Balochistan Mdcat 2009 — Solved Past Paper with Answers

Q1. Which of the following is most similar in meaning to the given word INDICATE

• A. Design
• B. Show✓
• C. Agree
• D. Hide

Explanation: Show means to cause or allow to be seen; exhibit; display.

Q2. Pick Out the word which is wrong in the following sentence An usual cure for the flu is to drink plenty of liquid. No error

• A. An✓
• B. Usual
• C. The flu
• D. Plenty
• E. No error

Explanation: Words where ‘u’ is pronounced like ‘you’ then it is better to use ‘a’ instead of ‘an’

Q3. Choose the most appropriate word to complete the sentence _ the rain was enough this year, yet the crop yield of rice was not much

• A. Inspite
• B. Since
• C. Although✓
• D. Even

Explanation: Although 'Although' is always followed by 'yet'. It is used to show two contrary qualities or actions of a subject.

Q4. We complained _the manager of the restaurant_the food.

• A. of :about
• B. to: for
• C. to : about✓
• D. with : about
• E. to : for

Explanation: Explanation for this question will be added soon.

Q5. Make time underlines phrase correct. He is helping me typing my paper.

• A. Help me typing
• B. Help my typing
• C. helping me to typing✓
• D. Helping me to type
• E. not helping me typing

Explanation: Option c The -ing form emphasises the verb itself. The to-infinitive puts the emphasis more on the preference for, or the results of, the action

Q6. Glucose and fructose are _, that join together through glycosidic bond to form sucrose which is _.

• A. Monosacearides : Monosaecaride
• B. Monosaceari,des : Disaecaride✓
• C. Disaccarides : Monosaccaride
• D. Disaccarides : Disaccaride
• E. None of the above

Explanation: This is the correct option. Sucrose is a disaccharide composed of two different monosaccharides, glucose, and fructose.

Q7. Which of the following is a complex of globular protein with non-proteinaceous material?

• A. Collagen
• B. Egg albumen
• C. Hemoglobin✓
• D. Fibrinogen
• E. Keratin

Explanation: Haemoglobin is a globular protein that binds to a non-proteinaceous substance, haem, which carries oxygen. This material is known as a prosthetic group and influences the shape of the polypeptide.

Q8. Which one of the following statement is INCORRECT for antibodies?

• A. They are formed from plasma cells
• B. They are present in blood
• C. They are present in lymph
• D. They are present in saliva.✓

Explanation: Antibodies, also known as immunoglobulins, are primarily found in blood and lymph, where they play a crucial role in the immune system's response to infections and foreign substances. While antibodies can be found in various bodily fluids and secretions, including saliva, their primary location is not in saliva.

Q9. Which one of the following statements is NOT true for enzymes?

• A. They lower the activation energy
• B. They decrease the rate of reaction✓
• C. They are specific in their action
• D. They are present at the end of the reaction
• E. They are pH sensitive

Explanation: Enzymes, in fact, increase the rate of chemical reactions by lowering the activation energy required for the reaction to occur. They do not decrease the rate of a reaction.

Q10. Rough Endoplasmic Reticulum differs from smooth endoplasmic reticulum due to presence of;

• A. Ribosomes✓
• B. Lysosomes
• C. Mitochondria
• D. Golgi Bodies (Golgi Apparatus)

Explanation: Ribosomes are the correct answer. They are small structures that are present on the surface of the rough endoplasmic reticulum (RER), giving it a rough appearance. These ribosomes are the sites of protein synthesis.

Q11. Which one of the following is a correct Pair

• A. Mitochondria : provide barrier to cell
• B. Golgi apparatus : Synthesis of polysaccharide
• C. Ribosomes : Cell secretion✓
• D. Endoplasmie Reticulum : Provide energy to cell
• E. Lysosomes: Membrane bounded organelle which converts fats into sugar

Explanation: Ribosomes are cellular structures responsible for protein synthesis, not cell secretion.

Q12. The Heart Beat initiates at

• A. AV Node
• B. SA Node✓
• C. Purkinje Fibers
• D. Bundle of His

Explanation: The SA node is often referred to as the "natural pacemaker" of the heart. It is located in the right atrium and initiates the electrical impulse that controls the heart's rhythm. The SA node is responsible for starting each heartbeat.

Q13. Homeostasis means

• A. Maintenance of internal environment by depending on external environment to some extent
• B. Maintenance of a constant internal environment by depending on the external environment to some extent.✓
• C. Maintenance of internal environtnent by totally depending on external environment
• D. Maintenance of variable interrial,environnient by depending on external environment to some extent

Explanation: Homeostasis is the body's ability to maintain a relatively stable and balanced internal environment, despite changes in the external environment. It involves a dynamic equilibrium where the body can adjust to maintain conditions like temperature, blood pressure, and various physiological parameters within a certain range.

Q14. Exchange of gases between body and environment takes place in

• A. Pulmonary Vein
• B. Pulmonary Artery
• C. Bronchi
• D. Alveoli✓
• E. Trachea

Explanation: The alveoli are tiny air sacs in the lungs where the exchange of oxygen and carbon dioxide with the bloodstream takes place. They have a large surface area and are well suited for efficient gas exchange.

Q15. The correct sequence of parts of digestive canal is

• A. Mouth → Esophagus → Stomach → Small Intestine » Large Intestine✓
• B. Stomach » Small Intestine → Esophagus → Mouth.
• C. Small Intestine → Esophagus → Mouth → Stomach
• D. Large Intestine → Small Intestine → Esophagus → Mouth » Stomach.

Explanation: This sequence represents the typical path of food through the digestive system. Food enters the mouth, travels down the esophagus to the stomach, then proceegs to the small intestine for digestion and absorption of nutrients before passing into the large intestine for further processing and elimination.

Q16. Mushroom and yeast are the members of

• A. Kingdom Plantae
• B. Kingdom Animalia
• C. Kingdom Protista
• D. Kingdom Fungi✓
• E. Kingdom Monera

Explanation: Fungi are a kingdom of eukaryotic, heterotrophic organisms that includes mushrooms, yeast, molds, and more. They are characterized by their ability to break down and absorb nutrients from organic matter. Mushrooms are a well-known example of fungi.

Q17. Which one of the following is Endoparasite

• A. Ticks
• B. Mites
• C. Plasmodium✓
• D. Fleas
• E. Lice

Explanation: Plasmodium is an endoparasite responsible for causing malaria. It is a protozoan parasite that infects red blood cells and lives inside them.

Q18. The opening of stomata leads to I) increase in photosynthesis II) Increase in transpiration lll) Loss of chlorophyll

• A. I only
• B. ll only
• C. l and ll only✓
• D. l and lll only
• E. l, ll and lll

Explanation: (l) Increase in photosynthesis: Stomata are small openings in plant leaves and stems that allow the exchange of gases, including the intake of carbon dioxide (CO2) for photosynthesis. When stomata open, it allows more CO2 to enter the leaf, facilitating an increase in photosynthesis. (Il) Increase in transpiration: Transpiration is the loss of water vapor from the plant, primarily through the stomata. When stomata open to allow CO2 entry, it also leads to an increase in water loss (transpiration) as a result. (III) Loss of chlorophyll: Stomata openings do not directly lead to the loss of chlorophyll, which is essential for photosynthesis. Chlorophyll is present in chloroplasts within the plant cells and plays a critical role in capturing light energy for photosynthesis.

Q19. The loss of water in some plants by hyclathodes is called

• A. Guttation✓
• B. Transpiration
• C. Transportation
• D. Translocation

Explanation: Guttation is the process by which water is released from the tips or edges of leaves through specialized structures called hydathodes. This typically occurs at night when the plant's transpiration rate is low, and the root pressure forces water out of the hydathodes. Guttation results in the exudation of liquid water, often containing dissolved minerals, from the plant.

Q20. The conifers like pines are

• A. Gymnosperms✓
• B. Angiosperms
• C. Ferns
• D. Moss
• E. Bryophytes

Explanation: Gymnosperms are a group of seed-producing plants, which includes conifers like pines. They are characterized by their seeds that are not enclosed within fruits.

Q21. Which of the following in a part of pectoral girdle?

• A. Femur
• B. Patella
• C. Tibia and Fibula
• D. Glenoid Cavity✓
• E. Pubis

Explanation: The glenoid cavity is a part of the scapula (shoulder blade) and is involved in forming the shoulder joint. It is indeed a component of the pectoral girdle.

Q22. Which one of the following is correct sequence of taxonomic levels?

• A. Class, genus, family, order
• B. Genus, family, order, class
• C. Class, order, genus, family
• D. Family, order, class, genus✓

Explanation: This sequence is also not in the correct order. It begins with family, which is more specifia, and should start with broader categories.

Q23. Which one of the following endocrine gland and hormone Is NOT paired correctly?

• A. Adrenal Medulla : Norepinephrine
• B. Adrenal Cortex : Glucdcorticold
• C. Pituitary gland : Estrogen✓
• D. Pancreas : Insulin
• E. Parathyrold:Paratharmone

Explanation: The pituitary gland is responsible for producing various hormones, but estrogen is not primarily produced by the pituitary gland. Estrogen is mainly produced by the ovaries in females and plays a significant role in the female reproductive system.

Q24. Which one of the following is WRONG about human female reproductive system?

• A. Leutal phase is absent✓
• B. Menstrual phase is of 4 to 5 days
• C. Menstrual cycle is of 28 + 5 days
• D. None of the above

Explanation: This statement is incorrect. The luteal phase is a crucial part of the menstrual cycle, which occurs after ovulation when the corpus luteum forms from the ovarian follicle that released an egg. The corpus luteum produces progesterone, and this phase is essential for preparing the uterine lining for potential implantation of a fertilized egg.

Q25. Which one of the following describes function of insulin?

• A. It breaks down blood glucose
• B. It catalyzes the condensation of glucose to form glycogen
• C. It enables glucose to enter cells.✓
• D. It prevents glucose from being excreted by the kidney

Explanation: This is the central function of insulin. Insulin binds to receptors on cell membranes, allowing glucose to enter cells for energy production and storage.

Q26. In prophase of mitosis, which one of th'eIollowing events occur in animal cells but not in plant cells?

• A. Centrioles migrate to opposite sides of the nucleus✓
• B. Chromosomes become invisible due to condensation
• C. Homologous chromosomes do not associate
• D. The nuclear envelope (membrane) breaks down
• E. Nucleoli in the nucleus disappear

Explanation: Centrioles are a part of the animal cell's centrosome and play a role in organizing the spindle fibers during cell division. Plant cells do not have centrioles in the same way animal cells do, so this specific migration of centrioles does not occur in plant cells.

Q27. Sweat Pea belongs to

• A. Family Rosaceae
• B. Family Roseaceae
• C. Family Solanaceae
• D. Family Mimoaceae
• E. Family Fabaceae✓

Explanation: The Fabaceae family, also known as the Leguminosae family, includes plants like peas, beans, and, indeed, Sweet Pea (Lathyrus odoratus). So, Sweet Pea belongs to the Fabaceae family.

Q28. The Protozoa digests the cellulose living in the gut of termites. This is an example of

• A. Mutualism✓
• B. Parasitism
• C. Commensalism
• D. Competition

Explanation: Mutualism is a type of symbiotic relationship where both species benefit from their association. In the case of termites and protozoa, termites provide a protected environment and food source (cellulose) for protozoa, while protozoa aid termites in digesting cellulose, which is a complex carbohydrate that termites can't break down on their own.

Q29. Correct Definition of Niche is

• A. Group of individuals living together and compete for existence
• B. Role played by a species in a community in a particular environment✓
• C. Different populations existing in the same place
• D. Individuals interbreeding with each other

Explanation: This is the correct definition. A niche is the ecological role a species plays in its community, including its interactions with other species and its use of resources.

Q30. The process by which single stranded RNA is synthesized from double stranded DNA is called

• A. Translation
• B. Transportation
• C. Transcription✓
• D. Transpiration

Explanation: Transcription is the process of synthesizing RNA from a DNA template. It involves the creation of an RNA molecule complementary to a segment of DNA.

Q31. If the anticodon in titNA is UAG, th rresponding code for it in DNA would he

• A. UAG
• B. TAG✓
• C. COT
• D. GCT

Explanation: In the genetic code, a codon (a sequence of three nucleotides) in mRNA corresponds to an anticodon in tRNA. In this case, the anticodon UAG in tRNA corresponds to the codon TAG in DNA. The relationship between DNA codons and RNA codons (anticodons) is a key part of the genetic code.

Q32. The bonding which exists between A, T and C, G is called

• A. Covalent Bonding
• B. Ionic Bonding
• C. Hydrogen Bonding✓
• D. Phosphodiester Bonding

Explanation: Hydrogen bonding is the specific type of bonding that occurs between complementary base pairs in DNA. Adenine (A) forms hydrogen bonds with thymine (T), and cytosine (C) forms hydrogen bonds with guanine (G).

Q33. Which one of the following is genetic Mutation?

• A. Frame shift✓
• B. Silent
• C. Point
• D. All of the above

Explanation: A frame-shift mutation is a type of genetic mutation where the insertion or deletion of nucleotides shifts the reading frame of a gene, leading to a change in the resulting protein.

Q34. Hardy Weinberg Theorem gives following equation P2 +2pq + q2. What is 'P' in this equation?

• A. Frequency of dominant alleles
• B. Frequency of recessive alleles✓
• C. No of alleles
• D. All of the above

Explanation: "P" represents the frequency of the dominant allele, "a" represents the frequency of the recessive allele, and "2pa" represents the frequency of heterozygous individuals.The "frequency of recessive alleles" is represented by "a" in the equation. The theorem describes the relationship between allele frequencies in a population that is not experiencing evolution, where "p2" represents the frequency of homozygous dominant individuals, and y "a2" represents the frequency of homozygous dominant individuals, and "q2" represents the frequency of homozygous recessive individuals.

Q35. Pepsin is a/an _ which is secreted by _.

• A. Enzyme: stomach✓
• B. Hormone: stomach
• C. Enzyme: Intestine
• D. Hormone: Intestine

Explanation: Pepsin is an enzyme that is secreted by the stomach. It plays a crucial role in the digestion of proteins by breaking them down into smaller peptide fragments.

Q36. Ascaris is the organism of which Phylum

• A. Annelida
• B. Nematoda✓
• C. Platyhelminthes
• D. Echinodermata

Explanation: Ascaris is a genus of parasitic nematode worms, commonly known as roundworms. They are classified within the Phylum Nematoda, which is a diverse group of roundworms. These organisms often parasitize the intestines of animals, including humans.

Q37. Arthropods have following organs for respiration EXCEPT

• A. Book Lungs
• B. Mantle
• C. Gills
• D. Trachea✓

Explanation: Arthropods use tracheal systems for respiration. Tracheae are a network of tubes that carry air directly to cells. Insects are a well-known group of arthropods that use tracheae.

Q38. Which one of the following is NOT a sexually transmitted disease?

• A. Gonorrhea
• B. Syphilis
• C. Meningitis✓
• D. AIDS
• E. Genital Herpes

Explanation: Meningitis is not a sexually transmitted disease. It is an inflammation of the meninges (protective membranes)surrounding the brain and spinal cord. It is usually caused by infection with bacteria, viruses, or other pathogens.

Q39. Cerebellum is involved in

• A. Knee and elbow jerks
• B. Nerve impulse transmission
• C. Homeostasis
• D. Muscle Movement✓

Explanation: The cerebellum plays a key role in the coordination and fine control of muscle movements, making it the most relevant option.

Q40. Which of the following muscle is striated but involuntary?

• A. Urinary bladder wall
• B. Intestinal wall
• C. Bone muscle
• D. Cardiac muscle✓
• E. Smooth muscles

Explanation: Cardiac muscle is both striated has a striped appearance under a microscope) and involuntary. It makes up the walls of the heart and is responsible for pumping blood.

Q41. The plant which have adapted life to high salt concentration environment are

• A. Hydrophytes
• B. Halophytes✓
• C. Mesophytes
• D. Xerophytes

Explanation: Halophytes are plants that have adapted to high salt concentration environments, such as saline soils or coastal areas.

Q42. Which one of the followings is function of progesterone?

• A. It inhibits secretion of ESH
• B. It stimulates ovulation
• C. It causes the appearance of secondary sexual characteristics
• D. It prepares the uterus wall for implantation✓
• E. It is secreted by the pituitary gland

Explanation: This is the primary function of progesterone. It helps create a favorable environment in the uterus for the potential implantation of a fertilized egg.

Q43. Which of the following is a type of learning behavior in which organism does not respond to harmless and repeated stimuli?

• A. Imprinting
• B. Habituation✓
• C. Conditioned reflex type 1
• D. Insight learning

Explanation: Habituation is a form of non-associative learning where an organism becomes less responsive to repeated and harmless stimuli. It's a way for an organism to filter out unimportant information.

Q44. In DNA double helix, the Thymine is paired with _, cytosine is paired with _

• A. Thymine ; Guanine
• B. Adenine: Guanine
• C. Adenine: Cytosine
• D. Cytosine: Adenine✓

Explanation: The base pairing in DNA is specific: Adenine (A) always pairs with Thymine (T), and Cytosine (C) always pairs with Guanine (G). So, the correct pairing for Thymine (T) is Cytosine (C).

Q45. In sweet pea plants, the allele for allness is (T) and for shortness is (t) and similarly for green color is (G) an bit; (g). A female plant is TtGg and mate plant is TTGG, what kinds of gametes are produced by two plants

• A. Female TG, Tg, 1G, 1g: Male TTg
• B. Female Tg, Tg and Male Tg, TG, 1G, 1g
• C. Female and male both Tg, Tg
• D. None of the above✓

Explanation: This is the correct option. None of the provided options accurately represent the alleles of the female and male plants. The correct representation of the female and male plants' alleles is as follows: Female (TtGg): TG, Tg, 1G, 1g Male (TTGG): TG, TG To determine the kinds of gametes produced by the given parents, let's examine the alleles for each trait: • Female (TtGg): The female has one allele for tallness (T), one allele for shortness (t), one allele for green color (G), and one allele for yellow color (g). • Male (TTGG): The male has two alleles for tallness (T), two alleles for green color (G), and no alleles for shortness (t) or yellow color (g). Now, let's consider the possible combinations of gametes for each parent: • Female (TtGg): Can produce gametes containing the alleles TG, Tg, 1G, and 1g. • Male (TTGG): Can produce gametes containing the alleles TG and TG.

Q46. Which of the following terms gives the fact that a gone exists as two alternative forms?

• A. Allele✓
• B. Genome
• C. Genepool
• D. Phenotype
• E. None

Explanation: An allele is an alternative form of a gene that occupies a specific location on a chromosome. Alleles can vary in their DNA sequence, resulting in different traits or characteristics.

Q47. X normral /Y : X heamophilic/X normal What is the probability of children to be male?

• A. 0%
• B. 25%
• C. 50%✓
• D. 75%
• E. 100%

Explanation: The probability of children being male is 50% because they inherit an X chromosome from the mother and either an Xor Y chromosome from the father.

Q48. X normral / Y : X heamophilic / X normal What is the probability of female offsprings to be heamophitic

• A. 0%✓
• B. 25%
• C. 50%
• D. 75%
• E. 100%

Explanation: The probability of female offspring being hemophilic is 0% because hemophilia is a recessive X-linked genetic disorder. In question #42, it was indicated that the father is normal (X normal Y), so he does not carry the hemophilic allele. Thus, female offspring cannot inherit two hemophilic alleles (one from each parent) and will not be affected by hemophilia.The probability of female offspring being hemophilic is 0%. This is because, in the case of the provided information, none of the male offspring have hemophilia, and therefore, the mother does not produce female offspring with two hemophilic alleles (XX hemophilic). The X-linked recessive trait does not manifest in any of the children, male or female.

Q49. Blood flows from right atrium to

• A. Left atrium✓
• B. Left ventricle
• C. Right ventricle:
• D. Pulmonary vein
• E. Aorta

Explanation: Blood flows from the right atrium to the left atrium through the atrioventricular septum.

Q50. Tricuspid valve is present between

• A. Right atrium and right ventricle✓
• B. Left atrium and left ventricle
• C. Right ventricle and pulmonary artery
• D. Left atrium and aorta
• E. Vena cava and right atrium

Explanation: The tricuspid valve is located between the right atrium and the right ventricle and helps regulate the flow of blood from the atrium to the ventricle.

Q51. Which or the following metals is most reactive?

• A. Na✓
• B. Mg
• C. Cu
• D. Au
• E. Cl

Explanation: Because sodium (Na) is the most reactive metal. The reactivity of metals generally increases as you move down and to the left on the periodic table. Sodium is located in Group 1 of the periodic table, which is known as the alkali metals group. Alkali metals are highly reactive due to their low ionization energy and their tendency to lose one electron to achieve a stable electron configuration.Sodium is highly reactive and can react vigorously with water, producing hydrogen gas and sodium hydroxide. It is stored under oil to prevent contact with moisture and air.

Q52. The oxidation state of 'Mn' in compound KMnO4 is

• A. +7✓
• B. +4
• C. 0
• D. -4
• E. -7

Explanation: In KMnO4 (potassium permanganate), potassium (K) is in Group 1 of the periodic table, and its oxidation state is +1. Oxygen (O) is usually assigned an oxidation state of -2 in most compounds. The sum of the oxidation states in a compound should equal its overall charge. In KMnO4, the overall charge is 0 (since it's a neutral compound). Let × be the oxidation state of manganese (Mn). So, we have: (+1) + × + 4(-2) = 0 Simplifying the equation: +1 + x-8=0 Simplifying the equation: +1+x-8=0 × - 7 = 0 x= +7 Therefore, the oxidation state of manganese (Mn) in KMnO4 is +7. Here's a representation of the structure of potassium permanganate (KMnO4): In this structure, each oxygen atom is connected to manganese (Mn) through a single bond, and there are four oxygen atoms bonded to manganese. The oxidation state of manganese is indeed +7 in this compound.

Q53. How many hydrogekatoms can be replaced in compound C6H5CH2OH when dissolved in excess of water?

• A. 1✓
• B. 2
• C. 3
• D. 4
• E. 8

Explanation: The compound thay is mentioned,appears to be ethanol (C2H5OH). When ethanol (C2H5OH) is dissolved in excess water (H2O), it can undergo acid-base reactions, specifically alcoholysis. In this reaction, the hydrogen (H) atoms in the hydroxyl (-OH) group of ethanol can be replaced by water molecules. Here's how the reaction occurs: 1. Ethanol (C2H5OH) in water: CH3CH2OH + H2O 2. In this reaction, one of the hydrogen atoms (H) in the hydroxyl group (-OH) of ethanol is replaced by a water molecule (H2O). This forms a hydronium ion (H3O+): H3CH2O + H3O+ 3. The hydronium ion (H3O+) represents an acidic solution. It can further react in water, creating a dynamic equilibrium with the formation of hydronium ions and hydroxide ions (OH-): H3O+= H2O + H2O 4. This equilibrium results in a slight increase in the concentration of both hydronium ions (H30+) and hydroxide ions (OH-) in the solution, making it slightly acidic. So, to answer your question, in excess water, the hydrogen atom (-H) in the -OH group of ethanol can be replaced by water molecules. Since there are two -OH groups in ethanol (C2H50H), two hydrogen atoms can be replaced in total. The correct answer is (A) 1. The other options B C D E are incorrect because they suggest a greater number of hydrogen atoms being replaced than is actually possible in ethanol. Ethanol contains only one hydroxyl group per molecule, so only one hydrogen atom in the -OH group can be replaced during the reaction with water.

Q54. If there were three electrons in each orbital, then the no of elements in 4t1' period would be

• A. 8
• B. 18
• C. 27✓
• D. 36

Explanation: Because The number of elements in a period of the periodic table is determined by the number of orbitals available in that period. Each orbital can hold a maximum of two electrons due to the Pauli Exclusion Principle. Therefore, to determine the number of elements in the 41st period, you need to know how many orbitals are present in that period. In general, the number of orbitals in each period can be calculated using the formula 2n2, where "n" is the period number. The other options B C D E are incorrect because However, it's important to note that elements beyond the 7th period are theoretical and not observed in nature due to the extreme conditions required for their existence. The periodic table as we know it ends at the 7th period with element number 118 (Oganesson). Therefore, while theoretically, there could be 6724 elements in the 41st period, in reality, the periodic table is limited to the elements we've discovered up to the 7th period.

Q55. If a gas is Contained in a container at pressure of 1atm, when the temperature is 300k, what would be the pressure if the temperature of gas is increased to 600K?

• A. 1atm
• B. 2atm✓
• C. 3atm
• D. 4atm
• E. None

Explanation: The relationship between pressure (P) and temperature (T) of a gas at constant volume is described by Gay-Lussac's Law, which states that: P1/Т1 = P2/T2 Where: P1 = Initial pressure T1 = Initial temperature (in Kelvin) P2 = Final pressure T2 = Final temperature (in Kelvin) In this case: P1 = 1 atm T1 = 300 K T2 = 600 K (temperature increased to 600K) Now, plug these values into the equation: 1 atm / 300 K = P2 / 600 K To find P2 (the final pressure), you can rearrange the equation: P2 = (1 atm / 300 K) * 600 K P2 = (1/300) * 600 atm P2 = 2 atm rearrange the equation: P2 = (1 atm / 300 K) * 600 K P2 = (1/300) * 600 atm P2 = 2 atm So, when the temperature of the gas is increased to 600 K, the pressure becomes 2 atm. The other options are incorrect A C D E because by using above formula the answer comes 2 atm

Q56. Tile Ka for acetic acid is 2 x 10N. What is the pH of 0.5M acetic acid solution?

• A. 1.0
• B. 2.0
• C. 2.5✓
• D. 3.0
• E. 7.0

Explanation: The pH of a weak acid solution, such as acetic acid (CH3COOH), can be calculated using the expression for the acid dissociation constant (Ka) and the concentration of the acid. The relationship between pH, Ka, and the concentration of the acid ([HA]) for a weak acid is given by the following equation: pH = -log(Ka* [HA]) In this case: Ka = 2 × 10-5 (given) [HA] = 0.5 M (concentration of acetic acid) Now, plug these values into the equation By using this equation the above answer is C Thats why all other options A B D E are incorrect

Q57. How many single bonds are there in a molecule of CO2?

• A. None✓
• B. 1
• C. 2
• D. 3
• E. 4

Explanation: In a molecule of carbon dioxide (CO2), there are no double bonds or single bonds as in organic molecules. Instead, it consists of one carbon atom double-bonded to two oxygen atoms. Each of these bonds is a double bond, not a single bond or triple bond. Here's a simplified structural representation of CO2 In this representation, the lines between the atoms represent the double bonds. There are no single bonds (one line) or triple bonds (three lines) in CO2. So, the correct answer to your question is A

Q58. 2Al(s) + Fe2O3(s) Al2O3(s) + 2Fe(s) if 80gm of Al and 80gm of Fe2O3 are combined. What is the maximum numbers of moles of Fe that can be produced?

• A. 0.5
• B. 1✓
• C. 2
• D. 3
• E. 4

Explanation: The balanced chemical equation you provided represents the reaction between aluminum (AI) and iron(IlI) oxide (Fe2O3) to produce aluminum oxide (Al2O3) and iron (Fe). The coefficients in the balanced equation indicate the stoichiometric ratios of the reactants and products. The balanced equation is: 2Al(s) + Fe2O3(s) -> Al2O3(s) + 2Fe(s) Now, let's calculate the maximum number of moles of Fe that can be produced when 80 grams of Fe2O3 and some grams of Al Now, let's calculate the maximum number of moles of Fe that can be produced when 80 grams of Fe2O3 and some grams of Al are combined. We'll use the concept of limiting reactants to determine this. 1. Calculate the molar mass of Fe2O3: Fe2O3 = 2(55.85 g/mol Fe) + 3(16.00 g/mol0) = 159.7 g/mol 2. Calculate the moles of Fe2O3 in 80 grams: Moles of Fe2O3 = Mass (g) / Molar mass (g/mol) Moles of Fe203 = 80 g / 159.7 g/mol ~0.501 moles Now, let's consider the balanced chemical equation. According to the equation, 2 moles of Al react with 1 mole of Fe2O3 to produce 2 moles of Fe. This means that for every mole of Fe2O3, we can produce 2 moles of Fe. 1. Calculate the maximum moles of Fe that can be produced from 0.501 moles of Fe2O3: Moles of Fe = 2 × Moles of Fe2O3 Moles of Fe = 2 × 0.501 moles ~ 1.002 moles So, the maximum number of moles of Fev that can be produced is approximately 1.002 moles

Q59. Which of the following will dolinitely occur if quantity of acetic; acid Is added to a solution of potassium hydroxide at pH 117

• A. The number of lice protons per liter of solution will increase
• B. Titration will tend to neutralize the solution✓
• C. The acetic acid will act as a weak base
• D. Acetate ion will precipitate out or solution
• E. The pH will remain constant

Explanation: The reaction between acetic acid and potassium hydroxide is a neutralization reaction. It results in the formation of water and the acetate ion, which is the conjugate base of acetic acid.СНЗСООН + КОН -> CH3COO- + H2O • This process tends to neutralize the solution, moving it closer to a neutral ph.

Q60. The reaction between Kl and CuSO4 results in

• A. The precipitation of CuO
• B. Separation of metallic Cu
• C. Formation or K2SO4 with l2 evolved
• D. Iodine replaces SO4✓

Explanation: In the reaction between potassium iodide (KI) and copper(II) sulfate (CuSO4), a single displacement or replacement reaction occurs. Iodine from KI replaces the sulfate ion (SO42-) in copper sulfate (CuSO4) to form copper iodide (CuI) and potassium sulfate (K2SO4).The balanced chemical equation for this reaction is: 2KI + CuSO4 → CuI + K2SO4 Iodine replaces the sulfate ion in this reaction, leading to the formation of copper iodide.

Q61. What will happen when the electrodes are dipped In a solution of glucose?

• A. The bulb will light up
• B. The bulb will remain off.✓
• C. The bulb will first light up and then will become off
• D. The circuit will break

Explanation: Explanation for this question will be added soon.

Q62. Which is true regarding an aqueous solution of H2PO4 at 25°C?

• A. It has a very large acid ionization constant
• B. It has a bitter taste
• C. The concentration of (OH-) > 1.0 × 10-7M
• D. It is a very weak electrolyte✓
• E. It can be formed by the reaction of V metal oxide and water

Explanation: The correct statement (D) indicates that HCIO is a very weak electrolyte. This means that it only partially ionizes in aqueous solution, producing a relatively low concentration of ions. It does not conduct electricity as effectively as strong acids.

Q63. A vessel containing 0.28g of N2 and occupies volume of 0.56L, if another gas at same temperature and in sameNessel occupies 0.44L. Then what is the molecular mass of gas?

• A. 0.22g
• B. 0.35g✓
• C. 0.80g
• D. 0.96g
• E. 1g

Explanation: To find the molecular mass of the gas, we can use the ideal gas law: PV = ART Where: P = pressure V = volume n = number of moles R = universal gas constant T = temperature (in Kelvin) First, let's find the number of moles (n) for both gases. We'll assume that the pressure and temperature remain constant For the first gas: n1 = (mass1) / (molar mass1) Given that the mass of nitrogen (N) is 0.28g, and the molar mass of nitrogen is approximately 14g/mol, we can calculate n1:n1 = 0.28g / 14g/mol = 0.02 mol Now, for the second gas, we can use the same equation: n2 = (mass2) / (molar mass,) Let's call the molar mass of the second gas M2 (in grams per mole). Given that the second gas occupies 0.44L in the same vessel, we can set up a ratio: (n2) / (ni) = (V 1) / (V2) Where V1 is the initial volume (0.56L) and V2 is the final volume (0.44L). Also, n, = 0.02mol. (n.) / (0.02 mol) = (0.56L) / (0.44L) Where Vi is the initial volume (0.56L) and V2 is the final volume (0.44L). Also, n, = 0.02mol. (n2) / (0.02 mol) = (0.56L) / (0.44L) Solving for n2: n2 = 0.02 mol * (0.56L / 0.44L) = 0.35 mol

Q64. Based on the table above, which of the following is most likely to be the first ionization energor potassium.

• A. 536 KJ/mole
• B. 504 KJ/mole✓
• C. 419 KJ/mole
• D. 391 KJ/mole
• E. 358 KJ/mole

Explanation: This is the most likelv first ionization energy for potassium because it's slightly higher than sodium's value, consistent with the trend across the ionization energy tor potassium because it's slightly higher than sodium's value, consistent with the trend across the periodic table. Lets analayze incorrect answers The ionization energy generally increases across a period (from left to right) and decreases down a group (from top to bottom) in the periodic table. This is due to the increasing number of protons and electrons, which results in a stronger attraction between the electrons and the nucleus as you move across a period. Potassium (K) is in the same group as sodium (Na), which means they have similar electron configurations. Sodium (Na) has an ionization energy of 520 KJ/mole. Since potassium is in the same group and is just to the right of sodium in the periodic table.

Q65. Which of the following molecular formula is correctly paired with its empirical formula?

• A. C6H6 : C2H3✓
• B. С2Н6: CH
• C. C6H6: CH
• D. CH2: CH
• E. None

Explanation: The empirical formula (CH) represents the simplest whole number ratio of atoms in this compound, and it's also the molecular formula since there's only one carbon (C and one hydrogen (H) in the molecule. To determine which molecular formula is correctly paired with its empirical formula, you need to understand the concept of empirical and molecular formulas. The empirical formula represents the simplest whole number ratio of atoms in acompound. The molecular formula represents the actual number of atoms of each element in a molecule

Q66. Which 'of the following have strongest C-C bond?

• A. C2H2✓
• B. C2H4
• C. C2H6
• D. C3H8
• E. C4H10

Explanation: This molecule contains a triple bond between the two carbon atoms. Triple bonds are the strongest, so C2H2 has the strongest C-C bond. The strength of a C-C bond depends on the type of bond present between the carbon atoms. In organic chemistry, there are single, double, and triple bonds between carbon atoms, with triple bonds being the strongest.

Q67. A liquid has volume 103ml when pressure is 763 mm Hg and at a temperature of 27°C, the pressure of liquid decreases to 721 mm Hg. Keeping Temperature constant, what will be the new volume of the gas

• A. 106
• B. 109✓
• C. 120
• D. 114
• E. 104

Explanation: To solve this problem, we can use the combined gas law, which relates the initial and final conditions of a gas when temperature remains constant: (P1 * V1) = (P2 * V2) Where: P1 = initial pressure V1 = initial volume P2 = final pressure V2 = final volume Given: Initial volume (V1) = 103 ml Initial pressure (Pi) = 763 mm Hg Final pressure (P2) = 721 mm Hg Temperature remains constant. We need to find V2 (the new volume). Let's plug in the values into the combined gas law: (763 mm Hg * 103 L) = (721 mm Hg * V2) Now, solve for V2: V2 = (763 mm Hg * 103 mL) / 721 mm Hg V2 ~ 109.19 mL

Q68. The formula for calcium nitrate is Ca(NO3)2. What is its approximate formula weight?

• A. 64amu
• B. 164 amu✓
• C. 240 amu
• D. 310 amu
• E. 380 amu

Explanation: To calculate the approximate formula weight (also known as molar mass) of calcium nitrate (Ca(NO3)2), you need to add up the atomic masses of all the atoms in the formula. • The atomic mass of calcium (Ca) is approximately 40 amu. • The atomic mass of nitrogen (N) is approximately 14 amu. • The atomic mass of oxygen (0) is approximately 16 amu. Now, we have two nitrogen atoms and six oxygen atoms in the formula. Molar mass of Ca(NO3)2 = (1 * Ca) + (2 * N)+ (6 * 0) Molar mass of Ca(NO3)2 = (1 * 40 amu) + (2* 14 amu) + (6 * 16 amu) Molar mass of Ca(NO3)2 = 40 amu + 28amu + 96 amu Molar mass of Ca(NO3)2 = 164 amu So, the approximate formula weight of calcium nitrate (Ca(NO3)2) is approximately 164 amu.

Q69. When ethane reacts with 6M of CI, thou which one of the following products are obtained

• A. Chlorine replaces hydrogen✓
• B. Hexachloroethane is formed
• C. No Reaction Occurs
• D. Explosion occurs

Explanation: When ethane (C2H6) reacts with chlorine (CI2), a substitution reaction can occur in which chlorine replaces hydrogen atoms in ethane. This reaction is known as chlorination. Here's the balanced chemical equation for this reaction:C2H6 + Cl2 -> C2H5Cl + HCI In this reaction, one or more hydrogen atoms in ethane (C2H6) are replaced by chlorine atoms from CI2. The product formed is ethyl chloride (C2H5CI), and hydrogen chloride (HCI) is also produced as a byproduct.So, the correct answer is (A) Chlorine replaces hydrogen, and the product obtained is ethyl chloride (C2H5CI).Here's a simplified representation of the reaction:

Q70. Two different sodium atoms or ions may differ in all of tho following ways EXCEPT

• A. The number of electrons outside their nuclei
• B. The overall charge they carry
• C. Their mass number
• D. The number of neutrons in their nuclei✓
• E. The number of protons in their nuclei

Explanation: The number of neutrons in their nuclei, because different sodium isotopes can indeed have different numbers of neutrons in their nuclei, but the number of protons in the nucleus (atomic number) is always 11 for sodium.

Q71. Which of the following is a chemical change?

• A. Rusting of iron
• B. Mixing of salt and water
• C. Burning of paper
• D. Melting of ice
• E. Both A and C✓

Explanation: A chemical change, also known as a chemical reaction, involves the formation of new substances with different chemical properties. Let's examine the options: A) Rusting of iron: This is a chemical change. When iron reacts with oxygen and moisture in the air, it forms iron oxide, commonly known as rust. Rust is chemically different from iron, and this process represents a chemical reaction. C) Burning of paper: This is also a chemical change. When paper burns, it undergoes a chemical reaction with oxygen in the air,producing carbon dioxide, water vapor, and other products. The original paper is transformed into new substances with different chemical properties.

Q72. Aqueous solution of barium chloride and sodium sulfate react to form an insoluble white solid

• A. BaSO4(s)✓
• B. Na2CO3(s)
• C. BaCI2(s)
• D. NaCI(s)
• E. BaNa2SO4(s)

Explanation: The chemical equation for the reaction between barium chloride (BaCI2) and sodium sulfate (Na2SO4) in aqueous solution is as follows: BaCl2(aq) + Na2SO4(aq) -> BaSO4(s) +2NaCI(ag) In this reaction, a white insoluble solid, which is barium sulfate (BaSO4), is formed.When barium chloride (BaCI2) and sodium sulfate (Na2SO4) react in aqueous solution, they produce barium sulfate (BaSO4) as an insoluble white solid. This is a precipitation reaction, and BaSO4 is indeed a white solid.

Q73. Which of the following contain an ionic bond?

• A. CO2
• B. HF
• C. HO
• D. CSF✓
• E. HCI

Explanation: lonic bonds typically form between elements with significantly different electronegativities. In an ionic bond, one atom donates electrons (becomes a cation), while the other atom accepts electrons (becomes an anion). Cesium fluoride is a substance composed of cesium and fluoride elements, which are different in type; cesium is metal and fluoride is a nonmetal. Considering that a metal and a nonmetal bonding results mostly in ionic compounds

Q74. Which of the following is surrounded by maximum number of water molecules?

• A. SO2
• B. MgCI2✓
• C. NaCI
• D. CuSO4

Explanation: Magnesium chloride is an ionic compound consisting of Mg2+ and CI- ions.When it dissolves in water, it dissociates into ions, and each ion is surrounded by a sphere of water molecules due to electrostatic attraction. So, ionic compounds like MgCI2 can be surrounded by a large number of water molecules.

Q75. A 0.2M solution of 21.6mI NaOH is reacted with 25ml of HCI. What is the molarity of HCl?

• A. 0.678M(acid)
• B. 0.798 M (acid)
• C. 0.896 M (acid)
• D. 0.978 M (acid)
• E. 0.172 M (acid)✓

Explanation: To find the molarity of HCI (hydrochloric acid) after it reacts with NaOH (sodium hydroxide), we can use the concept of neutralization reactions. In a neutralization reaction between an acid and a base, the moles of acid reacting with moles of base should be equal. We can use the equation: Molarity (M) = (moles of solute) / (volume of solution in liters) First, we need to find the moles of NaOH in the 21.6 mL solution: Moles of NaOH = Molarity × Volume (in Moles of NaOH = Molarity × Volume (in liters) Moles of NaOH = 0.2 M × (21.6 mL / 1000 mL/L) Moles of NaOH = 0.00432 moles Now, since HC reacts with NaOH in a 1:1 ratio, the moles of HCI should be the same as the moles of NaOH after the reaction. Therefore, we have 0.00432 moles of HCI. Next, we need to find the molarity of HCI in the 25 mL solution: Molarity (HCI) = (moles of HCI) / (volume of solution in liters) Molarity (HCI) = 0.00432 moles / (25 mL /1000 mL/L) Molarity (HCI) = 0.172 M So, the molarity of HCI after the reaction is 0.172 M.

Q76. What is the ratio of [H+] of a solution of pH = 4 to the [H+] of a solution of pH = 7?

• A. 200:1
• B. 500:14
• C. 1000:1✓
• D. 1:1
• E. 10000:1

Explanation: The pH of a solution is a measure of its acidity or alkalinity and is defined as the negative logarithm (base 10) of the concentration of hydrogen ions ([H+]) in the solution. The relationship is given by the formula: pH = -log10([H+]) To find the ratio of [H+] of a solution at pH 4 to a solution at pH 7, we can calculate the [H+] for each pH value and then determine the ratio. For pH = 4: pH = -log10([H+]) 4 = -log10([H+]) Now, we need to find [H+]. To do that, we can take the antilog (10 raised to the power of -4) of both sides: [H+1= 10-4) For pH = 7: pH = - log10([H+]) 7 = -log10([H+]) Again, we need to find [H+]. To do that, we can take the antilog (10 raised to the power of -7) of both sides: [H+]= 10(-7) Now, we can calculate the ratio: Ratio = [H+] at pH 4 / [H+] at pH 7 Ratio = (10(-4)) / (10(-7)) When you divide two numbers with the same base (10 in this case) and different exponents, you subtract the exponents: Ratio = 10(-4 - (-7)) Ratio = 103 Ratio = 1000

Q77. Which of the following will be the most conductive electrically?

• A. Sugar dissolved in water
• B. Salt water✓
• C. Salt dissolved in organic solvent
• D. An oil and water mixture
• E. None

Explanation: Because it contains ions (sodium and chloride ions) that can carry an electric current. The electrical conductivity of a solution is primarily determined by the presence of ions. Ions are electrically charged particles that can carry an electric current.

Q78. What factors determine whether or not two liquids are miscible?

• A. Molecular size
• B. Molecular polarity✓
• C. Density
• D. Both B and C

Explanation: The miscibility of two liquids strongly depends on their polarities. In general, polar and nonpolar liquids are not miscible, while a polar liquid can usually be mixed with another polar liquid, and a nonpolar liquid with another nonpolar liquid. Choice A, molecular size, and choice C, the density of a liquid, do not directly affect the miscibility (although choice C should remind you that two immiscible liquids will form separate layers, with the denser liquid on the bottom). Thus, B is the only correct choice.

Q79. When 200g of MgCl2 is added to 1Kg of water, what is the moiality of the solution?

• A. 200/(244+71)
• B. 0.200/(24+71)✓
• C. 0.2(24+71)
• D. 0.200
• E. 200

Explanation: To calculate the molality of a solution, you need to know the moles of the solute (in this case, MgCI2) and the mass of the solvent (water) in kilograms. 1. First, let's find the moles of MC|2: • Given mass of MgCl2 = 200 grams • Molar mass of MgCl2 = 24.305 g/mol (for Mg) + 2 * 35.453 g/mol (for CI) =94.211 g/mol • Moles of MgC12 = (200 g) / (94.211 g/mol) ~ 2.121 moles 2. The mass of the solvent (water) is given as 1 kg, which is equal to 1000 grams. 3. Now, you can calculate the molality (m) using the formula: Molality (m) = (moles of solute) / (mass of solvent in kg) Molality (m) = (2.121 moles) / (1000 g /1000) kg = 0.002121 mol/kg So, the molality of the solution is approximately 0.002121 mol/kg. The closest answer choice is (B)0.200/(24+71), which represents the correct calculation for the molality

Q80. In order to make a buffer solution, a weak monoprotic acid could be added to

• A. Another acid
• B. Another base
• C. Conjugate base✓
• D. Its conjugate acid
• E. A strong base

Explanation: To create a buffer solution, you need a weak acid and its conjugate base. This pair of components helps the solution resist changes in pH when an acidic or basic substance is added. The weak acid neutralizes added base, and its conjugate base neutralizes added acid.

Q81. If frequency of a body under simple harmonic motion remains constant, then the accoluration of body is directly proportional to

• A. Velocitv
• B. Amplitude
• C. Displacement✓
• D. None
• E. .

Explanation: a = -ω2x Where: "a" is the acceleration of the body. "x" is the displacement of the body from its equilibrium position. "ω" (omega) is the angular frequency, which is related to the frequency "f" by the equation ω = 2πf. This equation shows that the acceleration "a" is directly proportional to the displacement "x" and is also proportional to the square of the angular frequency "ω." The negative sign indicates that the acceleration is in the opposite direction of the displacement, which is a characteristic of SHM.

Q82. The difference between electsic field end magnetic field HMIS is

• A. The electric tield lines form the closed loop whereas magnetic field lines form open
• B. The magnetic field lines form the closed loop vhereas electric field lines form open✓
• C. Electric field lines contract lengthwise
• D. All of the above

Explanation: Magnetic field lines form a closed loop and electric field lines form open This is proved through ampere's circuital law which states that the closed line integral of the magnetic field (the integral of the magnetic field over a closed loop) is proportional to the current passing through the loop. In mathematical terms: ∮ B · dl = μ₀ * I 2) we know that magnetic field exists around the two poles of a magnetic whereas eclectic field can exist around unipolar charges such as single positive or negative charge which provides an open field contrary to the closed field in magnetism due to the two poles As the above explanation proved it is magnetic field that forms closed lines and not electric field hence thai option is incorrect

Q83. A car is moving along a circular path on road which has a tyres of radius 0.40m moving with a velocity of 100m/s. If the mass of the car is 2000Kg, then thky centripetal force is provided by

• A. Stearing
• B. Friction✓
• C. Engine
• D. Shafts
• E. None

Explanation: As the car moves in a circle, it needs to change its direction, which requires an inward force to counteract its natural tendency to move in a straight line (according to Newton's first law). This inward force is provided by the static or kinetic friction between the tires and the road, depending on whether the tires are sliding or not.

Q84. The SI unit of capacitance is

• A. Farad✓
• B. Ohms
• C. Volt
• D. Newton
• E. None

Explanation: Explanation is given as image.

Q85. If a body has mass In kilograms and is moving with an acceleration in meters per second squares as a result of force, the force will be in

• A. Dynes
• B. Newton✓
• C. Joules
• D. Ohms

Explanation: The force will be in newtons. The relationship between force, mass, and acceleration is given by Newton's second law of motion, which states that force equals mass times acceleration (F = ma). In the International System of Units (SI), mass is measured in kilograms (kg), acceleration is measured in meters per second squared (m/s2), and force is measured in newtons (N)

Q86. Work done on a charge equal to an electron by moving it through 1 volt is called

• A. Joules
• B. Ergs
• C. Electron Volt✓
• D. Volt

Explanation: Explanation is given as image.

Q87. The phenomenon of induced current in a coil due to change of current in another coil is called

• A. Self inductance
• B. Mutual inductance✓
• C. Induced current
• D. Motional emf

Explanation: Mutual induction is the phenomenon of inducing an electromotive force (EMF) in a coil due to the change in current in another nearby coil. When the current in one coil changes, it creates a magnetic field that interacts with the other coil, inducing a current in it

Q88. The device which converts electrical energy into mechanical energy is called

• A. Galvanometer
• B. Generator
• C. Electric motor✓
• D. Cell

Explanation: Explanation is given as image.

Q89. If the power supplied by source is 1500watt and voltage supplied is 120 volts, calculate the resistance?' How much current will flow through circuit?

• A. 9.6A, 12.5Ω
• B. 8.0A . 1.190Ω
• C. 15A : 8Ω
• D. 8A, 18.7Ω
• E. 12.5A, 9.6Ω✓

Explanation: Hence all other options are incorrect

Q90. If a lens is cut into two halves vertically, the focal length of each half will be

• A. 1/2f
• B. 2f
• C. f✓
• D. 4f
• E. None

Explanation: If a lens is cut into two halves vertically, the focal length of each half will remain the same. Cutting a lens into two pieces does not change the optical properties of each half, including its focal length. The focal length of each half will still be determined by the curvature of the lens surfaces and the refractive index of the lens material

Q91. At what angle of projection is the total energy half kinetic and halfi potential at the summit point?

• A. 45°✓
• B. 90°
• C. 30°
• D. 60°

Explanation: K.E(top)= K.E(initial)cos²θ P.E(top)=K.E( initial) sin²θ K.E(top)=K.E(i)cos45² =K.E(i)(1/√2)² =K.E(i)(½) =0.5K.E(i) P.E(top)=K.E (i)sin45² =K.E(i) (1/√2)² =K.E(i)(½) =O.5K.E(i) Hence the object will have half of its energy as K.E and half as P.E Thus (b)(c)(d) are incorrect

Q92. Radon Rn decays to Radium Ra. This is

• A. Alpha decay✓
• B. Beta decay
• C. Gamma decay
• D. Electron emission

Explanation: Radon decays to Radium" is a description of a radioactive decay process that occurs in certain isotopes of radon. Specifically, radon-222 (Rn-222), which is a radioactive isotope of radon, can decay into radium-226 (Ra-226) through a series of radioactive decay steps. This process is part of the decay chain or radioactive series known as the "radon decay chain" or "uranium-238 decay chain." Here's a simplified representation of the radioactive decay of radon-222 to radium-226: Radon-222 (Rn-222) undergoes alpha decay, emitting an alpha particle (two protons and two neutrons). Rn-222 → Ra-218 + α Radium-218 (Ra-218), which is a short-lived radon decay product, also undergoes alpha decay: Ra-218 → Rn-214 + α

Q93. A body is moving in a conservative field, which of the following statements Is true

• A. The work done is independent of path followed✓
• B. The work done is equal to the difference between final and initial energy of the body
• C. Work done can be a measured by using formula W = F.d
• D. All of the above

Explanation: It's a consequence of the properties of conservative forces and is often associated with concepts like potential energy. The work done in a conservative field is independent of the path followed because it is related to potential energy, which depends only on the positions of the object and not on the specific path taken. This principle is fundamental in understanding the behavior of objects in conservative fields, such as gravitational or electrostatic fields.

Q94. The emission of electrons from mektaltrigo incidenco of light is

• A. Photoelectric effect✓
• B. Compton effect
• C. Pair production
• D. Electron emission

Explanation: Explanation is given as image.

Q95. A wire of length "l" is suspended from a ceiling and on the other end a mass "m" is attached, the vire is under

• A. Compression Stress
• B. Shear Stress
• C. Tension✓
• D. All of the above

Explanation: When an object is suspended from a wire or a string, the wire or string experiences a force in the upward direction, which is equal in magnitude to the weight of the object. This force is called tension. In this case, the wire is under tension because it is being pulled upward by the weight of the mass attached to the other end of the wire.

Q96. If a beaker exactly filled with water and a ice piece floats on it. Which contain lead piece, when ice melts, what would occur?

• A. Level of water rises
• B. Water flows out of the beaker
• C. Level of water remains the same
• D. Level of water decreases✓

Explanation: If the ice in the space were to melt and displace less water than the volume of the space itself, the level of water in the beaker would decrease. However, since the space is already displacing its own weight in water, the amount of water in the beaker will not change when the ice melts. The lead piece will remain in the space after the ice melts. This is because the lead piece is denser than water and will sink to the bottom of the space, which is still filled with water. The level of the water in the beaker will remain the same, and the lead piece will still be in the space, but it may shift slightly due to the change in buoyancy caused by the melting of the ice.

Q97. Tvvo forces, one of magnitude 6N and other of magnitude 8N acts on a body perpendicular to each other. Find the resultant force

• A. 14N
• B. 10N✓
• C. 2N
• D. 100N

Explanation: Explanation is given as image.

Q98. Vectors

• A. Which are parallel are called equal vectors✓
• B. Which lie in same plane are called coaxial
• C. Which lie in different planes are called coplaners
• D. None

Explanation: Vectors which are parallel to each other are called equal vectors because they have the same magnitude and direction. In mathematical terms, two vectors are equal if they have the same magnitude and direction. When two vectors are parallel, it means that they have the same direction, and if they have the same magnitude as well, then they are equal vectors.

Q99. Rate of flow of charge is also called

• A. Volts
• B. Average charges
• C. Current✓
• D. Electrical intensity

Explanation: Current is the rate of flow of electric charge through a conductor. It is measured in amperes (A) and is often represented by the symbol "I"

Q100. If an object of weight 90N in air, 60N ia..water and 20N in an unknown liquid, the specific gravity of liquid is

• A. 0.3✓
• B. 1.3
• C. 2.3
• D. 4.3

Explanation: Specific Gravity = (Weight in Air) / (Loss of Weight in Water) In this case, the weight in air is 90 Newtons, and the loss of weight in water is the difference between the weight in air and the weight in water, which is 90 Newtons - 60 Newtons = 30 Newtons. So, the specific gravity of the unknown liquid is: Specific Gravity = 90 Newtons / 30 Newtons = 3 Hence all other options are incorrect