)+CO2(g)⇌H2O(g)+CO(g) Initial moles : 1 1 0 0 At eqm : 1−x 1−x x x Now, KC=[H2O][CO]/[H2][CO2] 1.8=x.x/(1-x)(1-x) ⇒x2=1.8(1−x)2 Taking square root on both sides ⇒x=1.34(1−x)⇒2.34x=1.34 ⇒x=0.573 So, concentration of CO at eqb=0.573M

Q133. Law of mass action was derived by:

• A. Newton
• B. CM Guldberg
• C. P Waage
• D. CM Guldberg and P Waage✓

Explanation: This law was formulated over the period 1864–79 by the Norwegian scientists Cato M. Guldberg and Peter Waage.

Q134. Thermochemistry is very important to learn about

• A. Chemical Equilibrium
• B. Chemical Bonding
• C. Heat contents of a compound✓
• D. All of these

Explanation: Thermochemistry is the study of heat energy which is associated with chemical reactions and/or phase changes such as melting and boiling. A reaction may release or absorb energy, and a phase change may do the same.

Q135. Work done on the system is

• A. Negative
• B. depends upon Boundary Conditions
• C. Positive✓
• D. Zero

Explanation: Work done on the system is positive in chemistry and negative in physics. Similarly work done by the system is negative in chemistry and positive in physics.

Q136. If pressure and volume of a gas are variable while temperature remains constant, this belongs to

• A. Charles's law
• B. Boyle's law✓
• C. Avogadro's law
• D. Pascal's law

Explanation: Boyle's law is a gas law, stating that the pressure and volume of a gas have an inverse relationship. If volume increases, then pressure decreases and vice versa, when the temperature is held constant.

Q137. If a graph is plotted between pressure on x- axis and volume on y- axis for Boyle's law verification, the curve obtained is called

• A. pseudotherm
• B. isotherm✓
• C. biotherm
• D. all of these

Explanation: If a graph is outlined in between pressure on the x-axis (abscissa) and volume on the y-axis (ordinate), then a curve is obtained. This curve is called isotherm 'iso' implies the same, “therm” implies heat.

Q138. Exothermic Reactions heat is

• A. Taken in
• B. Give out to surroundings✓
• C. Neither given nor lost
• D. None of these

Explanation: An exothermic reaction is a chemical or physical reaction that releases heat. It gives out energy to its surroundings. The energy needed for the reaction to occur is less than the total energy released.

Q139. Colour of the transition metal ions/compounds is due to the electrons present in:

• A. d-orbital✓
• B. s-orbital
• C. p-orbital
• D. None of the above

Explanation: Explanation: The color of the transition metal ions/compounds is due to the electrons present in d-orbital. The s-orbitals are typically filled with electrons in the ground state of an atom, and they are not involved in the color of transition metal ions/compounds. The p-orbitals are also typically filled with electrons in the ground state of an atom, and they are not directly involved in the color of transition metal ions/compounds.

Q140. The following question belongs to the topic of motion:

• A. Average velocity
• B. Uniform velocity
• C. Instantaneous velocity✓
• D. Variable velocity
• E. None of the above

Explanation: When the change in time is brought to zero this makes the velocity maximum. Which is also called instantaneous velocity.

Q141. A ball is thrown vertically upward with the velocity of 98 m/sec, how high does the ball rise?

• A. 196 m
• B. 2 m
• C. 1/2 m
• D. 490 m✓
• E. 98 m

Explanation: s=u(t) + (at2)/2s= 98(t) - 4.9t20 = 98 - 9.81(t)t= 10 ss= 980 -490 = 490m This is the maximum height .

Q142. Two blocks, X and Y, of masses m and 2m respectively are accelerated along a smooth horizontal surface by a force F applied to block X, as shown in the diagram. What is the magnitude of the force exerted by block Y on block X during this acceleration?

• A. 0
• B. F/3
• C. F/2
• D. 2F/3✓
• E. F

Explanation: Both blocks will be accelerated when block X is applied by a force of magnitude F. Since, the total mass will be m+2m which is 3m. So, the acceleration of the system will be given as F=ma or a=F/3m. So , from this we can find the force acting on block Y. So, to calculate the force on block Y we have that F(y) =2m*a or 2m*F/3m which on solving we will get the force on the block y as F(y)= 2F/3The magnitude of the force exerted by block Y on block X during this acceleration is = 2F/3

Q143. A box of mass m = 6 kg slides with speed v = 4 m/s across a frictionless floor. It explodes into two pieces: one piece, with mass m1 = 2 kg move in the same direction with speed v1 = 8 m/s. Find the velocity of the second piece.

• A. 2 m/s✓
• B. 4 m/s
• C. 8 m/s
• D. 9 m/s
• E. 11 m/s

Explanation: Before explosion m1 = 6 kg , u1 = 4m/s After the explosion, it explodes into two pieces, such that m1 = 2kg, v1 = 8m/s, m2 = 4 kg, v2 =? In case of an explosion, momentum will remain conserved. According to the Law of Conservation of Momentum: Momentum before explosion =Momentum after the explosion m1u1 = m1v1 + m2v2 (6)(4) = (2)(8)+(4)(v2) 24 = 16 + 4v2 8 = 4v2 v2 = 2 m/s

Q144. A ball of mass 2 kg travelling at 8 ms-1 strikes a ball of mass 4 kg travelling at 2 ms-1 . Both balls are moving along the same straight line as shown. After collision, both balls move at the same velocity v. What is the magnitude of the velocity v?

• A. 4 ms-1✓
• B. 5 ms-1
• C. 6 ms-1
• D. 8 ms-1
• E. 10 ms-1

Explanation: According to the Law of Conservation of Momentum: Momentum before collision=Momentum after collision (8)(2)+(4)(2)=(6)(v) 16+8=6v 24=6v v=4ms-1

Q145. At what angle of projection of a projectile the range becomes half of its maximum value?

• A. 15✓
• B. 20
• C. 30
• D. 40

Explanation: R=Vi2(sin 2θ)/gAt given condition:Maximum range= Rmax= vi2θ/g. For the maximum range, sin2θ=1 which is possible if we put the angle as 45 degrees but to get half of the maximum range we should take θ such that sin2θ is equal to 0.5. It is known that sin 30=0.5 so if we put θ as 15 we will get sin2(15)=sin 30=0.5.

Q146. An apple is thrown with a speed of 30 m/s in a direction 30° above the horizon. Find out its horizontal range. (g= 9.8 m/s2)

• A. 20 m
• B. 40 m
• C. 60 m
• D. 80 m✓
• E. 100 m

Explanation: Given: V(i)= 30m/sTheeta=30°Find: Horizontal Range=? Time=?Solution:Formula: R=V(i)t V(i) =V(i)x= V(i) sin(theeta) Using equations of motion:V(f)=V(i) + at0=30sin(30)+ 10(t)15=10t15/10=t=1.5tTotal time= 1.5×2=3m/sHorizontal speed.V(i)=30cos(30)=15Horizontal range: R=V(i)tR=30cos(30) ×3=76.5m~80

Q147. A particle is projected from the ground with a kinetic energy E at an angle of 60 degree with the horizontal. Its kinetic energy at the highest point of its motion will be:

• A. E
• B. E/2
• C. E/4✓
• D. E/8

Explanation: At the highest point, the vertical component of velocity will be zero. The horizontal component Vx is given by , Vx= V cosθVx = V cos 60= V/2The kinetic energy will be given by:K.E = ½ mv2K.E’ = ½ m(V/2)2K.E’ = ½ m(v2/4)K.E’ = ¼(K.E)

Q148. A man throws a ball vertically upward in the compartment of an accelerated train. The ball will fall:

• A. ln front of him
• B. In his hand
• C. Behind him✓
• D. Beside him

Explanation: At the time of throwing the ball, it inherits velocity of platform at that moment . And, the horizontal velocity of the ball is constant in the air, because no acceleration in horizontal direction for ball. However, the train is accelerating in forward direction then from frame of train, the ball has horizontal component of acceleration in backward direction.

Q149. A bomber drops a bomb when it is vertically above the target. It misses the target because of the:

• A. Vertical component of the velocity of bomber
• B. Force of gravity
• C. Acceleration of the bomber
• D. Horizontal component of the velocity of bomber✓

Explanation: When a bomber drops a bomb, the bomb will follow a projectile trajectory influenced by both the vertical and horizontal components of the bomber's velocity. The force of gravity acts vertically downward and affects the vertical motion of the bomb, causing it to fall towards the ground. However, the horizontal component of the bomber's velocity determines the horizontal distance the bomb will travel before hitting the ground. If the bomber's horizontal velocity is not aligned with the target, the bomb will miss the target horizontally.

Q150. A neutron travels a distance of 24 m in a time interval of 3.6 x 10^-4 s. Assuming its speed was constant. Find its kinetic energy. Take 1.7 x 10^-27 kg as the mass of the neutron.

• A. 37.702 x 10^-19 joule✓
• B. 27.702 x 10^-19 joule
• C. 17.70 x 10^-19 joule
• D. 07.702 x 10^-29 joule

Explanation: speed of neutron = distance travelled by neutron / time taken by neutron for covered that distance . speed of neutron = 24/3.6 × 10-4 m/s speed of neutron ( V)= 6.6 × 10⁴ m/s now , kinetic energy = 1/2mv² K.E = 1/2 × 1.7 × 10-27 ×( 6.6 × 10⁴)² J = 1/2 × 1.7 × (6.6)² × 10-19 j =37.2 × 10-19 j so, K.E = 37.2 × 10-19. Hence the correct answer is A which is closest to the correct answer

Q151. A 60 kg boy runs up a hill through a height of 6 m in 3 seconds. How much work does he do against gravitational force?

• A. 3000 J
• B. 2528 J
• C. 3500 J
• D. 3528 J✓

Explanation: W=mgh=(60)(6)(9.8)=3528J

Q152. The nature of the force of gravitation in the universe is:

• A. Repulsive only
• B. Attractive only✓
• C. Electric
• D. Magnetic
• E. Both attractive and repulsive

Explanation: Both in the Newton theory of gravitation and in the General Theory of Relativity the gravitational force is an exclusively attractive one.

Q153. The third law of motion given by Newton deals with an action- reaction pair of forces. Consider two bodies: if the action is due to one body, the reaction will be due to:

• A. The other body✓
• B. The same body
• C. Both the bodies
• D. Atmosphere

Explanation: Newton's third law: If an object A exerts a force on object B, then object B must exert a force of equal magnitude and opposite direction back on object A

Q154. Beta particles are the particles emitted from the _ of an atom.

• A. Inner atomic shells
• B. Outer atomic shells
• C. Innermost atomic shell
• D. Nucleus✓

Explanation: The beta particle, which may be either negatively charged (negatrons) or positively charged (positrons), originates from the nucleus of an atom. A beta particle is emitted from the nucleus of an atom during radioactive decay. The electron, however, occupies regions outside the nucleus of an atom.

Q155. A ball is thrown vertically upward with a velocity of 98 m/s. How long does it take to reach its highest point?

• A. 2 seconds
• B. 5 seconds
• C. 7 seconds
• D. 10 seconds✓
• E. 15 seconds

Explanation: Given :u = 98 m/sg = -9.8 m/s². ( As it is thrown upwards)v = 0 (As it will stop after reaching highest point)Using2gs = v² - u²2 × -9.8 × s = - (98 × 98)s = (98 × 98)/(2 × 9.8)s = 98 × 5s = 490 m.Now, Usingv = u + at0 = 98 - 9.8 × tt = 10 s

Q156. A rotating wheel of radius 0.5 m has an angular velocity of 5 rad/s at some instant and 10 rad / s after 5 s. Find the angular acceleration of a point on its rim.

• A. 1 rad / s2✓
• B. 3 rad / s2
• C. 5 rad / s2
• D. 7 rad / s2
• E. 9 rad / s2

Explanation: Explanation is given below

Q157. When the aircraft Concorde is moving in a horizontal plane at a constant speed of 650 ms-1, its turning circle has a radius of 80 km. What is the ratio of the centripetal force to the weight of the aircraft? (g = 9.8 m/s2)

• A. 8.3 x 10^4
• B. 0.54✓
• C. 1.9
• D. 52
• E. 540

Explanation: The ratio of Centripetal force to the weight of the aircraft=mv^2/r divided by mgm*(650)^2/80*1000 / m*9.81=0.54.

Q158. A football, at rest on the ground, is kicked with an initial velocity of 10 m/s at a launch angle of 30°. Calculate its total flight time, assuming that air resistance is negligible.

• A. 0.5 s
• B. 1 s✓
• C. 1.7 s
• D. 2 s
• E. 4 s

Explanation: T=2u sinθ/g T=2x10xsin(30)/10 T=2x1/2 T=1s.

Q159. A student is performing a lab experiment on simple harmonic motion. He has two different springs (with force constants k1 and k2) and two different blocks (of masses m1 and m2). If k1 =2k2, and m1 = 2m2 , which of the following combinations would give the student the spring-block simple harmonic oscillator with the shortest period?

• A. The spring with force constant k1 and the block of mass m1
• B. The spring with force constant k1 and the block of mass m2✓
• C. The spring with force constant k2 and the block of mass m1
• D. The spring with force constant k2 and the block of mass m2
• E. All the combinations above would give the same period

Explanation: The period of the spring-block simple harmonic oscillator is given by the equation T =2π√m/k so, to make T as small as possible, we want m to be as small as possible and k to be as large as possible. Since m2 is the smaller mass and k1 is the larger spring constant, this combination will give the oscillator the shortest period.

Q160. A 400 gram ball is tied to the end of a cord and whirled in à horizontal circle of radius 0.6 m. If the ball makes five complete revolutions in 2 s, what is the ball's linear speed?

• A. 4.42 m/s
• B. 5.42 m/s
• C. 7.42 m/s
• D. 8.42 m/s
• E. 9.42 m/s✓

Explanation: Linear speed = Distance / TimeDistance = 5 × 2 × pi × r = 5 × 2 × 22/7 × 0.6 = 132 / 7 = 18.85 mspeed = 18.85 / 2 = 9.42 m/s

Q161. A body of mass 4 kg attached to a spring is displaced through 0.04 m from its equilibrium position and then released. If the spring constant is 400 N/m, find the time period of the vibration?

• A. 4.567
• B. 3.416
• C. 2.315
• D. 1.325
• E. 0.628✓

Explanation: This is the solution to this question: The time period of vibration can be calculated using the formula: T = 2π * √(m/k) where T is the time period, m is the mass of the body and kis the spring constant. In this case, the mass of the body is 4 kg, and the springconstant is 400 N/m. T = 2π * √(4 kg / 400 N/m) T = 2π * √(0.01 s^2/kg) T = 2π * 0.1 s T ≈ 0.628 s Therefore, the time period of vibration for the bodyattached to the spring is approximately 0.628 seconds.

Q162. A car going around a certain curve at a speed of 25 km/h has a centripetal force acting on it of 100 N. If the speed of the car is doubled, the centripetal force:

• A. Is quadrupled✓
• B. Is doubled
• C. Is multiplied by the √2
• D. Is reduced to ½ of the original value
• E. Is reduced to ⅙ of the original value

Explanation: a=v^2/r Where a is centripetal acceleration and v is linear velocity and r is the radius. When velocity is doubled the centripetal acceleration will be quadrupled.

Q163. A stone is thrown horizontally from 2.4 m above the ground at 35 m/s. The wall is 14 m away and 1 m high. At what height will the stone reach when at the wall? Where will the stone land?

• A. 1.62 m , 24.5 m✓
• B. 2.22 m , 31 m
• C. 3.22 m , 41 m
• D. 4.22 m , 51 m
• E. 5.22 m , 61 m

Explanation: A stone is thrown horizontally from 2.4m above the ground with a speed of 35 m/s. time is taken to reach a point which is located 14m away from the stone, t = 14/35 = 0.4s vertical displacement covered by a stone during 0.4 sec, here, so, y = 0 - 1/2 × g × (0.4)² if g = 10 m/s² then, y = -1/2 × 10 × 0.16 = -0.8m so, position of stone from the ground = 2.4m - 0.8m = 1.6 m but it is given that the height of the wall is just 1m. so, the stone doesn't hit the wall and the stone is 1.6m above the ground, where the wall stands. now again applying the formula, where, y = -2.4 m , or, -2.4 m = 0 - 1/2 × 10 × t² or, t² = 0.48 ⇒t = 0.7sec so, x = ut = 35m/s × 0.7s = 24.5 m Hence, the stone hits the ground 24.5 m away from the initial position of it.

Q164. If during circular motion, tangential velocity of a body becomes double, then centripetal force becomes:

• A. Double
• B. One half
• C. Four times✓
• D. One fourth

Explanation: Fc= mv^2/ r F is directly proportional to the square of the linear velocity. If velocity doubles then Fc will quadruple.

Q165. A train is approaching a station at 90 km/h sounding a whistle of frequency 1000 Hz. What will be the apparent frequency heard by the listener sitting on the platform if the train moves away from the station at the same speed? (speed of sound= 340 m/s)

• A. 931.5 Hz✓
• B. 105.7 Hz
• C. 135.9 Hz
• D. 153.1 Hz
• E. 164.9 Hz

Explanation: This is the solution to this question:

Q166. A simple pendulum completes one oscillation in 4 seconds. Calculate its length when g= 9.8 m/s2, as the time period of a simple pendulum is given by T = 2 π √(l/g)

• A. 3.973 m✓
• B. 5.123 m
• C. 7.111 m
• D. 9.231 m
• E. 12.141 m

Explanation: Given: T=4sg=9.8 m/s2Formula: T=2π√l/g Solution:4=2×3.142×√l/√10(4×√10)2/(2×3.124)2= (√l)2l= approximately 4.

Q167. A body is executing simple harmonic motion if:

• A. Its acceleration is directly proportional to displacement and directed towards mean position✓
• B. Its acceleration is inversely proportional to displacement and directed away from mean position
• C. Its acceleration is inversely proportional to displacement and directed towards mean position
• D. Its acceleration is directly proportional to displacement and directed away from mean position

Explanation: A body executes SHM if the acceleration produced is directly proportional to the displacement and directed toward the mean position. So option A is correct. All other options are incorrect because they do not satisfy the necessary conditions for simple harmonic motion.

Q168. The time of open vibration of a simple pendulum may be decreased by:

• A. Increasing the length of the pendulum
• B. Decreasing the length of the pendulum✓
• C. Using a heavier bob
• D. Using a lighter bob

Explanation: The 'time of one vibration' of the simple pendulum can be decreased by decreasing the pendulum length. The period of simple pendulum is given by;T=,So there is direction relation between time period and length of pendulum. Therefore in order to decrease the time period the length of pendulum is decreased.Time period has nothing to concern with mass so option C & D are not related to the given question.

Q169. An aeroplane is flying in a straight line at a constant altitude. If a wing gust strikes and raises the nose of the airplane, the nose will bob up and down until the plane eventually returns to its original position. These oscillations are:

• A. Undamped
• B. Underdamped
• C. Critically damped✓
• D. Overdamped

Explanation: This is an example of a damped oscillation. A damped oscillation means an oscillation that fades away with time. Examples include a swinging pendulum, a weight on a spring, and also a resistor.

Q170. The direction of the magnetic line of force depends upon:

• A. Nature of the material of the conducting wire
• B. Area of the conducting wire
• C. Amount of the current
• D. Direction of the current✓

Explanation: The direction of the magnetic force depends on the direction of the current and the direction of the magnetic field. Of these two, the direction of the current is in options so that will be the correct answer.

Q171. Weber x ampere per meter is equal to:

• A. Joule
• B. Watt
• C. Newton✓
• D. Henry

Explanation: Wb amp\ metre =? wb=BxA Wb=Nm\A Wb amp\ metre= [Nm\A] xA\m Wb amp\ metre =NmxA\Axm BY CANCELLATION OF THE COMMON VALUES WE GET NEWTON [N] VIDEO EXPLANATION;

Q172. The values of electric intensity will _ due to the presence of dielectric medium:

• A. Increase
• B. Increase exponentially✓
• C. Decrease
• D. Remain same

Explanation: The strength of the electric field is reduced due to the presence of dielectric. If the total charge on the plates is kept constant, then the potential difference is reduced across the capacitor plates.

Q173. In what form is the energy stored in a charged capacitor?

• A. gravitational
• B. electrical potential✓
• C. magnetic field
• D. potential

Explanation: Energy is stored in a form of electrostatic field between plates of capacitor. This energy can be expressed in the form of work done by the battery.

Q174. Ohm multiplied by farad is equivalent to:

• A. Time✓
• B. Charge
• C. Distance
• D. Capacitor

Explanation: The formula for charging and discharging capacitor is RC=T R: resistance C: capacitance T: time for charging/ discharging

Q175. “The magnitude of electrostatic acceleration force between two point charges is directly proportional to the product of the magnitude of the charges and inversely proportional to the square of the distance between them.” This is known as:

• A. Gauss’s Law
• B. Ohm’s law
• C. Faraday's law
• D. Newton's Law
• E. Coulomb's Law✓

Explanation: Coulomb’s law states that magnitude of electrostatic acceleration force is directly proportional to the product of the magnitude of two charges and inversely proportional to the square of the distance between them.

Q176. The net charge flowing through any section of the conductor per unit time is known as?

• A. Electric intensity
• B. electric flux
• C. electric current✓
• D. electric potential
• E. dielectric constant

Explanation: Net charge flow through conductor in unit time is known as current. Current is measured in ampere.

Q177. If the potential difference of 1 volt is applied across the end of a conductor and the current flowing through the conductor is one ampere then the resistance of the conductor is said to be?

• A. 1 Farad
• B. 10 Coulomb
• C. 1 Ohm✓
• D. 1 coulomb
• E. 10 Ohm

Explanation: Potential difference=V=1 volt Current=I=1 Ampere According to Ohm's Law: V=IR Resistance R = Voltage V/ Current I R=1 volt / 1 Ampere R=1 ohm , so option C is correct. As this question is theoretical, options A, B,D and E are all incorrect

Q178. _ is defined as the sensation that sound produces in the ear of a listener and is clearly related to the frequency of sound. Frequency and _ are both measured in Hertz (Hz). Thus greater the frequency the greater the _ and lower the frequency lower the _.

• A. Quality ... Pitch ... Loudness ... Pitch
• B. Pitch ... Pitch ... Pitch ... Pitch✓
• C. Loudness ... Quality ... Pitch ... Quality
• D. Quality ... Quality ... Quality ... Quality
• E. Loudness ... Loudness ... Loudness ... Loudness

Explanation: The quality of a sound governed by the rate of vibrations producing it; the degree of highness or lowness of a tone is generally called pitch. Pitch is defined as the sensation of sound in the ear related to frequency. Pitches are measured by using a tool called hertz. Hertz measures one second of sound pitches and creates a calculated visual of the sound wave. Pitch is related to the frequency as pitch increases when the frequency is increased and decreases with the decrease in frequency.

Q179. If two sounds have the same wavelength in air at the same temperature, what other property must they also have in common? Intensity Amplitude Frequency

• A. I only
• B. III only✓
• C. I and II only
• D. II and III only
• E. I, II and III

Explanation: For wavelength to be constant for waves, their frequency and velocity should be the same as suggested by the formula velocity = frequency x wavelength. That is why the answer is III (frequency only)

Q180. A progressive wave moving along the X axis is represented by y = A sin [(2 π(vt-x) / λ )]. The wavelength at which the maximum particle velocity is 3 times the wave velocity is:

• A. A/3
• B. 3π
• C. 3 / 4 λ A
• D. 2 / 3 ( πA)✓

Explanation: This is the solution to this question:

Q181. The beat frequency is given by:

• A. |fa - fb|✓
• B. |fa ÷ fb|
• C. |fa x fb|
• D. |fa + fb|

Explanation: Beat is produced when two waves of nearby frequencies superimpose when they travel in the same path. This causes a periodic variation of intensity of the resultant wave.The beat frequency is the number of beats produced per second.The formula for beat frequency is the difference in frequency of the two superimposed waves.

Q182. If modulated signal frequency is represented by fm, carrier frequency by fc, fmin and fmax represent minimum and maximum values respectively, then the lower sideband refers to the range:

• A. fc - fmax to fc - fmin✓
• B. fc + fmin to fc + fmax
• C. fc - fm
• D. fm - fc

Explanation: Lower sidebands (LSB) range from fc-fmax to fc-fmin.

Q183. How many types of modulations are possible with sinusoidal carrier?

• A. Only one
• B. Two
• C. Three✓
• D. Four

Explanation: The carrier signal is a sine wave at the carrier frequency. The sine wave has three characteristics that can be altered. The term that may be varied is the carrier voltage Ec, the carrier frequency FC, and the carrier phase angle θ. So three forms of modulations are possible.

Q184. The frequency of a man's voice is 300 Hz. If velocity of sound is 336 m/s, the wavelength of the sound is:

• A. 1.12 m✓
• B. 300 m
• C. 330 m
• D. 112 m
• E. 11201 m

Explanation: We are given thatfrequency=300Hz, and velocity v=336ms−1From the relation v=f×λ,λ=v/f=336/300=1.12mOption "A" is correct.

Q185. If the temperature is increased from 200K to 800K, then what would be the change in pressure at constant volume?

• A. Increases by factor 4✓
• B. Decreases by factor 4
• C. Increases by factor 2
• D. Decreases by factor 2

Explanation: PV=NR DELT V=constant ;R=constant;N=constant so P is directly proportional toT as the temperature increases 4 times as it increases from 200K to 800K so the pressure will also increase 4 times.Just be careful that the units (especially temperature) are absolute.

Q186. If electron passes through axis of solenoid the movement will be:

• A. Towards the outward
• B. Towards the inward
• C. Parallel to its motion
• D. No force acts on it✓

Explanation: The electron is moving along the axis with velocity V Force = q(V x B) Velocity and magnetic field are in the same direction or at an angle of 180 V x B = VBsin(0 or 180) = 0 Force = 0 The image shows the direction of the magnetic field inside a solenoid.

Q187. The current measuring part of the Ammeter consists of a number of low resistors connected ...

• A. At an angle of 180 degrees with the galvanometer
• B. Parallel with galvanometer✓
• C. At an angle of 45 degrees With the galvanometer
• D. Perpendicular with the galvanometer

Explanation: Since Galvanometer is a very sensitive instrument therefore it can't measure heavy currents. In order to convert a Galvanometer into an Ammeter, a very low resistance known as "shunt" resistance is connected in parallel to the Galvanometer.

Q188. The value of universal constant "R" is:

• A. 8.314 J mol-31K-3
• B. 1.38J mole-1 K-3
• C. 1.38J mole-1 K-1
• D. 8.314 J mole-1 K-1✓

Explanation: Physically, the gas constant is the constant of proportionality that relates the energy scale in physics to the temperature scale, when a mole of particles at the stated temperature is being considered. The value of R is 8.314J⋅K−1⋅mol−1

Q189. For adiabatic process, the first law of thermodynamics is:

• A. w = ∆u = Q
• B. Q = -w
• C. Q = w
• D. w = -∆u✓

Explanation: An adiabatic process is one in which no heat is gained or lost by the system. The first law of thermodynamics with Q=0 shows that all the change in internal energy is in the form of work done. This condition can be used to derive the expression for the work done during an adiabatic process.When a gas expands, it does work on the surroundings; compression of a gas to a smaller volume similarly requires that the surroundings perform work on the gas. If the gas is thermally isolated from the surroundings, then the process is said to occur adiabatically.The first law is;ΔQ=ΔU+w In an adiabatic change, q = 0, so the First Law becomes 0=ΔU+w. -ΔU=w. or ΔU=-w. Since the temperature of the gas changes with its internal energy, it follows that adiabatic compression of a gas will cause it to warm up, while adiabatic expansion will result in cooling. VIDEO EXPLANATIONS;

Q190. A battery has an e.m.f of 6.0 volts and an internal resistance of 0.4 ohms. It is connected to a 2.6 ohms resistor through a SPST (single pole, single throw switch). When the switch is open, the potential difference between the terminal of the battery is:

• A. 0 V
• B. 0.8 V
• C. 2.6 V
• D. 5.2 V
• E. 6.0 V✓

Explanation: The emf of a battery is generated by the chemical action in the battery. When no current is being drawn from the battery, the difference in potential between the terminals is equal to the emf.

Q191. A battery has an e.m.f. of 4 V and internal resistance 'r'. When this battery is connected to a resistance of 2 ohms, a current of 1 amp flows in the circuit. How much current will flow if the terminals of the battery are connected directly:-

• A. 1 A
• B. 2 A✓
• C. 4 A
• D. 6 A
• E. infinite

Explanation: Current in the circuit is I = E/r + R = 4/r + 2 = 1 or 2 + r = 4 or r = 2 ohms When the terminals of battery are connected directly, the current = E/r = 4/2 = 2A

Q192. A battery has an e.m.f of 6.0 volts and an internal resistance of 0.4 ohm. It is connected to a 2.6 ohm resistor through a SPST (single pole, single throw switch): When the switch is closed, the potential difference between the terminal Is, in volts is:

• A. 0
• B. 0.8
• C. 2.6
• D. 5.2✓
• E. 6.0

Explanation: Total current = V/R= 6/3= 2V = IR2.6 x 2 = 5.2

Q193. The information received at the other end of a fibre can be inaccurate due to of the light signal.

• A. Longer wavelengths
• B. Frequency
• C. Intensity
• D. Dispersion or Spreading✓

Explanation: Explanation: Dispersion is a phenomenon in which the different wavelengths of light travel at different speeds through a fibre, causing the light pulses to spread out over time and space. This can result in overlapping of adjacent pulses, causing information loss and inaccuracies. This option is not correct because longer wavelengths generally suffer less from dispersion than shorter wavelengths. This option is also incorrect because the frequency of the light signal does not directly affect the dispersion of the signal in the fibre. This option is also incorrect because the intensity of the light signal can be amplified or attenuated by optical amplifiers or attenuators, but it does not directly affect the dispersion of the signal in the fibre.

Q194. 8, 10, 14, 18, _ , 34, 50 , 66:

• A. 24
• B. 25
• C. 26✓
• D. 27

Explanation: The increasing order is +2,+4, +4, +8, +16, +16 8 + 2= 10 10 + 4= 14 14 + 4 = 8 18 + 8= 26

Q195. If ‘-’ means ‘+’, ‘+’ means ‘-’, ‘*’ means ‘÷’ and ‘÷’ means ‘*’ then which of the following will be the correct equation?

• A. 10 + 5 - 14 ÷ 10 * 15 = 158
• B. 30 + 5 + 14 - 10 * 15 = 122
• C. 30 - 5 + 14 ÷ 10 * 15 = 162
• D. 30 * 5 - 4 ÷ 10 + 15 = 31✓
• E. None of these

Explanation: From option (d), 30 ÷ 5 + 4 * 10 - 15 = 6 + 40 - 15 = 46 - 15 = 31 Hence, option D is the correct answer.

Q196. Statements: 1. Dogs are cats. 2. Cats are birds. Conclusion: 1. Cats are dogs. 2. Dog are birds.

• A. Only conclusion I follows
• B. Only conclusion II follows✓
• C. Either I or II follows
• D. Neither I nor II follows

Explanation: If Dogs= cats and cats= birds then dogs are birds. The statement doesn’t mention anywhere that cats are dogs.

Q197. On the day Bilal is born,Jamila weighs more than Javed.Javed weighs less than Junaid.Of the three babies, Junaid weighs the most.If the first two statements are true, the third statement is

• A. True
• B. FALSE
• C. Uncertain✓
• D. None of these

Explanation: If junaid weighs more than javed there are two possiblities; junaid could weigh more or less than jamila hence its uncertain.

Q198. StatementIn a specific area of a country an acute famine have appeared COURSE OF ACTION: I. Major facilities of water and food should be provided straight away in that area. II. Financial support should be given to bothered individuals to the from the Government.

• A. Both of them follows
• B. None of them follow
• C. Only I follows✓
• D. Only II follows

Explanation: Famine means an extreme scarcity of food. If famine has occurred in an area, food and water should be supplied immediately as it will help save lives. Even though financial support is also necessary, food and water are more pivotal in a situation like this. Financial support is a secondary need.

Q199. Statement I: The children are being aggressive today.Statement II: There is no specific limit for children to use mobile screens.

• A. Statement I is the cause and II is the effect.
• B. Both of the statements are independent.✓
• C. Statement II is the cause and I is the effect.
• D. Both statements are the effects of some common cause.

Explanation: Based on the given statements: Statement I: The children are being aggressive today. Statement II: There is no specific limit for children to use mobile screens. It is not clear that either statement is the cause and the other is the effect. Also, there is no evidence provided in the statements to establish a clear cause-and-effect relationship between them. Therefore, we cannot determine a direct cause-and-effect relationship between the two statements. Additionally, both statements appear to be independent of each other, as there is no apparent link or logical connection between children being aggressive and the absence of a specific limit for children to use mobile screens The given information does not support any specific cause-and-effect relationship between the two statements or the existence of a common cause affecting both of them. Therefore, the correct answer is: Both of the statements are independent.