Federal Mdcat Mock Paper 3 — Solved Past Paper with Answers

Q1. Select the word with the closest meaning to the given word: Aghast

• A. Critical
• B. Reluctant
• C. Happy
• D. Horrified✓

Explanation: Aghast means to be filled with horror or shock. Hence, the closest word to it would be horrified.

Q2. Select the word with the closest meaning to the given word: Wrecked

• A. Defined
• B. Developed
• C. Ruined✓
• D. Registered

Explanation: To say something is wrecked means that it is destroyed or severely damaged. Therefore, C is the correct option.

Q3. You should stick _ your promise. Choose the best option to fill in the blank.

• A. By
• B. To✓
• C. With
• D. In

Explanation: The preposition “To” is the correct answer here as it is used as an infinitive of purpose.

Q4. The injured player was taken _ the field.

• A. Off✓
• B. Of
• C. Out
• D. In

Explanation: “Off” is used here as it shows disconnection from a person, place or object, i.e away from someone or something, in this case the field.

Q5. The box is _ green outside and white inside.

• A. Carved
• B. Created
• C. Painted✓
• D. Molded

Explanation: Since colors are referenced here, it means the correct option is “painted” as colors can only be painted onto things not carved or molded onto something.

Q6. To join the great majority means _.

• A. To accept a challenge and get ready for a fight
• B. To die✓
• C. To support the views of majority
• D. To falsify an account in order to deceive

Explanation: b) To die:This option suggests that "to join the great majority" means to pass away or die. It implies that when someone joins the great majority, they become part of the deceased population. it is a correct option.

Q7. FIND THE BEST RELATIONSHIP Breath : Lungs

• A. Light : Bulb
• B. Food : Stomach✓
• C. Blood : Vein
• D. Water : Stream

Explanation: The air we breathe goes into our lungs, just as the food we eat goes into our stomach.

Q8. Neither they nor their friend _ solved the question.

• A. has✓
• B. have
• C. was
• D. were

Explanation: The key to solving these questions is to read this sentence in your head while filling each option in the blank. Since the pronouns make the sentence singular hence, the verb should be singular

Q9. He asked me _.

• A. How are you
• B. How was I
• C. How you are
• D. How I was✓

Explanation: The key to solving these questions is to read this sentence in your head while filling each option in the blank. The confusion here is between Options A and D. ‘how I was’ fits here well and how are you would have been used if this was being written as direct speech in quotation marks.

Q10. When your friend _, he’ll be very tired.

• A. Arrived
• B. Will arrive
• C. Arrives✓
• D. Is arriving

Explanation: Future is always followed by the present. In the given sentence, in the second clause there is use of simple future so its grammatical rule that the first clause must be in simple present.

Q11. Pick up the wrong part in the sentence: The beautiful and the most attractive picture was hanged on the wall.

• A. The beautiful
• B. The most
• C. Was
• D. Hanged✓

Explanation: D is the correct option because the given sentence is in past continuous tense so hanging will be correct not was hanged. If the sentence was written in past tense then the correct word would be hung.

Q12. Pick up the wrong part in the sentence: Although I thought I had hardly left any book unread, I am surprised that I have not read these two books.

• A. I had
• B. Unread
• C. Surprised
• D. Have
• E. No error✓

Explanation: E is the correct option because the given sentence is error-free. There is the correct usage of parts of speech.

Q13. Fill in the blanks with the most appropriate option. When we went to cinema, the film _.

• A. Already started
• B. Had already started✓
• C. Would already start
• D. Started already

Explanation: The other options are wrong as 'when we went' indicates the use of the past tense. The correct answer is B) had already started.

Q14. Choose the correct spelling:

• A. Entripreneur
• B. Enterpreneur
• C. Entrepreneur✓
• D. Entreprineur

Explanation: The correct spelling is entrepreneur. It refers to a person who sets up a business or businesses, taking on financial risks in the hope of profit.

Q15. DRAWBACK, this word is a combination of:

• A. Verb + Adjective
• B. Noun + Adjective
• C. Verb + Noun
• D. Verb + Adverb✓

Explanation: Draw is a verb, while back is an adverb.

Q16. “Which is the next up train?” What does "up" represent here?

• A. Noun
• B. Verb
• C. Adverb
• D. Adjective✓

Explanation: In the context of "Which is the next up train?", "up" is an adjective. It modifies the noun "train" and indicates the direction of travel.In this specific case, "up" is an adjective used to describe the type of train, distinguishing it from a "down" train.

Q17. Demonstrate the correct use of subject-verb agreement: Plenty of mangoes and bananas _ available in this season.

• A. Is
• B. Are✓
• C. Was
• D. Were

Explanation: Since the sentence is in the present tense, ‘was’ and ‘were’ are incorrect options. The basic definition will be, that plural nouns should use plural verbs. Singular nouns, for example, apple, mango, he, she, and so on, should be having singular verbs like ‘is, has, and any verb +s. But for plural nouns like mangoes, bananas, etc, it should have plural verbs like ‘are, have’, and so on. In the given sentence, the nouns mangoes and bananas (along with the word ‘plenty’) are plurals. So the verb should be ‘are’.

Q18. The oxygen-binding protein present in skeletal muscles is:

• A. Globin
• B. Glycogen
• C. Myoglycogen
• D. Myoglobin✓

Explanation: Myoglobin is a low molecular weight oxygen-binding heme protein that is found exclusively in the heart and skeletal muscle cells.

Q19. Which of the following helps in maintaining balance?

• A. Hypothalamus
• B. Medulla Oblongata
• C. Cerebellum✓
• D. Pons

Explanation: The cerebellum is a part of the hindbrain which helps in maintaining posture and balance of the body.Hypothalamus has several endocrine functions involving thermoregulation. Pons regulate the sleep-wake cycle. Medulla Oblongata controls involuntary movements such as breathing, heart rate, etc.

Q20. Pulmonary veins supply blood to the heart chamber:

• A. Right atrium
• B. Left atrium✓
• C. Right ventricle
• D. Left ventricle

Explanation: The oxygenated blood is brought back to the heart by the pulmonary veins which enter the left atrium. From the left atrium, blood flows into the left ventricle. The left ventricle pumps the blood to the aorta which will distribute the oxygenated blood to all parts of the body.

Q21. Sensation of pleasure, punishment, or sexual arousal are stimulated by the parts of the brain:

• A. Hippocampus
• B. Hypothalamus
• C. Amygdala✓
• D. Thalamus

Explanation: The amygdala controls the sensation of pleasure, punishment, or sexual arousal.The hippocampus has a major role in learning and memory.The hypothalamus is considered to be a link structure between the nervous and the endocrine system, its main function is to maintain the homeostasis of the body.The thalamus has several functions, such as relaying of sensory signals, including motor signals to the cerebral cortex and the regulation of consciousness, sleep, and alertness.

Q22. This option is incorrect. The grana are stacks of thylakoid membranes found in the chloroplasts of plant cells. The grana are primarily involved in the light-dependent reactions of photosynthesis, where the absorption of light energy occurs.

• A. Grana
• B. Stroma✓
• C. Thylakoid
• D. Both Grana and Stroma

Explanation: The light dependent reaction takes place in the thylakoid membrane. The dark reaction(light-independent reaction) takes place in the stroma.

Q23. The word glycogenesis means, the conversion of:

• A. Glucose to glycogen✓
• B. Lactic acid to glycogen
• C. Glycogen to glucose
• D. Amino acid to glycogen

Explanation: Glycogen is the conversion of glucose to glycogen when the glucose in the body exceeds the required amount. Glycogenolysis is the biochemical pathway in which glycogen breaks down into glucose-1-phosphate and glucose. A glucogenic amino acid is an amino acid that can be converted into glucose through gluconeogenesis.

Q24. Chlorophyll molecule resembles the haem group of hemoglobin, the main difference between these two molecules is that chlorophyll has _ ion.

• A. Fe2+
• B. Mg2+✓
• C. Mn2+
• D. Ca2+

Explanation: The chlorophyll molecule consists of a central magnesium atom surrounded by a nitrogen- containing structure called a porphyrin ring; attached to the ring may be a long carbon- hydrogen side chain, referred to as a phytol chain. The heme consists of a flat organic ring surrounding an iron atom.

Q25. In many bacteria, the cell wall is enclosed within a slime capsule made up of:

• A. Polysaccharides✓
• B. Cellulose
• C. Amino acids
• D. Proteins

Explanation: The glycocalyx is an outer coating that covers the outside of the bacterial cell wall. The glycocalyx exists in two forms i.e., capsule and slime. The capsule is a condensed layer that is relatively tightly associated with the underlying cell wall and gives sticky or gummy nature to the cell, whereas, slime is a more loosely attached layer that gives slimy or slippery nature to the cell and can be removed from the cell more easily. Generally, the glycocalyx is made of polysaccharides. However, in some cases, protein can also be present.

Q26. The DNA of the bacterium is present in a distinct region called:

• A. Nucleolus
• B. Centrosome
• C. Nucleoid✓
• D. Nucleus

Explanation: Bacterial chromosomes are located in a nucleoid, a distinct cytoplasmic structure, in which double-stranded DNA is coated with histone-like proteins.

Q27. Germ Theory of disease was proposed by:

• A. Leeuwenhoek
• B. Louis Pasteur
• C. Walther Flemming
• D. Robert Koch✓
• E. Edward Jenner

Explanation: This is a fact. Robert Koch formulated the germ theory of disease.

Q28. A woman with normal colour vision, whose father was red green colour blind, married a red green colour blind man. What is the probability of her born child being red green colour blind?

• A. 1.0
• B. 0.75
• C. 0.50✓
• D. 0.25

Explanation: Males have 1 X chromosome and 1 Y chromosome, and females have 2 X chromosomes. The genes that can give you red-green colour blindness are passed down on the X chromosome.The woman’s father is red-green colour blind. Since the woman got one of her X chromosomes from her father this means that she is a carrier. As it can be seen from the table the probability of having a colourblind child is 0.5%

Q29. In aerobic respiration most of the ATP is synthesized during:

• A. Oxidation of pyruvic acid
• B. Electron transport chain✓
• C. Krebs cycle
• D. Glycolysis

Explanation: The maximum ATP yield for a molecule of glucose is around 30-32 ATP. During glycolysis, from one glucose molecule, net 2 ATP molecules are produced. During oxidation of Pyruvic acid, no ATPs are produced. During Krebs cycle, for one glucose molecule, 2 ATPs are produced. Beyond those four, the remaining ATP all come from ETC during oxidative phosphorylation. The correct answer is, therefore, B.

Q30. Number of bones in skull is:

• A. 8
• B. 14
• C. 22✓
• D. 33

Explanation: The cranium has 8 bones. 14 bones are found in the fingers of each hand and also in the toes of each foot. The spine is made up of 33 vertebrae. Vertebrae are the 33 individual bones that interlock with each other to form the spinal column. The human skull contains 22 bones. The correct answer is, therefore, C.

Q31. Gigantism in human beings is caused due to over secretion of:

• A. Thyrotropin
• B. Corticotropin
• C. Somatotropin✓
• D. Prolactin

Explanation: Gigantism occurs when a child’s pituitary gland makes too much growth hormone, which is also known as somatotropin. Corticotropin-releasing hormone (CRH), also called corticotropin-releasing factor (CRF), is a peptide hormone that activates the synthesis and release of adrenocorticotropic hormone (ACTH) from the pituitary gland. In this way, CRH affects our response to stress, addiction and depression, amongst others. Prolactin is a hormone made by the pituitary gland, a small gland at the base of the brain. Prolactin causes the breasts to grow and make milk during pregnancy and after birth. Thyroid-stimulating hormone/Thyrotropin is a hormone produced by anterior pituitary gland that stimulates the thyroid gland to produce thyroxine, and then triiodothyronine which stimulates the metabolism of almost every tissue in the body. Therefore, the correct answer is C.

Q32. The condition in which one of more genes that have no allelic counterpart is known as:

• A. Homozygous
• B. Hemizygous✓
• C. Heterozygous
• D. Incomplete dominance

Explanation: Hemizygous means having only a single copy of a gene instead of the customary two copies. All the genes on the single X chromosome in the male are hemizygous. Homozygous means having 2 identical alleles of a particular gene. Heterozygous means having 2 different alleles of a particular gene. Incomplete dominance is a form of Gene interaction in which both alleles of a gene at a locus are partially expressed, often resulting in an intermediate or different phenotype. The correct answer is, therefore, B.

Q33. Right ventricle connects with lungs by:

• A. Aorta
• B. Pulmonary veins
• C. Pulmonary artery✓
• D. Dorsal aorta

Explanation: The pulmonary artery leaves the right ventricle and takes blood to the lungs. Pulmonary vein brings blood back from the lungs to the left atrium of the heart. Aorta connects the right ventricle to pump blood to the body. The correct answer is, therefore, C.

Q34. A woman can be bald only when she is

• A. Homozygous dominant
• B. Heterozygous
• C. Homozygous recessive✓
• D. None of these

Explanation: Pattern baldness is a sex influenced trait. It is inherited as an autosomal dominant trait in males but as an autosomal recessive trait in females. A heterozygous male is bald but a heterozygous female is not. A woman can only be bald when she is homozygous recessive.

Q35. Nictitating membrane is found in the _ and performs _function.

• A. Eyes … cleaning✓
• B. Brain … thinking
• C. Feet … locomotion
• D. Bones … supporting

Explanation: The nictitating membrane is a transparent or translucent third eyelid present in some animals that can be drawn across the eye for protection and to moisten it while maintaining visibility.

Q36. Platyhelminthes means:

• A. Flat worms✓
• B. Roundworms
• C. Segmented worms
• D. None

Explanation: Word Platyhelminthes (derived from the Greek platy, meaning "flat" while helminth meaning "worm") are a phylum of relatively simple bilaterian, unsegmented, soft-bodied invertebrates.

Q37. Eukaryotic, multicellular, and consumers belong to _ kingdom.

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

Explanation: Kingdom Monera: It comprises unicellular, prokaryotic organisms, which can be heterotrophic or autotrophic, having no well-defined nucleus and no organelles. Kingdom Protista: Protists are eukaryotic, unicellular organisms They can be autotrophs or heterotrophs. Kingdom Fungi: Fungi can be single-celled or very complex multicellular organisms. All fungi are heterotrophic, which means that they get the energy they need to live from other organisms. They are eukaryotes. Kingdom Animalia: They are eukaryotic, multicellular, and heterotrophic.

Q38. Which substance might include this molecule?

• A. Cellulose
• B. Cholesterol
• C. Glycerol✓
• D. Insulin

Explanation: Glycerol has three OH groups as it forms bonds with three fatty acid molecules.

Q39. Four words are shown below:Branchioceranthus - sexual reproduction - nutritive - HydraThese words can be used in the spaces P, Q, R, and S to complete the sentence below:The coelenterates range in size from microscopic _P_ to macroscopic, _Q_, a hydrozoan polyp that may reach two meters in length. Cnidarians are found in two basic forms: the polyps and the medusae. Polyps are cylindrical animals, which in most cases are _R_ in function, hence named as gastrozooids. The medusae are umbrella-like in form. These are free-swimming. The medusae are involved in _S_ as they have gonads.

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

Explanation: Branchioceranthus is macroscopic and hydra is microscopic. P = Hydra Q =Branchioceranthus R = nutritive S= Sexual reproduction

Q40. How many fatty acid molecules are normally present in a fat or oil molecule?

• A. 1
• B. 2
• C. 3✓
• D. 4

Explanation: If we talk about a fat molecule, we are essentially discussing a lipid molecule that comprises glycerol and fatty acids linked via esterification. Since glycerol has three hydroxyl groups and a fatty acid molecule has only one carboxylic group, we need three fatty acid molecules to bind to the three hydroxyls, OH groups on the glycerol molecule.

Q41. Retrovirus cause diseases in:

• A. Rodents
• B. Fowls
• C. Cats
• D. All of these✓

Explanation: d) All of these:The correct answer is d) All of these. Retroviruses have been identified to cause diseases in rodents, fowls, and cats. These viruses can have varying effects on different species, but they are known to be pathogenic and can lead to various health issues.

Q42. What is the function of the cholesterol in a cell surface membrane?

• A. Controlling active transport
• B. Acting as a membrane blood receptor
• C. Helping cells join together
• D. Regulating the flexibility at the membrane✓

Explanation: Cholesterol helps to regulate membrane fluidity over the range of physiological temperatures. It has a hydroxyl group that interacts with the polar head groups of the membrane phospholipids and sphingolipids. Therefore, the correct answer is D.

Q43. Sperms are produced in:

• A. Urethra
• B. Sperm dust
• C. Pancreas
• D. Testes✓

Explanation: Explanation for this question will be added soon.

Q44. A muscle with characters like a spontaneous contraction, one nucleus per cell, and no control over contraction is most likely:

• A. Smooth muscle✓
• B. Cardiac muscle
• C. Skeletal muscle
• D. Visceral muscle

Explanation: Refer to the following table from Punjab Board Textbook.

Q45. Gray matter of spinal cord does not contain:

• A. Cell bodies of sensory neurons✓
• B. Cell bodies of interneurons
• C. Axons of interneurons
• D. Cell bodies of motor neurons

Explanation: Gray matter, the inner matter of the spinal cord does not contain cell bodies of sensory neurons.

Q46. Porins are present in:

• A. Mitochondria and golgi apparatus
• B. Mitochondria and chloroplast✓
• C. Mitochondria and ribosomes
• D. Golgi apparatus and chloroplast

Explanation: Porins are present in the outer membrane of mitochondria and the outer chloroplast membrane.

Q47. As the pH of the blood decreases, H+ ions increase, which combines with the protein part of hemoglobin, to decrease its ability to bind with:

• A. O2✓
• B. CO2
• C. CO
• D. H2

Explanation: The Bohr effect describes hemoglobin’s lower affinity for oxygen secondary to increases in the partial pressure of carbon dioxide and/or decreased blood pH. This lower affinity, in turn, enhances the unloading of oxygen into tissues to meet the oxygen demand of the tissue.

Q48. Apparently which bacteria is more resistant to antibiotics?

• A. Gram-positive bacteria
• B. Gram-negative bacteria✓
• C. Both Gram-negative and positive bacteria
• D. None of these options are correct

Explanation: Gram-negative bacteria have an outer layer (membrane) that protects them from their environment. These bacteria can use this membrane to selectively keep antibiotic drugs from entering. Germs get rid of antibiotics using pumps in their cell walls to remove antibiotic drugs that enter the cell. Gram-positive bacteria, those species with peptidoglycan outer layers, are easier to kill - their thick peptidoglycan layer absorbs antibiotics and cleaning products easily.

Q49. On receiving the news of the sudden demise of a close friend; which is the most probable hormone that is secreted at that time?

• A. Prostaglandin
• B. Growth inhibitors
• C. Estrogen
• D. Adrenaline✓
• E. Thyroxin

Explanation: When a close person dies, this can cause adrenal glands to pour adrenaline hormones into the bloodstream due to anxiety that subsides the emotional stress.

Q50. Which combination describes a triglyceride?

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

Explanation: Triglyceride being non-polar do not dissolve in water. They store a lot of energy in them and are hydrolysed to release water. As they are non polar they can dissolve in organic solvents.

Q51. First step of viral replication is:

• A. Entry
• B. Assembly
• C. Uncoating
• D. Adsorption or Attachment✓

Explanation: Viral infections follow similar steps in the virus replication cycle: attachment or adsorption, penetration, uncoating, replication, assembly, and release.

Q52. Vibrio cholera is an example of _ type of bacteria.

• A. Cocci
• B. Bacilli
• C. Spirilla
• D. Commas✓

Explanation: Bacteria are classified according to their shape, or morphology. Spherical bacteria are known as cocci, rod-shaped bacteria are bacilli, and spiral-shaped bacteria are spirilla, and comma shaped bacteria are known as Vibrio.

Q53. Exoskeleton of cockroach is made up of:

• A. Cartilage
• B. Cuticle
• C. Chitin✓
• D. Amino acids

Explanation: The exoskeleton of a cockroach is made up of chitin. The skeleton of a cockroach is covered by thick hard chitinous cuticles secreted by the epidermis.

Q54. The axial skeleton of an adult human includes:

• A. The skull, pectoral girdle, and ribs
• B. The skull, ribs, and bones of arms and legs
• C. The pectoral and pelvic girdles
• D. The ribs, the skull, the sternum, and the vertebrate✓

Explanation: The axial skeleton involves the ribs, skull, the sternum and the vertebrate.

Q55. Which of the following phylum and its examples is NOT correct?

• A. Nematoda… Ascaris and hookworm
• B. Annelid … Nereis and leech
• C. Echinodermata … sea star and brittle star
• D. Platyhelminthes … Planaria and liver fluke
• E. Cnidaria … Euplectella and bath sponge✓

Explanation: Euplectell and bath sponge belong to the Phylum Porifera. Examples of phylum cnidaria include Hydra, Jellyfish, and Obelia.

Q56. Which of the following produce response?

• A. Effectors✓
• B. Nerve
• C. Stimulators
• D. Brain

Explanation: Effector is a structure or organ that brings about an action of 'effect' as a result of a stimulus received through a receptor which can come from the CNS or from a hormone.

Q57. What explains the effect on a red blood cell of being placed into pure water?

• A. Less water leaves the cell than enters it, so the cell shrinks.
• B. More water enters the cell than leaves it, so the cell swells and bursts.✓
• C. Water enters the cells and none leaves it, so the cell swells and bursts.
• D. Water enters the cell and more leaves it, so the cell shrinks.

Explanation: The water potential outside is greater than the water potential inside the RBC. As a result there is net inward movement of water as water moves from high water potential to lower water potential. The correct answer is, therefore, B.

Q58. Which statement about a triglyceride molecule are correct? 1. It always contains unsaturated hydrocarbon tails 2. It is formed using ester bonds 3. It does not form hydrogen bonds 4. It contains a hydrophilic glycerol head

• A. 1, 2 and 3
• B. 2, 1 and 4
• C. 1 and 4 only
• D. 2 and 3 only✓

Explanation: Triglycerides are formed by linking fatty acids with an ester linkage to three alcohol groups in glycerol. Triglycerides are hydrophobic and so insoluble in water. The charges are evenly distributed around the molecule so hydrogen bonds to not form with water molecules. The correct answer is, therefore, D.

Q59. In term of enzyme action, maximum temperature refers to a temperature at which?

• A. Enzymes start to denature✓
• B. Enzymes start to re-nature
• C. Enzymes work best
• D. Enzymes are reactivated

Explanation: Maximum temperature refers to a temperature at which enzymes start to breakdown and denature.

Q60. The chemical which regulates the enzymatic activity is:

• A. Activator
• B. Inhibitor
• C. Substrate
• D. Both A and B✓

Explanation: Enzymes can be regulated by other molecules that either increase or reduce their activity. Molecules that increase the activity of an enzyme are called activators, while molecules that decrease the activity of an enzyme are called inhibitors.

Q61. Virus recognize host through:

• A. Envelope
• B. DNA
• C. Capsid
• D. Protein Coat✓

Explanation: A virus’ protein coat contains receptors. The virus recognizes and binds to a host cell via a receptor. The virus or its genetic material then enters the host cell. The envelope itself is derived from the host.

Q62. Cell surface markers are

• A. Lipoproteins
• B. Glycolipids
• C. Sphingolipids
• D. Glycoproteins✓

Explanation: Cell-surface markers are glycoproteins that are able to respond to or sense the environment around the cell and contain receptors that help in detection by an antibody.

Q63. Trypsinogen is activated by:

• A. Chymotrypsin
• B. Enteropeptidase✓
• C. Trypsin
• D. HCl

Explanation: Trypsinogen is activated by enterokinase, which cleaves an amino-terminal activation peptide (TAP). Hydrochloric acid (HCl), another component of the gastric juice, plays a crucial role in creating the pH required for pepsin activity.

Q64. Role of lysosomes include:

• A. Store hydrolytic enzymes
• B. Perform autophagy
• C. Destruction of cell
• D. All of above✓

Explanation: Lysosomes store hydrolytic enzymes, which play their role in autophagy and destruction of old cells. Hence, the correct option is D.

Q65. Which of the following statement is incorrect:

• A. Photoelectric emission does not occur below the threshold frequency
• B. The photoelectric current increases with the frequency of incident light✓
• C. Threshold frequency depends on the metal used
• D. The emission of photoelectrons is an instantaneous process

Explanation: In photoelectric effect Electrons are emitted instantaneously; the intensity of light determines only their numbers. So, photoelectric current is independent on the frequency of light.

Q66. The haploid number of chromosomes in human beings:

• A. 4
• B. 10
• C. 24
• D. 23✓

Explanation: Humans contain 46 chromosomes in their cells, this number is diploid. The haploid number is half of the diploid number which is 23.

Q67. Rod-shaped bacteria are known as:

• A. Cocci
• B. Bacilli✓
• C. Spirilla
• D. None of these

Explanation: Bacteria are classified according to their shape, or morphology. Spherical bacteria are known as cocci, rod-shaped bacteria are bacilli, and spiral-shaped bacteria are spirilla.

Q68. Which of the following correctly shows structures which are found in a eukaryotic cell? (Yes present; No = absent)

• A. No No No
• B. No Yes No
• C. Yes No No
• D. Yes No Yes
• E. Yes Yes Yes✓

Explanation: Each eukaryotic cell has a plasma membrane, cytoplasm, a nucleus, ribosomes and mitochondria. The genetic material is present within the nucleus which is surrounded by nuclear membrane/nuclear envelope .

Q69. The RNA found in Ribosomes is:

• A. mRNA
• B. rRNA✓
• C. tRNA
• D. Polysome
• E. Genes

Explanation: Ribosomal RNA (rRNA) is the most abundant type of RNA in cells. It is found in ribosomes, which are the cellular structures that are responsible for protein synthesis. rRNA makes up about 80% of the mass of ribosomes. They are made up of two subunits, a large subunit and a small subunit. Both subunits contain rRNA, as well as a number of proteins. It is involved in the assembly of ribosomes and in the translation of mRNA into proteins.

Q70. In humans,_ is responsible for producing cell's hydrogen peroxide.

• A. Lysosomes
• B. Mitochondria
• C. Peroxisomes✓
• D. glyoxysome

Explanation: The main chemical produced by oxidation in peroxisomes is the very cytotoxic (cell toxic) hydrogen peroxide. Fortunately peroxisomes produce copious amounts of the enzyme catalase and this helps break down hydrogen peroxide to water and oxygen.

Q71. HIV-I protease is an enzyme produced by the HIV virus. Two identical chains of 99 amino acids form the enzyme. In each chain, amino acids 25, 25 and 27 in the sequence form part of the active site. Which orders of protein structure control the shape of the active site?

• A. Primary, secondary, tertiary and quaternary
• B. Primary, secondary and tertiary only
• C. Primary and quaternary only
• D. Quaternary only✓

Explanation: Specific amino acids are required in the active site to bind to the substrate. The shape of the active site is essential for substrate binding, and this depends on the first three levels of structure. In a multi-subunit enzyme, the quaternary structure may also be involved.

Q72. The reflex arc, which is made of two neurons is known as:

• A. Monosynaptic reflex arc✓
• B. Disynaptic reflex arc
• C. Polysynaptic reflex arc
• D. Asynaptic reflex arc

Explanation: Monosynaptic reflex arc has only two neurons, i.e. sensory and motor which form one synapse. Depending upon the number of synapses, reflexes are categorised as monosynaptic, disynaptic and polysynaptic ones. The reflex arc with single synapse and therefore, only 2 neurons (afferent and efferent neurons) is called monosynaptic. For example, stretch reflexes. Disynaptic arcs have one interneuron located between afferent and efferent neurons of the reflex arc i.e., they have two synapses and three neurons which makes option B incorrect. For example, inverse stretch arc. Polysynaptic reflexes are characterised by the presence of more than one interneuron between afferent and efferent neurons of the reflex arc i.e, more than three neurons which makes option C incorrect. For example, cross flexor reflex, withdrawal reflex etc. Option D is incorrect as reflex arc has at least one synapse and two neurons.

Q73. Cell membrane of bacterial cell invaginates producing structure called:

• A. Polysome
• B. Endosome
• C. Mesosome✓
• D. Centrosome

Explanation: Mesosome is a convoluted membranous structure formed in a prokaryotic cell by the invagination of the plasma membrane. Polysomes are aggregates of numerous ribosomes that are in the process of actively translating mRNA into protein. Endosomes are membrane-bound vesicles, formed via a complex family of processes collectively known as endocytosis, and found in the cytoplasm of virtually every animal cell. The correct answer is, therefore, C.

Q74. The life span of RBC is:

• A. 100 days
• B. 110 days
• C. 120 days✓
• D. 130 days

Explanation: This is a standard answer. Lifespan of RBCs is approximately 120 days.

Q75. What describes a non-specific immune response?

• A. Activation of killer T lymphocytes by infected cells
• B. Cloning of B lymphocytes to form plasma cells
• C. Ingestion of a bacterial cell by a neutrophil✓
• D. Presentation of antigen on the cell surface of macrophages

Explanation: c) Ingestion of a bacterial cell by a neutrophil:This option describes a non-specific immune response. Neutrophils are a type of white blood cell and part of the innate immune system. They are capable of engulfing and destroying pathogens, such as bacteria, through a process called phagocytosis. This is a non-specific response as neutrophils can target a wide range of pathogens without requiring prior exposure.

Q76. Which of the following is found at the end of long bones, in the nose, larynx, and trachea?

• A. Elastic cartilage
• B. Fibrous cartilage
• C. Perichondrium
• D. Hyaline cartilage✓

Explanation: Hyaline cartilage is the most abundant type of cartilage and is found in the nose, ears, trachea, larynx, and smaller respiratory tubes. Fibrocartilage is found in vertebral discs and ligaments. Elastic cartilage is found in the external ear and epiglottis.

Q77. At temperature higher than optimum, enzymatic activity decreases because of:

• A. Saturation
• B. Inhibition
• C. Denaturation✓
• D. Composition

Explanation: Enzymes are protein in nature. At a temperature higher than optimum temperature, the 3D shape of active site denatures and substrate molecules can no longer fit into it. This is termed as denaturation of enzymes.

Q78. In bacteria, the resistance against heat is provided by:

• A. Granules
• B. Cysts
• C. Spores✓
• D. Plasmids

Explanation: Spores are thick, dormant, and tough structures produced by some bacteria that provide resistance or protection against harsh or adverse conditions.They are formed by the bacteria to protect themselves from adverse environmental conditions such as heat, UV rays, nutrient deprivation, presence of toxic chemicals, etc.

Q79. These hormones perform antagonistic function EXCEPT:

• A. Growth Hormone – Somatostatin
• B. Calcitonin – Parathyroid
• C. Adrenaline – Noradrenaline✓
• D. Insulin – Glucagon

Explanation: A is incorrect because somatostatin inhibits the release of growth hormone from the pituitary gland. B is incorrect because calcitonin decreases blood Ca2+ levels while parathormone increases blood calcium levels. D is incorrect because insulin decreased blood glucose concentration and glucagon raises blood glucose concentration. Adrenaline and noradrenaline are both involved in the fight or flight response during times of emergency. Hence, they are not antagonistic.

Q80. It is the smallest eukaryote:

• A. Virus
• B. Bacteria
• C. Plasmodium✓
• D. Sponge

Explanation: Plasmodium belongs to the kingdom Protozoa which are Eukaryotes and are microscopic. Viruses' classification to even living things is in debate. Bacteria are prokaryotes. Sponges are found underwater and are visible by the naked eye.

Q81. Hormones called gonadotropins are released by which gland?

• A. Ovaries
• B. Hypothalamus
• C. Pituitary✓
• D. Testes

Explanation: Gonadotropins are released by the pituitary gland. Examples include LH, FSH etc.

Q82. Which of the following ideas was not part of Charles Darwin’s theory of evolution by natural selection?

• A. Organisms produce more off springs than the environment can support
• B. Variation between individuals arises by gene mutation✓
• C. Only those individuals best adapted by environment survive and reproduce
• D. Individuals compete for scarce resources

Explanation: The idea that was not part of Charles Darwin's theory of evolution by natural selection is Option B: Variation between individuals arises by gene mutation. While Darwin acknowledged the existence of variation, he did not have a detailed understanding of the genetic mechanisms behind it, such as gene mutations.

Q83. Evolution of kiwi, food of modern horse, webbed feet of duck, and loss of teeth in whale were all explained in detail by:

• A. Lamarck✓
• B. Darwin
• C. Weismann
• D. De Vries

Explanation: Lamarckism is a theory of evolution based on the principle that physical changes in organisms during their lifetime. Examples include evolution of kiwi, foot of modern horse, webbed feet of duck, and loss of teeth in whale.

Q84. Which of the following is NOT TRUE about interferons?

• A. Belong to cytokines
• B. Activate natural killer cells
• C. Activate immune cells
• D. Secrete interleukin✓

Explanation: Interferons (IFNs) are a broad class of cytokines that are part of your natural defenses. They tell your immune system that germs or cancer cells are in your body. And they trigger killer immune cells to fight those invaders. Interferons got their name because they "interfere" with viruses and keep them from multiplying.

Q85. Intrinsic factor secreted by parietal cells of stomach mucosa helps in:

• A. Vitamin B12 absorption✓
• B. Protein digestion
• C. Carbohydrate breakdown
• D. Bowel movement

Explanation: Intrinsic factor plays a crucial role in the transportation and absorption of the vital micronutrient vitamin B12.

Q86. Identify the correct statement:

• A. Element sodium can be prepared and isolated by electrolyzing an aqueous solution of NaCl
• B. Elemental Na is a strong oxidizing agent
• C. Elemental Na is insoluble in NH3
• D. Elemental Na is easily oxidizing✓

Explanation: Good reducing agents include the active metals, such as sodium, magnesium, aluminum, and zinc, which have relatively small ionization energies and low electro-negativities.

Q87. Which of the following statements is true?

• A. Alkali metal hydroxides are stable to heat except LiOH✓
• B. CaOH is a stronger base than NaOH
• C. When NaOH is made the gas released at the cathode is C12
• D. NaOH is named as caustic soda because it reacts with fats to form soap.

Explanation: The normal alkali metal oxides react with water to form hydroxide. The hydroxide (MOH) are colorless, strong alkaline and corrosive compounds. These are soluble in water and dissolve with the evolution of heat. All alkali metal hydroxides are thermally stable except LiOH. On heating, Lithium hydroxide decomposes to form lithium oxide. 2LiOH → Li2​O+H2​O

Q88. The substance which conducts electricity by the movement of ions:

• A. Graphite
• B. Copper
• C. Molten NaCl✓
• D. Mercury

Explanation: Carbon atom has 4 electrons in its outer shell. This delocalised electron can move move freely between the carbon layers of graphite and conduct electricity. However, in the solid state, ionic compounds such as sodium chloride have their ions fixed in position and therefore these ions cannot move so solid ionic compounds cannot conduct electricity. However in the molten state, ions in ionic compounds are free to flow and therefore molten sodium chloride can conduct electricity.

Q89. Which class of the compounds is represented by the type formula ROR?

• A. Esters
• B. Ethers✓
• C. Aldehydes
• D. Ketones

Explanation: Ethers functional group is an oxygen atom singly bonded to two alkyl or aryl groups or chains R-O-R.

Q90. Formalin is an aqueous solution of:

• A. Formic acid
• B. Formaldehyde✓
• C. Furfuraldehyde
• D. Acetone

Explanation: Formalin is a water-based saturated solution of formaldehyde gas. It contains about 40% formaldehyde gas. The rest of the options are incorrect as these substances are not found in formalin.

Q91. If a molecule MX3 has zero dipole moment, the sigma bonding orbitals used by M are:

• A. Pure p
• B. sp hybrids
• C. sp2 hybrids✓
• D. sp3 hybrids

Explanation: In order for MX3 molecule to have zero dipole moment, it must have a symmetrical shape which in this case can only be trigonal planar. The bond angle in this case between X-X would be 120o so it should have sp2 hybrids.

Q92. On hydrogen atom spectrum, series of spectral lines which fall within visible region, is:

• A. Lymen series
• B. Balmer Series✓
• C. Paschen series
• D. Bracket series
• E. Pfund series

Explanation: Lyman series of hydrogen atom lies in ultraviolet region, Balmer series lies in visible region while Pfund and Paschen series lie in infrared region.

Q93. The second and third period contain:

• A. 18 elements each
• B. 32 elements each
• C. 8 elements each✓
• D. 14 elements each

Explanation: Fact.The 2nd-period elements: lithium, beryllium, boron, carbon, nitrogen, oxygen, fluorine, and neon. The 3rd-period elements: sodium, magnesium, aluminum, silicon, phosphorus, sulfur, chlorine, and argon.

Q94. Element X is in group 3 and element Y is in group 6 of the periodic Table. Which of the following is the most likely formula of the compound formed when X and Y react together?

• A. X3Y2
• B. X3Y6
• C. X2Y3✓
• D. None of these

Explanation: Element X will have a valency of +3 while Y will have a valency of -2. Thus the most likely formula of the compound is X2Y3.

Q95. For which equilibrium does Kc has no unit?

• A. C(s) + H2O(g) -> CO(g) +2H2(g)
• B. CH3O(l) + CH3CO2H(l) -> CH2CO2CH2(l) + H2O (l)✓
• C. Cu2+(aq) + 4NH2(aq) -> Cu(NH2)23+ (aq)
• D. N2O4(g) -> 2NO2

Explanation: The units of Kc are dependent upon the number of moles of (only of gases and liquids, not solids like in option A) reactants and products. If the number of reactants and products becomes equal, Kc will have no unit. For the reaction;CH3OH + CH3CO2H ==> CH₂CO₂CH₂+ H₂OThe number of moles of the reactants and products is the same, i.e. 2, thus Kc has no unit.

Q96. Which class of halogenoalkane can react with alkali by an SN2 mechanism?

• A. Primary and secondary✓
• B. Secondary and tertiary
• C. Primary and tertiary
• D. Primary, secondary and tertiary

Explanation: a) Primary and secondary:This option suggests that both primary and secondary halogenoalkanes can react with alkali by an SN2 (substitution nucleophilic bimolecular) mechanism. In SN2 reactions, the nucleophile attacks the carbon atom bearing the leaving group, resulting in a simultaneous substitution of the leaving group and the nucleophile. Primary and secondary halogenoalkanes are suitable for SN2 reactions because they have a less hindered carbon center, allowing the nucleophile to approach and substitute the leaving group more easily.

Q97. Which compound is most ionic?

• A. Li2O
• B. MgO
• C. AlF
• D. NaF✓

Explanation: Fluorine has a high negativity of 3.98, while Na has an electronegativity of Na is 0.93. For a compound to be ionic, the E.N difference must be greater than 2.1. 3.98 – 0.93 = 3.05 > 2.1, meaning that NaF is highly electronegative.

Q98. Which of the following represents the equation for the reaction between ethane and chlorine in the presence of UV radiation?

• A. C2H4 + Cl2 -> C2H2Cl2 + H2
• B. C2H4 + Cl2 -> C2H3Cl + HCl✓
• C. C2H4 + Cl2 -> 2CH3Cl
• D. C2H4 + O2 -> 2CH2Cl + 2HCl

Explanation: The question will be explained later

Q99. The number of nitrogen atoms present in 160 amu of ammonium nitrate are:

• A. 4✓
• B. 5
• C. 6
• D. 8

Explanation: 1 molecule of NH4NO3 = 80 amu As 2 times 80 is 160, therefore by balanced chemical equation, 160 amu of NH4 are present in two molecules. 80 amu : 1 molecule 80 × 2 amu : 2 molecules 160 amu : 2 molecules

Q100. Which increases down the group for alkali metals?

• A. Electron affinity
• B. Reactivity✓
• C. Ionisation energy
• D. All of the above options are correct

Explanation: The reactivity of Group I elements increases as you go down the group because: the atoms get larger as you go down the group. the outer electron gets further from the nucleus as you go down the group.

Q101. Electron affinity decreases down the group due to:

• A. Increase in atomic radius✓
• B. Decrease in atomic radius
• C. Increase in electronegativity
• D. All of the above options are correct

Explanation: Electron affinity decreases from top to bottom within a group. This is caused by the increase in atomic radius.

Q102. It is impossible for two electrons to have same value of spin quantum number in the same orbital, according to:

• A. Hund’s rule
• B. Aufbau principle
• C. Pauli’s exclusion principle✓
• D. All of the above options are correct

Explanation: The Pauli Exclusion Principle states that, in an atom or molecule, no two electrons can have the same four electronic quantum numbers. As an orbital can contain a maximum of only two electrons, the two electrons must have opposing spins.

Q103. Diamond is:

• A. Covalent solid✓
• B. Molecular solid
• C. Metallic solid
• D. Ionic solid

Explanation: Diamond is a network covalent solid.

Q104. Ideal gas equation is:

• A. P = nRT
• B. PV = RT
• C. V = nRTP
• D. PV = nRT✓

Explanation: According to the Ideal Gas equation: The product of Pressure & Volume of a gas bears a constant relation with the product of Universal gas constant, number of moles of gas and temperature. ie. PV = nRT.

Q105. How many moles of CO2 contain 16g of oxygen?

• A. 5 mol
• B. 16 mol
• C. 0.5 mol✓
• D. 2 mol

Explanation: 1 mol of CO2 contains = 32 g O2=1 6 g O2 will be present in = 16/32 = 0.5 mol

Q106. The maximum density of water is at:

• A. 2.98˚C
• B. 3.98 ˚C
• C. 4 ˚C✓
• D. 4.98 ˚C

Explanation: The maximum density of water is at 4°C as there are two opposite effects that are in balance. The density of ice is less than liquid water, so it floats. Upon freezing, the ice density decreases by about 9%.

Q107. Homocyclic hydrocarbons are further divided into:

• A. Alicyclic and aromatic✓
• B. Carbocyclic and heterocyclic
• C. Acyclic and heterocyclic
• D. Heterocyclic and aromatic

Explanation: Homocyclic compounds are divided into two compounds. Alicyclic compounds and aromatic compounds.

Q108. Which contains sp2 hybridization?

• A. Methane
• B. Ethane
• C. Alkyne
• D. None of these options are correct✓

Explanation: The hybridization of methane molecules occurs by mixing one orbital with three p orbitals. In ethane (CH3CH3), both carbons are sp3-hybridised. Alkynes undergo sp hybridization.

Q109. Diameter of an atom is in the range of?

• A. 0.2m
• B. 0.2 nm✓
• C. 2 x 10^-19nm
• D. 0.2 pm

Explanation: The diameter of an atom ranges from about 0.1 to 0.5 nanometer."

Q110. 78 g of a hydrocarbon occupies 22.414 dm3 of volume at S.T.P. The empirical formula of the hydrocarbon is CH. The molecular formula of this hydrocarbon is:

• A. C2H4
• B. C6H6✓
• C. C8H8
• D. C4H4

Explanation: Molar mass of CH =12+1 = 13gMolar mass of the hydrocarbon = 78g as 22.414dm3 is equal to 1 mol.Molecular formula = n * Empirical formula78 = n * 13n = 6So the molecular formula is 6(CH) = C6H6 i.e. option B.

Q111. Point out the property which is not characteristic of alkali metal:

• A. Low electronegativity
• B. Low melting point
• C. Their ions are isoelectronic with noble gas
• D. High ionization energy✓

Explanation: Alkali metals have low ionization energies due to their larger atomic radii.

Q112. Metals belonging to the same group in the periodic table are:

• A. Magnesium and Sodium
• B. Magnesium and Copper
• C. Magnesium and Barium✓
• D. Magnesium and Potassium

Explanation: Refer to the image below. As we can see in the periodic table, Magnesium and Barium are the only two metals from the options which are in the same group (Group II).

Q113. Magnesiums keep on burning in:

• A. CO2✓
• B. Magnesium and Copper
• C. N2O
• D. N2 as well as CO2

Explanation: When burning magnesium is placed in carbon dioxide it keeps burning with a bright flame.

Q114. Example of nucleophile is:

• A. BF3
• B. SO3
• C. AlCl3
• D. CN✓

Explanation: Nucleophiles are the elements/compounds containing extra pairs of electrons. CN is the only compound having extra pair of electron in the list above.

Q115. In the electrolysis of molten ZnCl2 , how much Zn can be deposited at the cathode by the passage of 0.01 ampere for one hour?

• A. 0.002 g
• B. 0.123 g
• C. 0.012 g✓
• D. 0.004 g

Explanation: In this scenario, we first find the total number of charges flown through the apparatus. The formula that we are going to be using is Charge= Ampere x Time. 1 mole of Zn is formed when we have two moles of electrons being added to 1 mole of Zn2+. 1 mole of electrons carries a charge of 96500 coulombs. So, 2 moles of electrons would have a charge of 193000C. To find the moles of Zn deposited, we have the charge passed divided by the charge required to form 1 mole of Zn. Once we have the moles, we multiply them by the molar mass. For a better understanding, please see the attached solution.

Q116. Oxidation of primary alcohol gives:

• A. Ketone
• B. Aldehyde✓
• C. Ester
• D. Amide

Explanation: Oxidation of primary alcohol leads to the formation of aldehyde.

Q117. 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.

Q118. A carbonyl compound with molecular formula C5H10O reacted with iodine in an alkaline solution to give a pale yellow precipitate with an antiseptic smell. The carbonyl compound is:

• A. CH3CH2CH3CH3CHO
• B. CH3CH2CH2COCH3✓
• C. CH3CH2CH(CH3)CHO
• D. CH3CH2COCH2CH3

Explanation: This is the iodoform reaction. It is given by methyl ketones or alcohols containing -CH(OH)CH3. One look at the options shows that there are no alcohols. Thus we need to look for a compound containing the methyl ketone group (-COCH3). This is found in option B.

Q119. The shape of sulphate ion is:

• A. Hexagonal
• B. Square planar
• C. Trigonal bipyramidal
• D. Tetrahedral✓

Explanation: The structure of Sulphate ion is tetrahedral, as given below;

Q120. How many chain isomer can be obtained from alkane C6H14 :

• A. 7
• B. 6
• C. 5✓
• D. 4

Explanation: Hexane (C6H14) has five possible isomers. The isomers are as follows;- Hexane, CH3CH2CH2CH2CH2CH3, a six carbon containing, saturated straight chain alkane. - 2-Methylpentane (Isohexane), CH3CH(CH3)CH2CH2CH3, which is a five carbon containing chain with one methyl branch on the carbon number 2.- 3-Methylpentane, CH3CH2CH(CH2)CH2CH3, is also a five-carbon chain, however the methyl group is attached on Carbon number 3.- 2,3-Dimethylbutane, CH3CH(CH3)CH(CH3)CH3, is a four-carbon -containing chain with a methyl group on carbon number 2 and 3.- 2,2-Dimethylbutane (neohexane), CH3C(CH3)2CH2CH3, is a four-carbon chain with two methyl groups attached on carbon number two.

Q121. The oxidation number of iodine is periodic acid (H5IO6) is:

• A. +7✓
• B. +3
• C. +6
• D. +5

Explanation: a) +7:The oxidation number of iodine in periodic acid (H5IO6) is indeed +7. In periodic acid, iodine is in its highest possible oxidation state. Each oxygen atom in the IO6 group carries an oxidation number of -2, and since the overall charge of the periodic acid molecule is 0, the oxidation number of iodine must be +7 to balance out the negative charges. Explanation:

Q122. Which quantum number tells shape of the orbital?

• A. Magnetic quantum number
• B. Spin quantum number
• C. Azimuthal quantum number✓
• D. Principle quantum number

Explanation: The Azimuthal quantum number (l) describes the shape of the orbital.

Q123. The number of electrons in the p subshell is:

• A. 2
• B. 14
• C. 10
• D. 6✓

Explanation: p subshell has 3 orbit and 1 orbit has maximum 2 electrons.

Q124. Which one of the following has greater bond energy?

• A. HF✓
• B. HCl
• C. HBr
• D. HI

Explanation: HF has greater bond energy than HCl. The bond energy of HF is 568 kJ/moL, while the bond energy of HCl is 431 kJ/moL.

Q125. Oxidation number of an element in free state is:

• A. +1
• B. +2
• C. 0✓
• D. -1

Explanation: Free state means uncombined state, i.e., atomic state. In an uncombined state the oxidation number will always be zero.

Q126. A piston in a cylinder is a part of:

• A. System
• B. Surroundings✓
• C. Boundary
• D. None of these options are correct

Explanation: The substance within the cylinder is the system and cylinder itself, piston and everything outside the cylinder is a part of the surrounding.

Q127. Fossil fuels are produced due to _ ?

• A. Fast decomposition of organic matter
• B. Decomposition of plants
• C. Decomposition of animals
• D. Biochemical decomposition of dead organic matter✓

Explanation: We obtain fossil fuels from the decomposition (decay) of organic matter (plants and animals).

Q128. The current in electrolysis is carried through:

• A. Free electrons
• B. Positive ions
• C. Negative ions
• D. Both Options B and C are correct✓

Explanation: In electrolysis, current is carried through the electrolytic solution inside the cell by positive and negative ions using oxidation-reduction reactions. The liquid will continue to conduct electricity only as long as oxidation-reduction reactions occurring at the electrodes continue.

Q129. BH3 has H-B-H bond angles of 120˚ with a shape of:

• A. Linear
• B. Trigonal planar✓
• C. Tetrahedron
• D. Bent

Explanation: BH3 is an AB3 type molecule with no lone pair. So, it has trigonal planar geometry and each angle is of 120°.

Q130. Addition of a second electron to a uni-negative ion is always _?

• A. An endothermic process✓
• B. An exothermic process
• C. Neutral process
• D. Energy wasted

Explanation: When a second electron is added to a uni-negative ion, the incoming electron is repelled by the already present negative charge, and energy is absorbed in this process. It is an endothermic process and the absorbed energy is given a positive sign. So, electron affinity is positive.O + e- → O1- EA1 = -141 kJ/molO- + e- → O2- EA2 = +744 kJ/mol.

Q131. [Fe(CN)6]4- is called as _?

• A. Complex compound
• B. Transition element ion
• C. Anion
• D. Complex anion✓

Explanation: K4[Fe(CN)6] is a complex compound. On ionization, it gives 4K+ and [Fe(CN)6]4-. Here, 4K+ is a complex cation and [Fe(CN)6]4- is a complex anion.

Q132. Which one of the following is not a secondary alkyl halide?

• A. 2-Chloropropane
• B. 3-Bromobutane
• C. 2,3-Dichloropentane
• D. 2-Chloro-2-methylpentane✓

Explanation: In this compound, the carbon atom bonded to chlorine is attached to only one other carbon atom (the methyl group). Therefore, it is not a secondary alkyl halide. Therefore, option d is correct.

Q133. The strength of London forces depends on the size of:

• A. Electrons.
• B. Electronic cloud.✓
• C. Lone pair on an atom.
• D. Poles of atoms

Explanation: The strength of London forces depends upon the size of the electronic cloud of the atom or molecules. When the size of the atom or molecule is big then the dispersion becomes easy and these forces end up being more prominent.

Q134. The evaporation of water is an example of?

• A. Endothermic reaction✓
• B. Exothermic reaction
• C. Spontaneous reaction
• D. Chemical reaction

Explanation: Evaporation of water is an endothermic reaction. During evaporation, water molecules absorb heat from the surroundings and change into vapours and evaporate. That's why the surroundings become cool.

Q135. Why does Cr show 3d54s1 configuration instead of 3d44s2?

• A. Because it is transition element
• B. Because it shows different oxidation states
• C. Because of extra stability of half filled d5 system✓
• D. Because it is typical transition element

Explanation: The correct answer is: Because of the extra stability of the half-filled d5 system. The electron configuration of chromium (Cr) is often represented as 3d5, 4s1 instead of 3d4, 4s2. This is because the configuration of 3d5, 4s1 provides a half-filled d-orbital, which offers extra stability compared to the 3d4, 4s2 configuration.

Q136. If the temperature of reaction medium increases above the optimum temperature, then _?

• A. It increases the enzyme activity
• B. Stops the reaction
• C. Decreases the enzyme activity
• D. Both Options B and C are correct✓

Explanation: is temperature of a reaction medium increases above the optimum temperature then it stops reaction by decreasing enzyme activity because enzymes are temperature specific.

Q137. Which of the following gives a free radical reaction when it reacts with alkanes?

• A. Nitric acid
• B. Oxygen
• C. Halogen✓
• D. All of these options are correct

Explanation: When halogens react with alkanes, the reaction is a free radical reaction. The reaction involves three steps: initiation, propagation, and termination.

Q138. A peptide having up to 10,000 amino acids is called as _ ?

• A. Dipeptide
• B. Protein✓
• C. Polypeptide
• D. Peptide

Explanation: Relatively shorter peptides are known as oligopeptides whereas longer polymers are called polypeptides. Polypeptides containing more than 100 amino acids having molecular mass higher than 10,000 are generally called as proteins.

Q139. Carboxylic acids are produced by the oxidation of _?

• A. Alcohol
• B. Aldehyde
• C. Ketone
• D. All of these options are correct✓

Explanation: We can get carboxylic acids by the oxidation of alcohols, aldehydes, and ketones as follows: R-CH2-OH + O2 → K2Cr2O2, H2SO4 → RCOOH R-CHO + O → K2Cr2O7, H2SO4 → RCOOH CH3-CO-CH3 + 3[O] → K2Cr2O7, H2SO4→ CH3COOH + HCOOH

Q140. A bar magnet has a magnetic moment 200 Am2. The magnet is suspended in a magnetic field of 0.30 NA-1m-1. The torque required to rotate the magnet from its equilibrium position at an angle of 30˚ will be:

• A. 30Nm✓
• B. 3073 Nm
• C. 60Nm
• D. 604Nm

Explanation: τ = MBsinθTorque = 200×0.30×sin30 = 30 Nm.

Q141. A ball is thrown vertically upward with a velocity of 98 m/s. If it takes 10 seconds to reach the highest point then the acceleration of the ball is:

• A. 9.8m/s2
• B. 98m/s2
• C. 980m/s2
• D. -9.8m/s2✓

Explanation: a = (Vf -Vi)/ ta = 0 - 98 / 10 = -9.8 m/s2.

Q142. The velocity of a car traveling on a straight road is 36 km/h at an instant of time. Now traveling with uniform acceleration for 10s. The velocity becomes exactly double if the wheel radius of the car is 25cm then which of the following numbers is the closest to the number of revolutions that the wheel makes during these 10s?

• A. 84
• B. 95✓
• C. 126
• D. 135

Explanation: This is the following question:

Q143. 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.

Q144. A wire of initial length L and radius r is stretched by a length I. Another wire of the same material but with an initial length of 2L and radius 2r is stretched by length 2l. The ratio of the stored elastic energy per unit volume in the first and second wire is:

• A. 1:4
• B. 1:2
• C. 2:1
• D. 1:1✓

Explanation: This is the following solution:

Q145. A wire carries a current out of the page. Which diagram below correctly describes the magnetic field of the wire?

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

Explanation: The magnetic field lines form concentric circles around the wire. If you wrap your right hand’s fingers around the wire with your thumb pointing in the direction of the current, then the direction in which the fingers curl will give the direction of the magnetic field. As the current is directed out of the page, then the magnetic field will have a counter clockwise direction. So “D” is the correct answer.

Q146. If an ideal gas has volume V at 27°C and it is heated at constant pressure so that it volume become 1.5V, the value of final temperature is:

• A. 327K
• B. 871K
• C. 177°C✓
• D. 600°C

Explanation: According to Charles Law, V1/T1 = V2/T2(Note: For these questions, always make sure the temperature is in Kelvin)Initial temperature = 27°C For converting temperature in Celcius to Kelvin:273+27 = 300KV/300 = 1.5V/T2T2= (1.5V x 300)/VT2=450KFor converting temperature in Kelvin to Celcius:450-273 = 177°C

Q147. Two capacitors C1 (6µF) and C2 (12µF) are in series across a 180 volts D.C supply. Calculate the charges on C1 and C2 respectively.

• A. 120x106 C, -420x106 C
• B. 320x10-6 C, 420x10-6 C
• C. 420x10-6 C, 320x10-6 C
• D. 720x10-6 C, 720x10-6 C✓
• E. 620x10-6 C, 420x10-6 C

Explanation: Charge remains same in series and charges of both capacitors are only same in Option D and so it is the right answer. You can even calculate the charge using this; net capacitance in series: 1/C= 1/C1 + 1/C2 1/C = 1/12 + 1/6 C= 4x10-6 F C=Q/V 4x10-6 = Q/180 Q= 720 x 10-6 C

Q148. A motorist travelling at 10 ms^-1 can bring his car to rest in a braking distance of 10 m. In what distance could he bring the car to rest from the period of 30 ms^-1 using the same breaking force?

• A. 17m
• B. 30 m
• C. 52 m
• D. 90 m✓

Explanation: Initial velocity = u = 10 m/s Final velocity = v = 0 m/s Distance covered = 10 m Acceleration of the bike, 2as = v2-u2 2(a)(10) = (0)2-(10)2 20 a = -100 a = -100/20 a = -5 m/s2 Therefore in the next condition, initial velocity =u = 30 m/s final velocity =v = 0 m/s acceleration = -5 m/s^2 ( as deduced ) therefore distance travelled by the bike, 2as = v2-u2 2(-5)(s) = (0)2-(30)2 -10 s = -900 s = -900/-10 s = 90 m.

Q149. The range of the projectile when launched at an angle of 15 degrees with the horizontal is 15 m. Its range, when launched at 45 degrees with the same speed is:

• A. 30.0 m✓
• B. 1.5 m
• C. 6.0 km
• D. 0.752 km

Explanation: The explanation is given below.

Q150. What is the internal energy of an object?

• A. It is the energy associated with the object's movement through space.
• B. It is the sum of all the microscopic potential and kinetic energies of the molecules✓
• C. It is the energy due to attractions between the molecules within the object.
• D. It is the energy associated with the random movement of the molecules in the object.

Explanation: Internal energy includes energy on a microscopic scale. It is the sum of all the microscopic energies such as: translational kinetic energy, vibrational and rotational kinetic energy, and potential energy from intermolecular forces.

Q151. What is a typical value for the order of magnitude of the resistivity of copper?

• A. 10^-8 Ωm✓
• B. 10^-10 Ωm
• C. 10^-6 Ωm
• D. 10^2 Ωm

Explanation: The resistivity of copper is generally given as: 1.72 x 10^-8 Ωm. The resistivity of a particular material is measured in units of Ohm-Metres (Ωm) which is also affected by temperature.

Q152. The average translational kinetic energy for molecule of an ideal gas is given by:

• A. A✓
• B. B
• C. C
• D. D

Explanation: The average translational energy of a molecule is given by the equipartition theorem as, E=3kT2 where k is the Boltzmann constant and T is the absolute temperature.

Q153. Instantaneous acceleration of system executing SHM is directed:

• A. Towards the mean position✓
• B. Away from the mean position
• C. Perpendicular to the mean position upward
• D. Perpendicular to the mean position downward

Explanation: As the acceleration in SHM is always in the opposite phase to that of displacement. The displacement of the particle in SHM at an instant is directed away from the mean position. Then acceleration at that instant is directed towards the mean position.

Q154. If the mass of the bob of simple pendulum is doubled, its time period is:

• A. One half
• B. Doubled
• C. Remains constant✓
• D. One fourth

Explanation: Time period of a simple pendulum is given by T=1/2π √ (l/g). This means that the time period of a pendulum does not depend on the mass of the bob. So, if the mass of the bob doubled, the time period remains the same.

Q155. The time rate of change of velocity is called:

• A. Force
• B. Acceleration✓
• C. Power
• D. Energy

Explanation: Acceleration is defined as the rate of change of velocity with respect to time. Acceleration is a vector quantity, so it includes both magnitude and direction.

Q156. The slope of displacement-time graph is:

• A. Velocity✓
• B. Displacement
• C. Acceleration
• D. Distance

Explanation: The slope of the displacement-time graph gives the velocity of an object while the slope of the distance-time graph gives the speed of an object.

Q157. An alpha particle is ejected from the nucleus of an atom. Which of the following answers describes the change in the nucleus of the atom?

• A. The atomic number increases by 1, and the mass number remains unchanged.
• B. The atomic number increases by 1, and the mass number decreases by 4.
• C. The atomic number increases by 1, and the mass number increases by 2.
• D. The atomic number increases by 2, and the mass number increases by 4.
• E. The atomic number decreases by 2, and the mass number decreases by 4.✓

Explanation: Alpha emission decreases mass number by 4 and atomic number by 2 for each emitted alpha particle. Gamma emission has no effect on the parent atom. Beta emission causes an increase of proton number by 1.

Q158. A force F = 0.12 N is applied on a spring and the spring elongates by 3 cm. The specific constant of the spring is?

• A. 0.4 Nm-2
• B. 40 Nm-1
• C. 400 Nm-1
• D. 4 Nm-1✓

Explanation: k=F/e k=0.12/(3x10-2) k=4 Nm-1

Q159. In rotational motion, angular momentum plays a role which is analogous to that played by _ in linear motion.

• A. Linear velocity
• B. Linear momentum✓
• C. Linear acceleration
• D. Inertia

Explanation: Angular momentum is completely analogous to linear momentum. It has the same implications in terms of carrying rotation forward, and it is conserved when the net external torque is zero. Angular momentum, like linear momentum, is also a property of the atoms and subatomic particles.

Q160. A boy is standing in a lift falling freely under gravity and releases a ball from hand. As seen by the ball, the boy:

• A. Falls down
• B. Remains stationary✓
• C. Falls behind him.
• D. None of above

Explanation: The acceleration of the body does not depend on the mass (for freely falling). Hence both boy and ball have same acceleration. Hence their velocities at every point would be same. So "Relative" velocity is 0. Hence the boy will remain stationary as seen by the ball.

Q161. Alpha rays are nuclear radiations. They are in fact same as the _ nuclei.

• A. Hydrogen
• B. Deuterium
• C. Tritium
• D. Helium✓
• E. Lithium

Explanation: Alpha particle has charge of +2e and mass no 4Hydrogen has a charge of +e and mass no 1Deutrium has charge of +e and mass no 2Tritrium has charge of +e and mass no 3Helium has charge of +2e and mass no 4 Lithium has charge of +3e and mass no 7This confirms that alpha rays are same as the Helium Nuclei.

Q162. When two bodies move towards each other with constant speed, the distance between them decreases at the rate 6m/sec. If they move in the same direction, the distance between them increases at the rate of 4 m/sec. Calculate their velocities.

• A. 5 m/sec, 1 m/sec✓
• B. 3 m/sec, 3 m/sec
• C. 6 m/sec, 1 m/sec
• D. 4 m/sec, 2 m/sec

Explanation: Let's name the two unknown speeds as V1 and V2. From the information given, V1+V2 = 6 V1 - V2 = 4 Solving the equations simultaneously, V1 = 4 + V2 Substituiting this in first equation, 4 + V2 + V2 = 6 2V2 = 2 V2 = 1 m/s V1 = 4 + V2 V1 = 4 + 1 V1 = 5 m/s. Option A is the correct answer.

Q163. The path difference for the constructive interference is:

• A. (n-1)λ
• B. (n+1)λ
• C. n λ / 2
• D. 2n λ
• E. n λ✓

Explanation: Option A: (n-1)λ: This is the path difference for destructive interference. When the path difference is one wavelength less than a whole number of wavelengths, the waves will be out of phase and will cancel each other out. Option B: (n+1)λ: This is also the path difference for destructive interference. When the path difference is one wavelength more than a whole number of wavelengths, the waves will be out of phase and will cancel each other out. Option C: nλ/2: This is the path difference for a node. A node is a point where the waves cancel each other out completely. Option D: 2nλ: This is not possible, as the path difference cannot be greater than the wavelength of the wave. Option E: The path difference for constructive interference is nλ, where n is any integer. This means that the difference in the distance traveled by two waves must be a whole number of wavelengths. When this happens, the waves will be in phase and will add together to create a larger wave.

Q164. The light exhibits the phenomena of constructive interference under the situation when it is _ and _.

• A. Monochromatic and in Phase✓
• B. Monochromatic and out of Phase
• C. In phase and non-monochromatic
• D. Out of phase and non-monochromatic

Explanation: For constructive interference to take place, the waves must be monochromatic (single frequency) and integral multiple of pi or 180 degrees (which implies they must be in phase)

Q165. Which row describes the oscillations of two moving particles in a stationary wave that are separated by a distance of half a wavelength?

• A. A
• B. B
• C. C
• D. D✓

Explanation: 1 full wavelength is 2π or 360°, so half wavelength will have a 180° difference or π. Amplitude will be the same as it is the same particle, unless told otherwise. Hence, option D.

Q166. The net enthalpy change in a chemical reaction is same whether it is brought about in two or more different ways in one or several steps. It is known as:

• A. Joule’s law
• B. Law of conservation of energy
• C. Hess’s law✓
• D. Henry's law

Explanation: According to Hess's law, the thermal effects of a reaction depends upon the initial and final conditions of the reacting substances. It does not depend upon the immediate steps.

Q167. In projectile motion, the range of projectile will be maximum at an angle of:

• A. 30 degrees
• B. 45 degrees✓
• C. 80 degrees
• D. 90 degrees

Explanation: The greatest the value of sin of anything can be is 1. This angle will be at 45 degrees.

Q168. Which of the following is not true?

• A. Momentum is quantity of motion
• B. Unit of momentum is N.s
• C. Momentum is not a vector quantity✓
• D. Momentum is product of mass and velocity

Explanation: Momentum is a vector quantity. The direction of an object's momentum vector is in the direction that the object is moving.

Q169. In perfect elastic collision

• A. Only momentum is conserved
• B. Only total energy is conserved
• C. Only kinetic energy is conserved
• D. Momentum, kinetic energy, and total energy is conserved✓

Explanation: Kinetic energy and hence momentum is conserved only in elastic collision. The kinetic energy is not conserved in inelastic collisions but the total energy is conserved in all types of collisions.

Q170. Two stones, 10kg and 50kg fall through 80m high cliff. Which stone has greater velocity at bottom? (ignoring air resistance) (g=10ms-2)

• A. 10kg
• B. 50kg
• C. Both have same velocity✓
• D. Cannot be calculated

Explanation: If we neglect air resistance both objects reach the ground at the same time so their velocity will be the same.

Q171. A magnetic needle is placed in a uniform magnetic field and is aligned with the field. The needle is now rotated by an angle of 60 degrees and work done is W. The torque on the magnetic needle at this position is

• A. 2√3 W
• B. √3 W✓
• C. √(3/2) W
• D. √(3/4) W

Explanation: This is the following solution:

Q172. Conversion of heat energy completely into work violates:

• A. Zeroth law of thermodynamics
• B. First law of thermodynamics
• C. Second law of thermodynamics✓
• D. Both, the first and second laws of thermodynamics

Explanation: Conversion of heat energy completely into work implies no loss of energy. Second law of thermodyanmics states that not all heat energy can be converted into work in a cyclic process. Therefore, this statement is exactly oopposite to second law of thermodynamics.

Q173. A frictional piston-cylinder based enclosure contains some amount of gas at a pressure of 400k Pa. Then heat is pressure in a quasi-static process. The piston moves up slowly through a height of 10cm. lf the piston has across section area of 0.3m2,the work done by the gas in the process is:

• A. 6kj
• B. 12kj✓
• C. 75kj
• D. 24kj

Explanation: This is the following solution:

Q174. An electric cell of e.m.f E, is connected across a copper wire of diameter d and length L. The drift velocity of electrons in the wire is v0. If the length of the wire is changed to 2L, the new drift velocity of electrons in the copper wire will be:

• A. V
• B. 2V
• C. V/2✓
• D. V/4

Explanation: At constant voltage, the drift velocity is inversely proportional to the length of the conductor. So If the length of the conductor is doubled, the drift velocity will become half of the original value.

Q175. The resultant of two forces of magnitude F and 2F can be:

• A. Less than F
• B. More than 3F
• C. C perpendicular to F✓
• D. Perpendicular to 2F

Explanation: Explanation:

Q176. How much work is done by force of gravity in pulling a stone of weight 10N from the top of 250m high cliff to the foot of cliff?

• A. 250J
• B. 25J
• C. 2500J✓
• D. 25,000J

Explanation: Potential energy = Mgh Mg (weight) is given as 10N So, 250x10=2500.

Q177. When the speed of your car is halved, by what factor does its kinetic energy decrease?

• A. 1/2
• B. 1/4✓
• C. 1/8
• D. 1/6

Explanation: If the speed is halved (keeping the mass same), the kinetic energy decreases, it becomes one-fourth (since kinetic energy is proportional to the square of velocity).

Q178. Relationship between angular and linear velocity is:

• A. ω= rv
• B. v= rω✓
• C. ω= v/r2
• D. v= ω/r

Explanation: Relation Between Linear Velocity and Angular Velocity |v| = rω, which is the relation between linear and angular velocity.

Q179. In a ripple tank 100 waves pass through a certain point in one second. If the wavelength of the wave is 1cm then the speed of the wave will be?

• A. 1 ms-1✓
• B. 2 ms-1
• C. 3 ms-1
• D. 4 ms-1

Explanation: Frequency=100, Wavelength= 1cm = 1/100 = 0.01m. Frequency = Speed/Wavelength (Frequency) (Wavelength) =Speed (100)(0.01)=1m/s.

Q180. Find the resistance if voltage of the circuit is 45 volts and current 30 Amp.

• A. 1.6 ohm
• B. 1.5 ohm✓
• C. 1.7 ohm
• D. 1.8 ohm

Explanation: R = V / ISubstituting the given values, we get:R = 45 V / 30 A = 1.5 ohmTherefore, the resistance of the circuit is 1.5 ohm

Q181. If a charged particle is at rest but we are seeing it from a train then we observe ----------------

• A. Electric field
• B. Magnetic field
• C. Both fields✓
• D. None of these

Explanation: Option C is correct since for us the charge is moving and creating a magnetic field along with electricity.

Q182. The charge on gamma rays is _.

• A. 1+
• B. 1-
• C. 0✓
• D. None of these options are correct

Explanation: Option C is correct since 'Gamma rays' have no charge so are unaffected by magnetic and electric fields.

Q183. KE of body is increased by 44 %, what is the percentage increase in the momentum?

• A. 10%
• B. 20%✓
• C. 30%
• D. 40%

Explanation: Now, let's analyze the relationship between kinetic energy (KE) and momentum (P) of an object:Kinetic Energy (KE) = (1/2) * m * v^2Momentum (P) = m * vWhere:m = mass of the objectv = velocity of the objectSince momentum (P) is directly proportional to the velocity (v) of the object, any change in the kinetic energy (KE) that is solely due to a change in velocity will lead to an equal percentage change in momentum (P).Given that the kinetic energy is increased by 44%, this means the velocity is increased by some percentage as well. Since we have no information about the mass of the object or the specific change in velocity, we cannot determine the exact percentage increase in momentum. Therefore, the correct answer is: b) 20%. Option B is correct since:

Q184. A thermodynamic system undergoes a process in which its internal energy decreases by 300 J. If at the same time 120 J of work is done on the system, find the heat lost by the system.

• A. -420 J✓
• B. 420 J
• C. 80 J
• D. -80 J

Explanation: ΔU=∆Q-∆W∆Q=∆U+∆W∆Q=-300+(-120)= -300-120 = -420 J

Q185. The length of a conductor is halved. Its resistance will be _.

• A. Halved✓
• B. Doubled
• C. Unchanged
• D. Quadrupled

Explanation: Length of conductor is halved, the resistance will be halved too, both are directly proportional to each other

Q186. When a charged particle enters in a strong magnetic field, its kinetic energy _.

• A. Decreases
• B. Increases then decreases
• C. Becomes zero
• D. Remains constant✓

Explanation: When a charged particle enters a strong magnetic field, its kinetic energy remains constant. if no work is done on the charged particle, its kinetic energy remains constant. Thus, the correct answer is option D: "Remains constant."

Q187. The concept of work function was given by _.

• A. Bohr
• B. Einstein✓
• C. Rutherford
• D. None of these options is correct

Explanation: Einstein gave the concept of work function.

Q188. Electric potential difference between two points can be defined as _.

• A. Difference of the kinetic energy per unit charge
• B. Difference of the kinetic energy
• C. Difference of the potential energy per unit charge✓
• D. Difference of the potential energy

Explanation: The electric potential difference between two points can be defined as the difference of potential energy per unit charge. Electric potential difference, also known as voltage, is a measure of the work done to move a unit positive charge between two points in an electric field. It is often represented by the symbol V.

Q189. Maximum power is delivered when internal resistance of the source is equals to _.

• A. Zero resistance
• B. Load resistance✓
• C. Max resistance
• D. None of these options are correct

Explanation: The maximum power is delivered to a load when the load resistance is equal to the internal resistance of the source.

Q190. A monochromatic light is incident on two slits and an interference pattern is produced on a screen at distance L. Now one slit is covered, and no light comes from it. What is the change in pattern on the screen?

• A. The width of central maximum is decreased
• B. The width of outer maximum is decreased
• C. The intensity of central maximum will decrease
• D. Less number of fringes will be observed✓

Explanation: Option D is correct since there will be less fringes on the screen since one slit is covered and no light coming from it.

Q191. A body moves a distance of 10 m along a straight line under the action of 5 N force. If work done is 25 J, then angle between the force and direction of motion of the body will be _.

• A. 75˚
• B. 60˚✓
• C. 45˚
• D. 30˚

Explanation: Option B is correct since we know that, W = FS cosθ Cosθ = W / FS Cosθ = 25 / 50 Cosθ = 1 / 2 θ = 60 Options A, C, and D are incorrect since they do not apply the formula.

Q192. A 300 W heater is used to boil 500g of water at 100˚C. How long should the heater be switched on? (The specific latent heat of vaporization of water is 2230 J/g)

• A. 62 mins✓
• B. 62 secs
• C. 1.5 hour
• D. 0.5 hour

Explanation: Option A is correct since we know that, mc / p So t = 500 x 2230 / 300 = 3717s t = 3717 / 60 = 62 mins

Q193. A body of mass 10 kg is moved parallel to the ground, through a distance of 2 m. The work done against gravitational force is _.

• A. Zero✓
• B. 196 J
• C. -196 J
• D. 48 J

Explanation: Option A is correct since gravitational force only works perpendicular to the ground, so no work is done against gravitational force. Options B, C, and D are incorrect since no work can be done against gravitational force.

Q194. 12,32,72,152 _

• A. 312✓
• B. 325
• C. 515
• D. 613

Explanation: 12+20=32 32+40=72 72+80=152 so 160 should be added in 152 152+160=312

Q195. 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

Q196. What letter comes next in the following series? B D G K P

• A. C
• B. E
• C. B
• D. V✓
• E. Q

Explanation: B c D D e f G G h i j K K l m n o P P q r s t u V

Q197. Children go to school because:

• A. they want to learn poems.
• B. they want to be away from home.
• C. They want to look beautiful.
• D. they want to gain knowledge.✓
• E. they want to tease the teacher.

Explanation: The question is asking for the purpose of schooling.

Q198. 3, 6, 18, 72, _

• A. 144
• B. 216
• C. 288
• D. 360✓

Explanation: The pattern is: Times 2, Then times 3, Then times 4, So times 5 to get 360

Q199. If 7(x-2) = 3x - 2. What is the value of x?

• A. -4
• B. -3
• C. 2
• D. 3✓
• E. 4

Explanation: You can sovle this problem as shown below: