Etea Mdcat 2017 — Solved Past Paper with Answers

Q1. I enjoy _ tennis

• A. To play
• B. Plays
• C. Playing✓
• D. To playing

Explanation: The most relevant and accurate is C. I enjoy playing tennis.

Q2. The path _ paved, so we were able to walk through the path.

• A. Had been✓
• B. Was
• C. Has been
• D. Being

Explanation: We use 'had been' when you describe something that happened in the past before something else in the past. Also an action that had happened in the past and does not reflect any continuation to the present time. The path had been paved, so we were able to walk through the path.

Q3. Choose the correct sentence.

• A. Does your tram leaw before eight o'clock?
• B. Does your train leave before eight clock?
• C. Does your train leave before eight o'clock?✓
• D. Do your train leave before eight o'clock?

Explanation: The correct sentence is Option C: "Does your train leave before eight o'clock?" This sentence correctly uses "Does" as the auxiliary verb with the singular subject "your train" to form the present tense question. It also includes the correct spelling of "leave" and "o'clock."Option A is incorrect due to the misspelling of "leaw," which should be "leave." Option B omits "o'clock," making it incomplete in expressing time. Option D uses "Do" incorrectly with the singular subject "train," which requires "Does."

Q4. Choose the correct narration:He asked me what my name was and what I did

• A. He said to me, ’’What was my name and what did I do?”
• B. He said to me, ’’What is your name and what do you do?”✓
• C. He said to me, ’’What my name was and what I did?”
• D. He said to me, ’’What his name was and what did he do?”

Explanation: He said to me, “What is your name and what do you do?” This is direct narration. The words spoken are repeated.

Q5. Choose the antonym from the word “Abrogate”.

• A. Transgress
• B. Signify
• C. Alleviate
• D. Ratify✓

Explanation: ‘Ratify’ means to officially sign an agreement, and give a formal consent. It is an antonym of the given word, and hence, the option is correct. Abrogate’ means to break a law or agreement. We have to find the antonym (a word that is opposite in meaning) of the given word. Antonym means opposite. So D is the correct answer.

Q6. While the city has earned record revenue this year, _ well behind in exports:

• A. It still lag
• B. It still lags✓
• C. It lag still
• D. It lags still

Explanation: While the city has earned record revenue this year, it still lags well behind in exports. This is the most accurate and relevant term used.

Q7. Every person must learn _ ?

• A. That how wisely his time can be used.
• B. To make wise use of his time.✓
• C. That this time need a wise uses.
• D. To using his time in a wisely manner

Explanation: Every person must learn to make wise use of his time. This is the correct term used.

Q8. “He is busy. Would you like to leave a message?”, said the assistant.

• A. The assistant told that he is busy and asked me to leave a message.
• B. The assistant told that he is busy and ask me to leave a message
• C. The assistant told that he was busy and asked me to leave a message.✓
• D. The assistant told that he is busy and asked me to leave a message.

Explanation: Option C is more accurate and formal. The assistant told that he was busy and asked me to leave a message.

Q9. Chose the antonym of the word “Untenable”

• A. Tender
• B. Sheepish
• C. Supportable✓
• D. Tremulous

Explanation: Untenable means ‘unjustified’ or ‘flawed’ so its opposite will be ‘supportable’

Q10. Why did your supervisor take such a strong disciplinary action when you were innocent ?

• A. Why has such a strong disciplinary action taken by your supervisor when you were innocent ?
• B. Why was such a strong disciplinary action being taken by your supervisor when you were innocent ?
• C. Why was such a strong disciplinary action taken by your supervisor when you were innocent ?✓
• D. Why such a strong disciplinary action was taken by your supervisor when you were innocent?

Explanation: The only correct option is C. Students should note that in option A, ‘has’ is incorrect, in option B ‘being taken’ is incorrect while in option D, there is no ‘why’ before ‘such’ so it is also wrong

Q11. He is grieving _ his deceased father.

• A. At
• B. For✓
• C. On
• D. Over

Explanation: The correct preposition is ‘for’ so option is correct

Q12. That a driver swerves in order to avoid an accident can be proven by examining themarks on the pavements.(The underlined word nearly means)

• A. Stops quickly
• B. Turns sharply✓
• C. Hits something else
• D. Goes backward

Explanation: Swerve means to deviate / change course so option B is correct

Q13. Though Aleem is poor _ he is honest.

• A. But
• B. Nevertheless
• C. Yet✓
• D. Still

Explanation: ‘Yet’ is a conjunction that is used to show contrast

Q14. Choose the synonym for the word “Abridge”.

• A. To make a bridge
• B. Shorten✓
• C. Magnify
• D. Divert

Explanation: Abridge means to cut / trim which is a synonym for shorten

Q15. It is a general perception that doctors have a callous disregard for feeling of others;(The underlined word nearly means)

• A. Respectable
• B. Careful
• C. Unfeeling✓
• D. Sensitive

Explanation: Doctors are often said to be heartless / cold-hearted and this matches with option C i.e unfeeling

Q16. Choose the synonym for the word “Attenuate”.

• A. Appear
• B. Be absent
• C. Weaken✓
• D. Testify

Explanation: Attenuate means loss so it’s synonym can be option C i.e weaken

Q17. The rules forbid passengers to cross the railway line.

• A. Passenger was forbidden by the rules to cross the railway line.
• B. Passenger are being forbidden by the rules to cross the railway line.
• C. Passengers are forbidden by the rules to cross the railway line.✓
• D. Passenger is forbid by the rules to cross the rail way line.

Explanation: Option C has the correct indirect form of the sentence with passengers being plural, followed by ‘are’

Q18. A thrifty buyer purchases fruits and vegetables in season.(The under lined word nearly means)

• A. Careful✓
• B. Professional
• C. Disinterested
• D. Healthy

Explanation: Thrifty means to save money or be frugal so it best matches with careful

Q19. For callus formation, auxin and cytokinin are required in what ratio?

• A. Balanced
• B. Only cytokinin required
• C. Low auxin, very high cytokinin✓
• D. Only auxin

Explanation: The ratio of auxin to cytokinin plays an important role in the effect of cytokinin on plant growth. Cytokinin alone does not affect parenchyma cells. When cultured with auxin but no cytokinin, they grow large but do not divide. When cytokinin is added, the cells expand and differentiate. When cytokinin and auxin are present in equal levels, the parenchyma cells form an undifferentiated callus, so it can't be used. More cytokinin induces the growth of shoot buds, while more auxin induces root formation.

Q20. For which purpose are myeloma cells (cancerous B lymphocytes) used in the production of monoclonal antibodies?

• A. Increased rate of cell division
• B. Immunization with antigen✓
• C. To avoid contamination
• D. As nutrient in media

Explanation: Multiple myeloma cells are abnormal plasma cells (a type of white blood cell) that build up in the bone marrow and form tumors in many bones of the body. They are produced for immunization with an antigen, as Vaccines contain weakened or inactive parts of a particular organism (antigen) that triggers an immune response within the body.

Q21. DNA polymerase adds nucleotides to the 3’ end of the primer so the direction of replication will be?

• A. 5’ to 3’✓
• B. 3’ to 5’
• C. 3’ end of the primer to 3’ end of template strand
• D. 3’ end of the template strand to the 3’ end of the primer

Explanation: DNA polymerase is able to add nucleotides only in the 5′ to 3′ direction (a new DNA strand can be extended only in this direction). It also requires a free 3′-OH group to which it can add nucleotides by forming a phosphodiester bond between the 3′-OH end and the 5′ phosphate of the next nucleotide.

Q22. When the sperm count is high, inhibin hormone release increases which:

• A. Inhibits anterior pituitary release follicle stimulating g hormone✓
• B. Increase anterior pituitary release of follicle stimulating hormone
• C. Inhibit release of luteinizing hormone
• D. Increaserelease of luteinizing hormoneave

Explanation: When the sperm count exceeds set limits,The hormone inhibits GnRH and FSH, decreasing the activity of the Sertoli cells. It inhibits the synthesis and release of the follicle-stimulating hormone in the pituitary gland and reduces the hypothalamic LH - releasing hormone content.

Q23. Implantation of the embryo takes place in which week of pregnancy?

• A. 1st
• B. 2nd✓
• C. 3rd
• D. 4th

Explanation: In the second week of pregnancy, the zygote continues to divide and forms a ball of cells called a blastocyst. The blastocyst further develops as it moves down the fallopian tube and towards the uterus. By the end of the second week implantation of the blastocyst in the endometrium begins.

Q24. XX-XY type of sex determination pattern is present in which of the following organisms?

• A. Humans
• B. Butterflies
• C. Grasshopper
• D. Drosophila
• E. Both A and D✓

Explanation: The XY sex-determination system is the sex-determination system found in humans, most other mammals, some insects (Drosophila), and some plants (Ginkgo).

Q25. If the medulla oblongata of a person brain is damaged which of the following process will be disturbed?

• A. Thinking
• B. Sleep
• C. Thirst
• D. Swallowing✓

Explanation: The medulla oblongata is a structure found in the human brain. The major function of the Medulla oblongata is to control automatic functions (that is, not under human control) breathing, respiration, and heartbeat. It also helps in body secretion, reflexes, swallowing, coughing, and sneezing.

Q26. Otitis media is an inflammation of which part of the

• A. Brain
• B. Middle ear✓
• C. Lungs
• D. Urinary tract

Explanation: Otitis media is an inflammation of the middle ear. The eustachian tubes equalise the pressure between the middle ear cavity and the outside mucus to drain out of the middle ear cavity. Inflammation of the middle ear causes the tubes to close, causing the fluid to become trapped. Bacteria travel from the back of the nose through the fluid in the eustachian tube directly into the middle ear cavity and multiply in the fluid.

Q27. In which of the following disorders is the structure and function of the normal spinal cord damaged?

• A. Arthritis
• B. Sciatica
• C. Spondylosis✓
• D. Disc slip

Explanation: When Osteoarthritis affects the spine, it is known as Spondylosis. Due to the change in the structure and function of the spinal cord, the major symptoms are often an unsteady, jerky walk, pain, and loss of flexibility in the neck. This disease is more common in people older than 60. The main cause is aging.

Q28. The experiments by Hershey and Chase helped confirm that DNA was the hereditary material on the basis of the finding that :

• A. Radioactive phage were found in the pellet
• B. Radioactive cells were found in the supernatant
• C. Radioactive sulfur was found inside the cell
• D. Radioactive phosphorus was found in the cell✓

Explanation: The experiments by Hershey and Chase helped confirm that DNA was the hereditary material as radioactive phosphorus was found in the cell.The Hershey-Chase experiments were not the first studies to oppose the prevailing theory in the early 1900s that genetic material was composed of proteins. In 1944, nearly a decade before Hershey and Chase’s work, scientists published sound evidence that genes were made of DNA rather than protein so it was confirmed by presence of phosphorus.

Q29. How many nucleotides are in 12 mRNA codons?

• A. 12
• B. 24
• C. 36✓
• D. 48

Explanation: 12 mRna codons there are 36 nucleotides. As 3 nucleotide cob]combine to form one codon so 3 multiply by 12 gives 36.

Q30. Which of the following is the suitable vector to be incorporated with the large external DNA fragment?

• A. Small size vector✓
• B. Large size vector
• C. Large size vector with no origin of replication
• D. Small size vector with no origin of replication

Explanation: In molecular cloning, a vector is a DNA molecule used as a vehicle to artificially carry foreign genetic material into another cell, where it can be replicated and/or expressed. A vector containing foreign DNA is termed recombinant DNA. A small size is the suitable vector to be incorporated with the large external DNA fragment because it should be small in size so that it can easily integrate into the host cell. It should be capable of inserting a large segment of DNA. It should possess multiple cloning sites.

Q31. Which of the following nutrient is incorrectly paired with its function in plant?

• A. Iron-cytochromes and chlorophyll
• B. Molybdenum cell permeability✓
• C. Cobalt- Required by nitrogen fixers
• D. Calcium- formation of cell wall.

Explanation: Molybdenum is an essential component in two enzymes that convert nitrate into nitrite (a toxic form of nitrogen) and then into ammonia before it is used to synthesize amino acids within the plant. It is also needed by symbiotic nitrogen fixing bacteria in legumes to fix atmospheric nitrogen. So it cannot be used in cell permeability thus option b is incorrect.

Q32. Which cell are the responsible for movement of sugar as per mass flow hypothesis.

• A. Tracheids, vessels, elements
• B. Tracheids, Companion cells
• C. Vessels elements, companion cells
• D. Companion cell, sieve-tubes✓

Explanation: Phloem sieve-tube elements have reduced cytoplasmic contents, and are connected by a sieve plate with pores that allow for pressure-driven bulk flow, or translocation, of phloem sap.The mass flow hypothesis is a theory that tells about how the sap flows through the phloem. This theory or hypothesis was first proposed in 1930 by German physiologist Ernst Munch. This theory tells us how simple sugar or a sugar that is highly concentrated organic sugar, is transported to other parts of a plant thus companion cells and sieve tubes are involved.

Q33. After buying green bananas or unripe avocados, they can be kept in a brown bag to ripen. The hormones released by the fruit and trapped in the bag are probably

• A. Abscises acid
• B. Cytokinin
• C. Ethylene✓
• D. Gibberellic acid

Explanation: Ethylene is a colorless, flammable, gaseous unsaturated hydrocarbon, C2H4, and occurs in plants functioning especially as a natural growth regulator that promotes the ripening of fruit. Ethylene production is regulated by a variety of developmental and environmental factors. During the life of the plant, ethylene production is induced during certain stages of growth, such as germination, ripening of fruits, abscission of leaves, and senescence of flowers.

Q34. For the location/detection of a gene in a DNA library which of the following is used?

• A. Primer
• B. Probe✓
• C. Restriction enzyme
• D. Taq Polymerase

Explanation: A probe is a single-stranded sequence of DNA or RNA used to search for its complementary sequence in a sample genome. DNA probes are important tools in diagnostics to ensure high specificity and sensitivity. They are used in molecular biology methods like PCR. Fluorescence in situ hybridization (FISH) is a laboratory technique for detecting and locating a specific DNA sequence on a chromosome. The technique relies on exposing chromosomes to a small DNA sequence called a probe that has a fluorescent molecule attached to it.

Q35. Under UV illuminator, DNA bands are seen in agarose gel due to which of the following?

• A. Agarose
• B. Charge in DNA
• C. Fluorescent dye✓
• D. Radioactive dye

Explanation: Fluorescent dyes, also known as reactive dyes or fluorophores are used for locating dna bands. Fluorescence is used in biology as a non-destructive way of analysing biological molecules, even at low concentrations, by means of the molecule's intrinsic fluorescence, or by attaching it with a fluorophore therefore dna bands can easily be seen.

Q36. Which of the following is a non-sense codon?

• A. UGA✓
• B. UAU
• C. CAU
• D. GAU

Explanation: Stop codons are also called nonsense codons because they do not code for an amino acid and instead signal the end of protein synthesis. Thus, nonsense mutations occur when a premature nonsense or stop codon is introduced in the DNA sequence.Stop codons (UAA, UAG or UGA) are recognized by release factors which bind into the A-site and use an activated water molecule to hydrolyze the ester linkage between the completed polypeptide and tRNA.

Q37. If a disorder is not present in a child family but the fetus itself is infected before birth, it is known as:

• A. Somatic Mutation
• B. Hereditary mutation
• C. Germ line mutation
• D. De novo mutation✓

Explanation: De navo mutation is A genetic alteration that is present for the first time in one family member as a result of a variant (or mutation) in a germ cell (egg or sperm) of one of the parents, or a variant that arises in the fertilized egg itself during early embryogenesis.De novo gene birth is the process by which new genes evolve from DNA sequences that were ancestrally non-genic.

Q38. What will happen if a nucleotide is deleted from a gene having 9 nucleotides in its transcriptional unit?

• A. Change in Phenotype✓
• B. No change in Phenotype
• C. Synthesis of 3 amino acids.
• D. Synthesis of 4 amino acids.

Explanation: A deletion changes the DNA sequence by removing at least one nucleotide in a gene.Phenotypic effects of deletions depend on the size and location of deleted sequences on the genome. If the nucleotide is deleted this effect amino acid sequence thus primary secondary or tertiary structure is disturbed protein becomes non functional.

Q39. If one of the following components is missing , bacteria can not increase the number of its plasmid copies.

• A. Antibiotic resistance gene
• B. Origin of replication✓
• C. Cloning site
• D. Ligases enzymes

Explanation: An essential feature of bacterial plasmids is their ability to replicate as autonomous genetic elements in a controlled way within the host. Therefore, they can be used to explore the mechanisms involved in DNA replication and to analyze the different strategies that couple DNA replication to other critical events in the cell cycle therefore they can replicate to increase the number of plasmid.

Q40. Identify the mismatch pair in the following:

• A. Cyanobacteria – primary producer
• B. Grasshopper – primary producer
• C. Fungi – Decomposer
• D. Zooplankton – secondary consumer✓

Explanation: Zooplankton is a primary consumer NOT a secondary consumer.

Q41. What will happen if a vector (plasmid) is cut with a different restriction enzyme which cuts the external DNA to be incorporated in the vector (plasmid)?

• A. Ligation
• B. No ligation✓
• C. Tight ligation
• D. Cloning

Explanation: If the vector and insert are cut with different restriction enzymes, their ends are not compatible, so DNA ligase cannot join them. As a result, ligation does not occur, and the recombinant plasmid is not formed.

Q42. Sarcolemma is the membrane around?

• A. Bone
• B. Joints
• C. Muscle fiber✓
• D. Heart

Explanation: The correct answer is muscle fiber because the sarcolemma is the plasma membrane that surrounds each muscle cell or fiber. It plays a crucial role in transmitting electrical impulses that trigger muscle contraction. The other options refer to different types of membranes: the periosteum for bones, the synovial membrane for joints, and the pericardium for the heart, each serving distinct functions unrelated to the sarcolemma.

Q43. The deficiency of calcitonin results in ?

• A. Bone formation
• B. Kidney stone✓
• C. Hyperthyroidism
• D. Hypothyroidism

Explanation: A diet low in calcium actually increases one’s risk of developing kidney stones. A lack of calcitonin in the blood may increase a person’s risk of bone degradation and osteopenia.

Q44. In which of the following the female workers are sterile?

• A. Ants
• B. Honeybee✓
• C. Baboon
• D. Parrots

Explanation: The worker bee and the queen bee are both female but only the queen bee can reproduce. All drones are male. Worker beans clean the hive, collecting Pollen and nectar to feed the colony and they take care of the offsprings. The drones only job is to mate with the queen with the queen

Q45. If in solution some bacteria infected by a certain phages had somehow developed the ability to make a particular amino acid that was not in their genes before. What would be the possible explanation to his new ability ?

• A. Induction
• B. Transformation
• C. Transduction✓
• D. Conjugation

Explanation: Transduction is the process by which a virus transfers genetic material from one bacterium to another. Viruses called bacteriophages are able to infect bacterial cells and use them as hosts to make more viruses with new genes.

Q46. Identify in which of the following the genetic information is catalyzed using reverse transcription;

• A. Protein→DNA
• B. RNA →DNA✓
• C. DNA→RNA
• D. RNA Protein

Explanation: A reverse transcriptase(RT) is an enzyme used to generate complementary DNA(cDNA) from an RNA template, a process termed reverse transcription.

Q47. Which one is not an opportunistic disease related to HIV infection:

• A. Destruction of body immune system✓
• B. Recurrent pneumonia
• C. Pulmonary tuberculosis
• D. Toxoplasmosis

Explanation: People with aids have badly damaged immune systems. They get an increasing number of severe illnesses called opportunistic infections which include tuberculosis toxoplasmosis and pneumonia.

Q48. Approximately how much calories of free energy is stored in plant biomass for every mole of CO2 fixed during photosynthesis ?

• A. 110
• B. 112
• C. 114✓
• D. 116

Explanation: The conversion of carbon dioxide (CO2) and water (H2O) into glucose (C6H12O6) involves the capture of light energy and its conversion into chemical energy. The actual energy stored in the glucose molecule can then be released through cellular respiration to produce ATP. The estimate of 114 kilocalories per mole of CO2 fixed likely considers the overall efficiency of photosynthesis and subsequent energy transfer processes. However, it's crucial to note that this is an approximation, and the actual energy yield can vary. Different sources and studies might provide slightly different estimates based on specific conditions and assumptions.

Q49. Which of the following vaccine has least side effects:

• A. Attenuated vaccine
• B. Killed vaccine✓
• C. Subunit vaccine
• D. Toxoid vaccine

Explanation: Killed vaccine has least side effect. An inactivated vaccine (or killed vaccine) is a vaccine consisting of virus particles, bacteria, or other pathogens that have been grown in culture and then killed to destroy disease-producing capacity. It has the least side effects.

Q50. The first that oxygenated the atmosphere were:

• A. Cyanobacteria✓
• B. Phototrophic organisms
• C. Anaerobic organisms
• D. All of the above

Explanation: It is a fact that the first organisms that oxygenated the atmosphere were cyanobacteria

Q51. What event is thought to have contributed to the evolution of eukaryotes ?

• A. Global warming
• B. Glaciations
• C. Volcanic activity
• D. Oxygenation of the atmosphere✓

Explanation: The production and release of oxygen, by cyanobacteria and algae, lead to evolution of eukaryotic cells as they contain a membrane-bound nucleus and are the building blocks of complex multicellular organisms

Q52. Which of the locomotor organ would likely be the shortest?

• A. A flagellum
• B. A cillium✓
• C. An extended pseudopod
• D. A pellicle

Explanation: Pellicle is a thick cuticle and it is not a locomotor organ so option D is incorrect. Whereas pseudopods are cytoplasmic extensions. Among ciliium and flagellum, option B is correct since cilium is shorter in comparison.

Q53. One of the following statement is true regarding Basidiomycota.

• A. They are most important source of antibiotics
• B. They have no known sexual stage.
• C. Hyphae fuse to give rise to dikaryotic mycelium✓
• D. The vast majority of spores are formed asexually

Explanation: Basidiomycota are fungi composed of hyphae, which gives rise to dikaryotic mycelium

Q54. The sprouting gametophyte of a moss consists of a filamentous, branched structure called:

• A. Mycelium
• B. Hyphae
• C. Protonema✓
• D. Bud

Explanation: Mycelium is part of the fungi kingdom and is the network of threads, called hyphae and a bud is an undeveloped or embryonic shoot so option A, B and D are incorrect, leaving option C to be correct

Q55. Which seedless plant is a renewable source of energy ?

• A. Club moss
• B. Horsetail
• C. Sphagnum moss✓
• D. Fern

Explanation: Sphagnum moss because it can be used as carbon or coal for heating

Q56. In order to see various aspects of specimen a three dimensional image of the object can be produced using:

• A. Compound microscope
• B. Dark microscope
• C. Transmission electron microscope
• D. Scanning electron microscope✓

Explanation: Compound microscope produces a 2-D image, dark microscope illuminates sample against a dark background, Transmission electron microscope also produces 2-D images whereas only scanning electron microscope produces 3-D image so option D is correct

Q57. The usual position of the two centrioles in relation to each other is at right angle in:

• A. Higher plant cells
• B. Lower plant cells
• C. Animals cells
• D. Both (B) &(C)✓

Explanation: Only lower plant cells and animal cells have centrioles at right angle to each other so correct option is D

Q58. Rhizobium belongs to:

• A. Beta-protobacteria
• B. Gama-protobacteria
• C. Alpha-protobacteria✓
• D. Delta-protobacteria

Explanation: Rhizobium belongs to alpha proto-bacteria, this is a fact and has to be learnt

Q59. Poisonous red-tides in coastal area are caused by the blooms

• A. Euglenoids
• B. Rhodophyta
• C. Diatoms
• D. Dinoflagellates✓

Explanation: Poisonous red tides are caused by algae so the correct option is D i.e Dinoflagellates

Q60. Acetabularia mediterranea is:

• A. A fungus
• B. An algae✓
• C. A protozoan
• D. A prokaryote

Explanation: Students should learn that Acetabularia Mediterranea is a green algae

Q61. Double fertilization occurs in:

• A. Pinus
• B. Ferns✓
• C. Marchantia
• D. Maize

Explanation: Double fertilization of this type is unique to flowering plants (angiosperms) so the correct option is B i.e ferns

Q62. Most conspicuous sea-weeds are:

• A. Red-algae
• B. Blue-algae
• C. Green-algae
• D. Brown-algae✓

Explanation: Students should learn that most conspicuous sea-weeds are brown algae

Q63. An acrinus is composed of:

• A. 10-20 Acinars
• B. 20-40 Acinars✓
• C. 20-30 Acinars
• D. 30-40 Acinars

Explanation: The pancreatic acinar cell is a highly specialised structure developed for synthesis, storage, and secretion of digestive enzymes. This is a fact that needs to be learned.

Q64. 2-FADH2 can yield energy:

• A. 4 ATP✓
• B. 8 ATP
• C. 6 ATP
• D. 10 ATP

Explanation: 1 FADH2 = 2 ATP so 2 FADH2 = 4 ATP

Q65. ABO Blood groups are an example of:

• A. Multiple alleles and incomplete dominance
• B. Co dominance and incomplete dominance
• C. Incomplete dominance only
• D. Multiple alleles and co dominance✓

Explanation: The human ABO blood group system exhibits codominance. It consists of three alleles A, B, and O. Both A and B show codominance

Q66. In a mating between two individuals those are heterozygous for a recessive lethal allele.What genotypic ratio (homozygous dominant : heterozygous : homozygous recessive) would you expect to observe in the offspring?

• A. 1:2:1✓
• B. 3:1:1
• C. 1:2:0
• D. 0:2:1

Explanation: Explanation is given below

Q67. If a new born baby possesses carboxyhemoglobin instead of the oxyhemoglobin, the condition may be:

• A. Embolism
• B. Atherosclensis
• C. Cyanosis✓
• D. Arteriosclerosis

Explanation: Cyanosis indicates there may be decreased oxygen attached to red blood cells in the bloodstream. It may suggest a problem with the lungs or heart so option C is correct as carboxyhemoglobin reduces blood supply to the body

Q68. Of 100 ml of arterial blood, oxygen provided to the tissues is:

• A. 2ml
• B. 3ml
• C. 4ml
• D. 5ml✓

Explanation: 6 mL of oxygen is delivered, at tissue level in normal conditions so option D is correct

Q69. Nervous system that prepares itself for fight or flight:

• A. Para sympathetic
• B. Sympathetic✓
• C. Somatic
• D. Peripheral

Explanation: The parasympathetic nervous system predominates in quiet “rest and digest” conditions while the sympathetic nervous system drives the “fight or flight” response in stressful situations

Q70. If black and white true breeding mice are mated and they result is all gray offspring, what inheritance pattern would this be indictive of ?

• A. Dominance
• B. Co dominance
• C. Multiple alleies
• D. Incomplete dominance✓

Explanation: Codominance means that no allele can block or mask the expression of the other allele. While incomplete dominance is a condition in which a dominant allele does not completely mask the effects of a recessive allele so the correct option is D as black and white parents produce gray offsprings

Q71. Which of the following do not play a role in intra cellular movement?

• A. Microfilament and inter mediate filaments
• B. Microfilaments and microtubules
• C. Inter mediate filaments and micro tubules✓
• D. Only microfilaments

Explanation: The functional roles for microfilaments involve cell membrane motility, endo- and exocytosis, secretion and vesicle transfer so option A,B,D are incorrect leaving with C being the correct option as microtubules and intermediate filaments, form the cell cytoskeleton

Q72. Which statement about thylakoids in eukaryotes is not correct ?

• A. Thylakoids are assembled into stacks
• B. Thylakoids exist as a maze of folded membranes.✓
• C. The space surrounding thylakoids is called stroma.
• D. Thylakoids contain chlorophyll.

Explanation: Thylakoids are stacks of granum, they are surrounded by stroma that is the colorless fluid surrounding the grana within the chloroplast. Thylakoids are called photosystems as they contain chlorophyll, which absorbs light energy. The only incorrect statement is option B which is the answer

Q73. The three non-infective genes in HIV are;

• A. gag, pol, rev
• B. gag, pol, vpu
• C. gag, pol, vpr
• D. gag, pol, env✓

Explanation: Students should learn that gag, pol, env are the 3 non-infective genes of HIV

Q74. Macronutrients are:

• A. K-Mg-N-P✓
• B. Cu-Mg-Mn-S
• C. Mn-S-P-Cu
• D. Mg-Mn-Ca-P

Explanation: The macronutrients are K-Mg-N-P (Students should learn this as it is a fact)

Q75. Sphagnum is also called as:

• A. Sphenopsida
• B. Peat Moss✓
• C. Club moss
• D. Maiden hair ferns

Explanation: Sphagnum is also called bog moss or sphagnum moss

Q76. PGAL is formed during the oxidative phase of _.

• A. Calvin Cycle✓
• B. Glycolysis
• C. Oxidative Phosphorylation
• D. None of the above options are correct.

Explanation: PGA formed in the Carbon fixation of calvin cycle is reduced into phosphoglyceraldehyde. The products of light reaction i.e. NADPH and ATP used in this process. Each molecule of phosphoglyceric acid (PGA) receives energy from ATP and hydrogen from NADPH of light reaction, forming phosphoglyceraldehyde (PGAL) and water.

Q77. Innate behaviour is:

• A. None of these
• B. Acquired through observing other's behaviours
• C. Is a part of inherited structure✓
• D. Acquired through learning from stimuli

Explanation: Innate behavior is a behavior that is inherited by an organism and can be performed without prior experience.

Q78. In the intestine amino acids are absorbed by?

• A. Capillaries✓
• B. Lacteals
• C. Both A and B
• D. None of the above options are correct

Explanation: Amino acids produced by the digestion of proteins are absorbed from the intestine through blood capillaries in the microvilli. Microvilli increase the surface area of the small intestine and also are rich in blood capillaries.Most absorption of amino acids occurs in the jejunum; there is a lesser contribution from the ileum.

Q79. What is the name of the carboxylic acid given below?HOOC(CH2)3COOH

• A. Propanedioic acid
• B. Pentane dioic acid✓
• C. Pentane dicarboxylic acid
• D. Propane dicarboxylic acid

Explanation: d) Propane dicarboxylic acidThis option is correct. Propane dicarboxylic acid has three carbon atoms in its chain and two carboxyl groups, with the formula HOOC-(CH2)2-COOH. The given structure, HOOC(CH2)3COOH, also has three carbon atoms in its chain and two carboxyl groups, so it is propane dicarboxylic acid.

Q80. OH-(alcoholic) +CH3(CH2)2Br- →Product+Product. The nature of OH in the above reaction is:

• A. Nucleophile
• B. Lewis base✓
• C. Ligand
• D. All of the above

Explanation: Detailed Explanation:In the reaction presented, alcoholic OH- serves primarily as a Lewis base. It abstracts a proton from the β-carbon, leading to the elimination of the halide and the formation of an alkene through an E2 mechanism. While it can also act as a nucleophile, the context of the reaction indicates that its role as a base is more significant here.Option A (Nucleophile) is incorrect because, although OH- can act as a nucleophile, in this specific reaction, it primarily functions as a base in the elimination process.Option C (Ligand) is incorrect since there are no metal ions to bind with, ruling out the possibility of OH- being a ligand.Option D (All of the above) is incorrect because not all previous options hold true, specifically Options A and C.

Q81. The bond energy of (H2 )molecule (H2→2H) is:

• A. 436Kj/mol✓
• B. 40.7 Kj/mol
• C. 272 Kj/mol
• D. 436÷Avagadros no Kj/mol

Explanation: Bond energy is the amount of energy required to break one mole of covalent bonds in a gaseous molecule, resulting in separate gaseous atoms. The bond energy of the H2 molecule can be determined experimentally by measuring the energy required to break the bond in the H2 molecule.The experimental value of the bond energy of H2 is approximately 436 kJ/mol.(It is a fact and should be memorized.)

Q82. Considering the molecular orbital theory (MOT), chooses the correct relative energies order.

• A. σ1s<σ*1s< σ2s< σ* 2s< σ2px< π2py = π2pz✓
• B. σ1s<σ*1s< σ2s<σ*2s< π2py = π2pz<π2px
• C. σ1s<σ*1s< σ2s<σ*2s< π2px = π2pz< π2py
• D. σ1s<σ*1s< σ2s<σ*2s< π2py< π2pz< π2px

Explanation: This order represents the increasing energy levels of molecular orbitals as we move from the lower-energy sigma (σ) orbitals to the higher-energy pi (π) orbitals. In this order:The σls (sigma bonding orbital for the 1s electrons) is the lowest-energy molecular orbital.The σ*1s (sigma antibonding orbital for the 1s electrons) is slightly higher in energy than the σls orbital.The σ2s (sigma bonding orbital for the 2s electrons) is lower in energy than the σ*1s orbital.The σ*2s (sigma antibonding orbital for the 2s electrons) is higher in energy than the σ2s The п2ру (pi bonding orbital for the 2p electrons) is higher in energy than the σ*2s orbital.The П2рz (pi bonding orbital for the 2p electrons) is higher in energy than the п2ру orbital.The п₂рx (pi bonding orbital for the 2p electrons) is higher in energy than the П2рz orbital.Therefore, the correct answer is D) σls<σ1s< σ2s<σ2s< п2ру< П2рz<п₂рx.

Q83. The oxidation of pent-2-one with nascent oxygen gives:

• A. Propanal
• B. Propanoic acid
• C. Ethanoic acid
• D. Both B and C✓

Explanation: The reaction can be represented as follows:CH3CH2CH2COCH3 + O2 → CH3COOH + CH3CH2CH2COOHThus the products will be ethanoic acid and butanoic acid. So, correct answer will be ethanoic acid.

Q84. Four beakers containing ethanol, ethanal, propanone and phenol separately. Aqueous bromine was added to each beaker. A white ppt was produced in one beaker. This beaker contains.

• A. Ethanol
• B. Phenol✓
• C. Ethanal
• D. Propanone

Explanation: If bromine water is added to a solution of phenol in water, the bromine water/aqueous bromine is decolarized and a white precipitate is formed which smells of antiseptic. The precipitate is 2,4,6- tribromophenol.

Q85. To differentiate between the white ppt of AgCl and off-white ppt of AgBr we use:

• A. Dil.solution of NaOH
• B. Dil.solution of Pb(NO3)2
• C. Dil.solution of NH3✓
• D. Dil.solution of FeCl3

Explanation: The white precipitate of silver chloride dissolves in excess of ammonia, hypo solution and NaCN while bromide ions give a cream precipitate of silver bromide so the results can easily be distinguished.

Q86. CH3CH2 NH2+ C2H5 -C-C2 H5→ Product:

• A. Schiff’s salt
• B. Diazonium salt
• C. Amide
• D. Imine✓

Explanation: Based on the given reaction, the product formed is likely an imine, specifically an N-ethyl-N-(2-phenylethyl)imine. The correct answer is D. Imine

Q87. If the primer annealing temperature is increased to 94°C . What will happen ?

• A. Annealing
• B. Extension
• C. No Annealing✓
• D. Primer-dimer formation

Explanation: Primer annealing is a critical step in polymerase chain reaction or PCR. In this step, the primers bind to flanking sequences of the target DNA for amplification. If the primer annealing temperature is increased to 94°C non annealing occurs. At high temperature Non annealing occurs and the whole process is disturbed.

Q88. Choose acids that are showing leveling effect:i) HClO4 ii)HI iii) HCI iv) HF

• A. i & iv
• B. i, iii, & iv
• C. iii & iv
• D. i, ii, & iii✓

Explanation: Leveling effect or solvent leveling refers to the effect of solvent on the properties of acids and bases. The strength of a strong acid is limited ("leveled") by the basicity of the solvent. Similarly the strength of a strong base is leveled by the acidity of the solvent Thus H2O is a differentiating solvent for HI HCl HClO4.HF is a weak acid so it doesn't show levelling effect.

Q89. Which ion is stable in aqueous solution ?

• A. Sc3+
• B. Li2+
• C. Ba3+
• D. Na+✓

Explanation: In aqueous medium, due to extremely large hydration energy (energy evolved when a substance is hydrolysed), in aqueous medium, Li+ is more stable.

Q90. Colloidal particles can be separated by using:

• A. Ordinary filter paper
• B. Coarse filter paper
• C. Fine Filter paper
• D. Extremely fine filter paper✓

Explanation: Colloidal particles are small solid particles that are suspended in a fluid phase. Their size range is typically between 10nm. Colloidal particles can be separated by a centrifugation method using fine filter.

Q91. Consider the following reaction:2FeCl3 (aq) + 6KI(aq)→2Fe2(aq) + 6KCl(aq) + I2(s)Rate = [ FeCl3]1[KI]2 Choose the correct molecularity and the order of reaction respectively.

• A. 2 and 2
• B. 6 and 2
• C. 8 and 3✓
• D. 8 and 2

Explanation: This reaction involves eight molecules, but it has to be of third order because it is supposed to take place in two stages.FeCl3 + 2KI → FeI2 + 2KCl + Cl¯ (slow)2KI + 2Cl¯ → 2KCl + I2 (fast)The first stage is rate determining step, because it is slowest. The rate given by,Rate = d[I2]/d[t] = K[FeCl3][KI]2;So 1+2=3This indicates that the reaction is of third order and has 8 molecularity number.

Q92. The number of chiral centres in a molecule 5-bromo 3-chloro hexan-2-ol is/are:

• A. 1
• B. 3✓
• C. 2
• D. 5

Explanation: A chiral centre is an atom especially in an organic molecule that has four unique atoms or groups attached to it. To 3 carbons three different functional groups are attached. Therefore, 3 chiral centers are present.Note. To other adjacent carbon don't confuse the fact that 2 H are attached irrespective of different functional groups so they can’t be considered chiral.

Q93. Which group when attached to benzene will increase its reactivity:

• A. –NH4+✓
• B. –NH3
• C. –C≡N
• D. –COR

Explanation: Activating groups are Atoms or groups that make the benzene molecule more reactive by increasing the ring's electron density.The resonance structures suggest that the amino group increases the electron density only at ortho- and para-positions of the ring, making them more preferred to the electrophilic attack as they make the benzene more negative thus NH4+ can be used as activating group.

Q94. The compound which purely acidic character is:

• A. Mg (OH)2
• B. AI(OH)3
• C. Si (OH)4✓
• D. None of the above

Explanation: The compound where hydrogen is attached to the highly electronegative element is considered to be most acidic. Si(OH)4 is considered most acidic because Silicon is too similar in electronegativity to oxygen to form ionic bonds. Therefore, because silicon dioxide does not contain oxide ions, it has no basic properties and more acidic properties therefore It will react with strong bases to form silicate salts.

Q95. The compound which can be hydrolyzed by means of water is:

• A. CCI4
• B. SiCl4✓
• C. CH4
• D. None of the above

Explanation: Silicon can be hydrolysed by water because the silicon atom of silicon tetrachloride has energetically suitable vacant d-orbitals. Thus, it can accept a lone pair of electrons from the oxygen atom of a water molecule. Therefore, a silicon atom can expand its coordination number beyond four. Due to this reason SiCl4 is hydrolysed.Silicon tetrachloride (SiCl4) can undergo hydrolysis reaction with water to form orthosilicic acid (H4SiO4) and hydrogen chloride (HCl) gas.SiCl4 + 4H2O → H4SiO4 + 4HCl

Q96. Choose the correct statement about cycloakanes:

• A. Cyclopropane and cyclobutane are liquids at room temperature.
• B. Cycloalkanes are insoluble in ethanol and ether but soluble in water.
• C. Their melting and boiling points show a gradual increase with increases molecular weight.✓
• D. Both (B) & (C) are correct

Explanation: The longer the alkane gets (higher molecular weight), the more intermolecular forces are present (London Dispersion), and this increases the melting and boiling points therefore as cycloaljanes increase the chain the intermolecular forces increase more energy is required to break their bonds.

Q97. Which one is a strong nucleophile:

• A. C6 H5O
• B. H-O-✓
• C. NH3
• D. C2 H5 O-

Explanation: Nucleophilicity increases as the density of negative charge increases. An anion is always a better nucleophile than a neutral molecule, so the conjugate base is always a better nucleophile. A highly electronegative atom is a poor nucleophile because it is unwilling to share its electrons. A has ring system so increased charge density thus stronger nucleophile. H-O- is a strong nucleophile as it has a negative charge and a small size, which allows it to easily donate its lone pair of electrons to form a bond with a positive or electrophilic atom or group.

Q98. In movies during the fight, a blood-red solution is used as artificial blood. Which of the following complex ions is used for this solution?

• A. [Fe(H2 O)6 ]+2
• B. [Cu(NH3 )4 (H2 O)2 ]+2
• C. [Fe (SCN) (H2 O)5 ]+2✓
• D. [Fe(H2 O)6 ]

Explanation: [Fe (SCN) (H2O)5 ]+2 is used as artificial blood.

Q99. The compound which can form hydrogen bond with water is:

• A. CH3–O-CH3
• B. CH3 –CH2 –OH✓
• C. CH3 –CH2–NH2
• D. None of the above.

Explanation: Option B contains OH that can interact with the water to form a hydrogen bond with water. Hydrogen bonding occurs when hydrogen has a covalent bond to an atom that is more electronegative than it. The more electronegative atom pulls the shared electrons unequally towards it, creating a polar bond.

Q100. The compound with most exothermic lattice energy is:

• A. CaCl2
• B. K2O
• C. CaO✓
• D. BaCl2

Explanation: CaO has higher lattice energy because the lattice energy increases when the charge on the atom increases. Since the size of the calcium is smaller therefore it has higher lattice energy.

Q101. The less energetic and more stable compound among the following is:

• A. Cyclobutane
• B. Hex-1-ene✓
• C. Cyclopropane
• D. Propene

Explanation: Hex-1-ene is more stable because the stability of unsaturated hydrocarbons like nitriles, alkenes effects with hyper conjugation. Hence as the number of alkyl groups on double bonded carbon atoms increases, hyper conjugation increases which stabilizes the molecule and it is unreactive and it is less energetic due to strong carbon double bonds.

Q102. Amorphous solids are made by fusing silicates with:

• A. Boric acid
• B. Aluminum oxide
• C. Phosphorus pent oxide
• D. All of the above✓

Explanation: Amorphous solid, any noncrystalline solid in which the atoms and molecules are not organized in a definite lattice pattern. Such solids include glass, plastic, and gel. amorphous solid. It is made by fusing silicate with boric acid,aluminium oxide and phosphorus pentoxide all mixed together.

Q103. What is the product when chlorine gas is passed over element silicon in powdered state and heated it produce colorless liquid having the formula?

• A. SiCl2
• B. SiCl4✓
• C. Si2CI3
• D. SiCl

Explanation: When chlorine gas is passed over powdered silicon and heated, it produces silicon tetrachloride (SiCl4), which is a colourless liquid.The balanced chemical equation for this reaction is:Si(s) + 2C12(g) → SiCl4(1)Therefore, the formula of the colourless liquid produced is SiCl4, which is silicon tetrachloride. Thus, the correct answer is option B: SiCl4.

Q104. Compound resistant to thermal decomposition is:

• A. Li2CO3
• B. NaNO3
• C. Ba(NO3)2
• D. Na2CO3✓
• E. Non

Explanation: Na₂CO₃ is highly stable and resists decomposition even at high temperatures (above 1600°C). It remains intact under typical heating conditions.Ba(NO₃)₂, NaNO₃, and Li₂CO₃ decompose at relatively low to moderate temperatures:Ba(NO₃)₂ decomposes around 500°C.NaNO₃ decomposes around 380°C.Li₂CO₃ decomposes around 600°C

Q105. If CO2 level increase from the normal level, what will happen?

• A. Decrease in sea level
• B. Increase in sea level✓
• C. Longer winter season
• D. Daytime will increase

Explanation: If CO2 level increases than normal as the world warms due to greenhouse gases carbon dioxide included waters heat up and expand, causing sea levels to rise. The researchers found that the natural relationship displays a strong rise in sea level for CO2 increase from 180 to 400 parts per million, peaking at CO2 levels close to present-day values. The increased percentage of carbon-dioxide will cause the greenhouse effect, i.e. it will not allow the hot rays of the sun to escape from the atmosphere after reflection once they enter the earth's atmosphere, thereby increasing the temperature of the earth, ice on mountains will melt and the water level will rise.

Q106. Which compound will undergo substitution reaction faster than benzene ?

• A. Nitrobenzene
• B. Benzoic acid
• C. Benzaldehyde
• D. Phenol✓

Explanation: Option "a) Nitrobenzene," "b) Benzoic acid," and "c) Benzaldehyde" do not have electron-donating groups like the hydroxyl group in phenol. Instead, they possess electron-withdrawing groups (nitro group in nitrobenzene, carboxyl group in benzoic acid, and carbonyl group in benzaldehyde) that deactivate the benzene ring toward electrophilic substitution reactions. This electron-withdrawing effect reduces the reactivity of these compounds compared to benzene.In summary, "d) Phenol" will undergo substitution reactions faster than benzene due to the activating effect of the hydroxyl group on the benzene ring.

Q107. The IUPAC name of the compound given below:

• A. m-nitro benzoic acid
• B. o-nitro benzene methanoic acid✓
• C. o-nitro benzoic acid
• D. None of the above

Explanation: When two functional groups are next to each other in a benzene ring, we call them ortho group or o-group. Thus the compound is named as ‘o-nitro benzene methanoic acid’

Q108. Coagulation of proteins may be caused by:

• A. Heat
• B. Change in pH
• C. Heavy metal salts✓
• D. All of the above

Explanation: Heavy metal salts interact with proteins causing a change in their tertiary structure which leads in the denaturation of protein

Q109. What is the product of the Kolbe’s electrolysis of sodiumethanoate?

• A. Ethane✓
• B. Ethanol
• C. Ethene
• D. Ethyl ethanoate

Explanation: Kolbe’s electrolysis of sodium ethanoate (CH₃COONa)produces ethane (C₂H₆) at the anode via decarboxylation.

Q110. Chlorine gas dissolves in water to some extent to give:

• A. Yellow Colored solution
• B. Greenish Colored solution✓
• C. Bluish Colored solution
• D. Colorless solution

Explanation: Chlorine gas dissolves in water, forming a greenish solution called perchloric acid.

Q111. Ka values of some compound are given below, select the correct order of acidic strength:i.H2O ⇌H++OH-Ka=1x10-14 ii. ROH⇌RO-+H+Ka=1x10-18 iii. RCOOH⇌RCOO-+H+Ka=1x10-5 iv.C6H5OH⇌C6H5O-+ H+Ka=1x10-10

• A. ROH> H2O> C6H5OH>RCOOH
• B. C6H5OH > H2O> ROH > RCOOH
• C. RCOOH > C6H5OH > H2O > ROH✓
• D. RCOOH > ROH > C6H5OH > H2O

Explanation: The increasing strength of acidities is as follows; carboxylic acids, phenols, water and then ethanol. Students should know that carboxylic acids have two electronegative atoms which make the carboxylate anion stable whereas ethanol has positive inductive effect due to the presence of alkyl groups so it is the least acidic. This order is only followed by option C which is the answer

Q112. The compound which cannot be hydrolyzed by water is

• A. CH3–CH2–C–Br
• B. CH3–C–O–C– CH3
• C. CH3– CH2–C–NH2
• D. None of the above✓

Explanation: All of the above compounds can be hydrolyzed by water to split into 2 smaller molecules so option D is correct

Q113. KOH (alcoholic) + CH3 (CH3) 2 CH2Br (1), The reactants in the condition given will undergo:

• A. Nucleophilic substitution reaction
• B. Elimination reaction✓
• C. Nucleophilic addition
• D. None of the above

Explanation: It should be noted that whenever the reagent is alcoholic / ethanolic KOH or NaOH, the reaction that follows is elimination

Q114. Phosphorus (white) catches fire in air and burns with the formation of white smoke the product formed is:

• A. Phosphoruss (iii) oxide
• B. Phosphoruss (v) oxide
• C. Phosphorus (ii) oxide
• D. Both (A) & (B)✓

Explanation: When white phosphorus burns in air, it undergoes a slow combustion reaction to form phosphorus (I) oxide, which is also known as phosphorus monoxide or phosphorus(I) oxide. This compound has the chemical formula P2O and is a white crystalline solid that sublimes at high temperatures. The balanced chemical equation for the reaction is:4P (s) + 5O2 (g) → 2P2O (s)In addition to phosphorus (I) oxide, white phosphorus also reacts with oxygen to form phosphorus (V) oxide, which is also known as phosphorus pentoxide or phosphoric anhydride. This compound has the chemical formula P4O10 and is a white crystalline solid that is highly hygroscopic. The balanced chemical equation for the reaction is:P4 (s) + 5O2 (g) → P4O10 (s)Therefore, the correct answer to the question is option D) Both (A) & (B).

Q115. Coordination number six complex having d2Sp3 hybridization exist in:

• A. Tetrahedral shape
• B. Square planar shape
• C. Trigonalbipyramidal shape
• D. Octahedral shape✓

Explanation: Tetrahedral and Square planar have 4 bonding pairs, trigonal bipyramidal = 5 coordination number whereas octahedral = 6 coordination number so option D is correct

Q116. What type of hybridization is/are present in Hex-4-ene 1-yne:

• A. Sp2
• B. Sp
• C. Sp and Sp2
• D. Sp. Sp2. Sp3✓

Explanation: The first carbon atom has an sp hybridization, as it is involved in a triple bond with another carbon atom.The second and third carbon atoms have sp2 hybridization, as they are involved in a double bond with a carbon atom and a single bond with two other carbon atoms.The fourth carbon atom has sp hybridization, as it is involved in a triple bond with a carbon atom.The fifth carbon atom has sp2 hybridization, as it is involved in a double bond with a carbon atom and a single bond with two other carbon atoms.The sixth carbon atom has sp3 hybridization, as it is bonded to two other carbon atoms and two hydrogen atoms, resulting in a tetrahedral geometry.Therefore, the correct answer is D) sp, sp2, sp, sp2, sp, sp3. Explanation is given below.

Q117. In Saturated fatty acids more hydrogen are not accommodated because of:

• A. Presence of single bonds between carbon atoms.✓
• B. Presence of Double bonds between carbon atoms
• C. Presence of Triple bonds between carbon atoms.
• D. Absence of bond between carbon atoms.

Explanation: Saturated fatty acids contain a single bond between the carbon atoms, this is a fact

Q118. Which of the following atoms in the given oxidation state have the highest electro negativity.

• A. Mo(ii)✓
• B. Mo(iii)
• C. Mo(v)
• D. Mo(vi)

Explanation: Students should learn the Mo(ii) has the lowest oxidation state and highest electronegativity.Compared to the other given oxidation states of Molybdenum, Mo(ii) has the highest electronegativity because the valence electrons are closer to the nucleus and experience a greater effective nuclear charge. This makes Mo(ii) more electronegative than Mo(iii), Mo(v), and Mo(vi), which have more valence electrons and a higher effective nuclear charge that is more distributed across the electron cloud. Molybdenum in the +2 oxidation state has the electronic configuration: [Kr] 4d5. The oxidation state with a completely filled 4d subshell (Mo(ii)) has relatively lower electronegativity than other oxidation states. When comparing the electronegativity of the same element in different oxidation states, the electronegativity generally decreases as the oxidation state increases.Therefore, among the given oxidation states, Mo(ii) would have the highest electronegativity.Students should learn the Mo(ii) has the lowest oxidation state and highest electronegativity

Q119. The existence of H22+is not possible because

• A. It would be disproportion
• B. It would be ratio active
• C. It violates the pauli exclusion principle
• D. No H-H bond would form✓

Explanation: H22+ cannot be formed as it will be a very unstable structure due to the fact that there would be no bond between H-H

Q120. Excess of Ag2CrO4 was dissolved in distilled water its solubility was found to be 1.3x10-4mol dm-3. What is the solubility product:

• A. Ksp=[1.3x10-4]2[1.3x10-4]
• B. Ksp=[2.6x10-4]2[1.3x10-4]✓
• C. Ksp=[1.3x10-8][1.3x10-4]
• D. Ksp=[1.3x10-8]2[1.3x10-4]2

Explanation: Explanation is given below.

Q121. A container is having mixture of gases, 20% ammonia, 30% hydrogen and 50% oxygen under 50 a.t.m pressure choose the correct partial pressure respectively

• A. 10 atm, 25 atm, 15 atm
• B. 10 atm, 15 atm, 25 atm✓
• C. 25atm, 10 atm, 15 atm
• D. 15 atm, 25 atm, 10 atm

Explanation: Simplify 20:30:50 to get 10:15:25To find the partial pressures of each gas, we need to calculate the pressure contributed by each gas assuming they are the only gas present in the container:Partial pressure of ammonia = 20% x 50 atm = 10 atmPartial pressure of hydrogen = 30% x 50 atm = 15 atmPartial pressure of oxygen = 50% x 50 atm = 25 atm

Q122. Which cation is unstable in aqueous solution?

• A. Sb3+
• B. Bi3+✓
• C. Sn3+
• D. Fe3+

Explanation: This is a fact Boron does not have a d orbital to stabilize its charge and thus is unstable as a cation in aqueous solution.This is a fact and should be memorized.

Q123. Choose the incorrect statement about corrosion:

• A. Corrosion cannot be eliminated completely
• B. Employing modern techniques corrosion can be completely eliminates.✓
• C. Corrosion process can be slowed down by certain methods.
• D. The presence of acidic oxide in the environment can accelerate the process of corrosion.

Explanation: Option B is correct as corrosion can be eliminated using modern techniques

Q124. AlBr3 which is used in the alkylation of benzene possesses the properties of:

• A. A catalyst
• B. A Lewis acid
• C. An electron deficient specie
• D. All of the above✓

Explanation: AlBr3 is used as a catalyst, it is a lewis acid i.e is an electron-pair acceptor therefore it is also an electron deficient species so option D is correct

Q125. Choose the True product of the following reaction?CH3C≡N+2H2O+HCl→

• A. CH3COOH +NH3
• B. CH3COOH +NH4Cl✓
• C. CH3COCl +NH3
• D. CH3CONH2

Explanation: Students should remember that nitriles react with aqueous HCl in a hydrolysis reaction to form the corresponding carboxylic acid and salt of anion so the correct option is B which gives us ethanoic acid and ammonium chloride (salt)

Q126. Which polyatomic anion is unstable in solution ?

• A. BO2-
• B. SnO32
• C. S2O34-
• D. MnO42-✓

Explanation: It is a fact and has to be learntThe correct answer is D) MnO42-.MnO42- is unstable in solution because it can disproportionate to form MnO4- and MnO2. This occurs in basic solution according to the following reaction:3MnO42- + 2H2O → 2MnO4- + MnO2 + 4OH-The other options (BO₂, SnO32, S2034-) are stable polyatomic anions in solution.

Q127. Alkene+O3→Ozonide “Zn+H2O”→Propanone+Propanal, The IUPAC name of alkene is:

• A. Hex-2-ene
• B. Hex-3-ene
• C. 2-methyl pent-1-ene
• D. 2-methyl pent-2-ene✓

Explanation: d) 2-methyl pent-2-ene:2-methyl pent-2-ene is a five-carbon alkene with a methyl group attached to the second carbon atom and the double bond located between the second and third carbon atoms. The reaction doesn't provide enough information.

Q128. Choose the molecule that could not be represented by single electronic structure formula:

• A. CH4
• B. H2O
• C. SO2✓
• D. O2

Explanation: C is the correct option as the electronic structure of the SO2 molecule is best represented as a resonance hybrid of two equivalent structures.

Q129. At standard conditions 45 liters of oxygen gas weight about 64 g, where as 45 liters of hydrogen weight only 4g. Which gas defuse faster ? Calculate how much faster.

• A. Hydrogen, 4O2
• B. Hydrogen, 2O2✓
• C. Oxygen, 8H2
• D. Oxygen, 3H2

Explanation: The balanced chemical equation for the reaction between oxygen gas and hydrogen gas is:O2 + 4H2 → 2H2OAccording to this equation, for every 1 mole of oxygen gas, 4 moles of hydrogen gas are consumed. Therefore, to compare the diffusion rates of oxygen gas and hydrogen gas in this reaction, we need to compare the rates of diffusion of 1 mole of oxygen gas with the rates of diffusion of 4 moles of hydrogen gas.The ratio of the rates of diffusion of 1 mole of oxygen gas to 4 moles of hydrogen gas is:Rate of diffusion(O2) / Rate of diffusion(4H2) = 1 / (4√(M(H2) / M(O2))) = 1 / (4√(2 g/mol / 32 g/mol)) = 1 / (4√(1/16)) = 1 / This means that oxygen gas will diffuse 2 times slower than 4 moles of hydrogen gas. Alternatively, we can express this ratio in terms of the number of molecules:Rate of diffusion(O2) / Rate of diffusion(8H2) = √(n(8H2) / n(O2)) = √(8 x 2 mol / 2 mol) = √(8) = 2.83This indicates that 8 moles of hydrogen gas will diffuse 2.83 times faster than 1 mole of oxygen gas. Therefore, the correct answer to the question is option B) Hydrogen, 4O2.

Q130. Arrange the following oxide of chromium in increasing acidic character:

• A. CrO> Cr2O3> CrO3
• B. CrO3> Cr2O3>CrO✓
• C. Cr2O3 >CrO>CrO3
• D. CrO3>CrO> Cr2O3

Explanation: The increasing acidic strength is in this order of oxidation state; Cr3+ > Cr2+ > Cr+1 As increasing oxidation state increases the acid strengt

Q131. Choose Mercaptans of the following:

• A. R–S–R
• B. R–S–H✓
• C. R–O–R
• D. R–O–H

Explanation: Mercaptans are organosulfur molecules composed of carbon, hydrogen, and sulfur. As only option B fulfills these demands, it is the correct option

Q132. Many hexaaqua complex ions can undergo reaction with water as given below[Fe(H2O)6]+2 aq + H2O⇌[Fe(H2O)5OH]+ + H3O+The reaction is classed as:

• A. Redox reaction
• B. Acid base reaction
• C. Substitution reaction
• D. Decomposition reaction✓

Explanation: The reaction is ‘decomposition’ as one mole of water is removed to form the hydronium ion

Q133. Propene reacts with hypochlorous acid to form

• A. CH3–CH–CH2O ⋮ ClOHCl
• B. CH3–CH–CH2Cl ⋮ OH✓
• C. CH3–CH2–CH2Cl ⋮ OH
• D. CH3–CH–CH2 ⋮ OH

Explanation: The reaction between propene and hypochlorous acid (HOCl) can be represented as follows:CH3CH=CH2 + HOCl → CH3CH(OH)CH2ClThe product formed is 2-chloropropan-1-ol (CH3CH(OH)CH2Cl), which has a hydroxyl (-OH) group attached to the carbon adjacent to the chlorine atom. Therefore, the correct answer is option B) CH3-CH-CH2CI: OH.

Q134. Which of the following radiations cannot cause excitation in the molecule ?

• A. Red Colour
• B. Green Colour
• C. Ultra Voilet
• D. None of the above✓

Explanation: The answer is D as all the mentioned radiations can excite molecules.All electromagnetic radiation, including red and green colours of visible light, have the potential to cause excitation in molecules, although the likelihood of excitation increases with higher-energy radiation such as ultraviolet (UV) and X-rays. Therefore, all the options given in the question can cause excitation in molecules to some extent, and hence the correct answer is D) None of the above.

Q135. 10.0 dm3 gas cylinder containing mixture of various gases 50cm3 of nitrogen gas is in the mixture what is the concentration of N2 gas in part per billion (ppb).

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

Explanation: Students should remember that a billion has 9 zeros so option C and D can be eliminated. Also that 1 dm³ = 1000 cm³ so 10 dm³ = 10,000 cm³ So the correct answer is option B i.e 50/10,000 x 109As it is numerical, it can have only one answer.

Q136. Consider the following reactionsi.C2H2 (g) +H2 (g)→C2H6 (g) ii.N2 (g)+3H2→2NH3(g)Choose the catalysts employed for the reaction.

• A. Ni for both reactions (i) and (ii)
• B. Fe2O3for both the reactions (i) and (ii)
• C. Ni for the reaction (i) and Fe2O3 for (ii)✓
• D. Fe2O3 for the reaction (i) and Ni(ii)

Explanation: Reaction I is hydrogenation and reaction II is Haber process. Students should remember that the catalyst for hydrogenation is Ni metal while Haber process uses Fe2O3

Q137. The Screening Effect is also called:

• A. Shielding effect✓
• B. Transition effect
• C. Intervening effect
• D. Electronic effect

Explanation: The screening effect is also known as the "shielding effect" If the electron shells are wider in space, the interaction between the nucleus and electrons reduces. The order of screening effect in the shells is as follows: S > p > o > f. Nuclear fission is one of the best examples of the screening effect.

Q138. Magnalium is an alloy of _.

• A. Magnesium and Lead
• B. Magnesium and Aluminium✓
• C. Aluminium and Zinc
• D. Aluminium and Mercury

Explanation: Magnalium is an alloy of aluminium with magnesium and small amounts of nickel and tin.

Q139. The range of projectile is the same for two angles which are mutually:

• A. Perpendicular
• B. Supplementary
• C. Complementary✓
• D. 270̇°

Explanation: Two angles are complementary if their sum is 90 degrees. As explained previously, the range equation involves sin2θ. Because sin(180° - 2θ) = sin2θ, the range will be the same for angles θ and (90° - θ), which are complementary.

Q140. A wave of amplitude 20mm has intensity Ix. another wave of the same frequency but of amplitude 5mm has intensity Iy. What is Ix/Ty?

• A. 2
• B. 4
• C. 16✓
• D. 256

Explanation: The intensity of a wave is proportional to the square of its amplitude. Therefore, if a wave has an amplitude of 20 mm and an intensity of I, and another wave has an amplitude of 5 mm and an intensity of I/4 (since the amplitude is one-fourth), then the ratio of their intensities is:I/(I/4) = 4INow, if another wave of the same frequency but of twice the amplitude (i.e., 40 mm) is considered, then its intensity would be:(40/20)^2 * I = 4ITherefore, the ratio of the intensity of this wave to the intensity of the 20 mm amplitude wave is:(4I)/(I) = 4Similarly, the ratio of the intensity of this wave to the intensity of the 5 mm amplitude wave is:(4I)/(I/4) = 16As it is numerical, it can have only one answer.

Q141. The resistance of a device is designed to change with temperature. What is the device?

• A. A light dependent resistor
• B. A potential divider
• C. A semiconductor diode
• D. A thermistor✓

Explanation: The resistance of a device thermistor is designed to change with temperature. The resistance of a device is designed to change with temperature. What is the device.

Q142. When will 1 C of charge pass a point in an electrical circuit?

• A. When 1A moves through a voltage of 1V
• B. When a power of 1W is used for 1s
• C. When the current is 5mA for 200s✓
• D. When the current is 10A for 10s

Explanation: The formula used is Q = I x t Putting in the values, we get 1C as charge when Option C is used.

Q143. A cell of internal resistance 2.0Ω and electromotive force (e.m.f) 1.5V is connected to a resistor of resistance 3.0Ω. What is the potential difference across the 3.0Ω resistor?

• A. 5V
• B. 1.2V
• C. 0.9V✓
• D. 0.6V

Explanation: Rtotal = Internal resistance of the cell + Resistance of the external resistorRtotal = 2.0Ω + 3.0ΩRtotal = 5.0ΩCalculate the current (I) flowing through the circuit using Ohm's law:I = (e.m.f) / (Rtotal )I = 1.5V / 5.0ΩI = 0.3A (amperes)Finally, calculate the potential difference (V) across the 3.0Ω resistor using Ohm's law:V = I * R (where I is the current and R is the resistance of the resistor)V = 0.3A * 3.0ΩV = 0.9V

Q144. In a stationary wave the distance between consecutive antinodes is 25cm. If the wave velocity is 300ms-1, then the frequency of the wave will be:

• A. 150 Hz
• B. 300 Hz
• C. 600 Hz✓
• D. 750 Hz

Explanation: Distance between two consecutive antinodes is half the wavelength. We know that f=V/wavelength so 300/0.5 equals to 600.

Q145. A stationary nucleus has nucleon number A. The nucleus decays by emitting a proton with speed “v” to form a new nucleus with speed u. The new nucleus and the proton move away from one another in opposite directions. Which equation gives “v” in terms of A and u?

• A. v=(A/4-1)u
• B. v=(A-1)u✓
• C. v=Au
• D. v=(A+1)u

Explanation: D P=v, N=u, AAccording to the law of conservation of momentum, P(initial)= P(final)Pi is zero because system is at rest but Pf is equal to the sum of momentum of nucleus and momentum of proton.If 1 proton is emitted then the atomic number is reduced by 1. Therefore,0=MnVn+MpVp0 =(A-1)u +1vPutting negative sign with v because the direction is opposite 0=(A-1)u -1V1V= (A-1)u

Q146. A person, travelling on a motorway a total distance of 200 km,travels the first 90 km at an average speed of 80 km/hr. Which average speed must be obtained for the rest of the journey if the person is to reach the destination in a total time of 2 hours 0 minutes?

• A. 110 km/hr
• B. 120 km/hr
• C. 122 km/hr
• D. 126 km/hr✓

Explanation: Average speed = total distance / total timeTime taken to travel first 90 km = 90/80=1.125 h = 1h 7.5 minFor the rest of the journey, Distance that needs to be travelled =200-90 = 110 km Time remaining =2h-1.125 h- 0.875 hAverage speed = total distance/ total time = 110 / 0.875 = 126 km/hAs it is numerical, it can have only one answer.

Q147. A object of mass “m” travelling with speed “v” has a head-on collision with another object of mass “m” travelling with speed “v” in the opposite direction, the object sticks together after the collision.What is the total loss of kinetic energy in the collision?

• A. 0
• B. 1/2mv2
• C. mv2✓
• D. 2mv2

Explanation: Since there are two equal masses travelling with the equal velocity. Therefore according to the law of conservation of kinetic energy;Kinetic energy of the system before collision is equal to the kinetic energy of the system after collision is zero because they stick together and comes at rest.So loss is,1/2mv2 + 1/2mv2=0 1⁄2(mv2+ mv2)=0 2/2mv2=0Mv2=0Therefore the loss in kinetic energy is mv2.

Q148. A value for the acceleration of free fall on Earth is given as (10+-2) m s-2. Which statement is correct?

• A. The value is accurate but not precise✓
• B. The value is both accurate and precise.
• C. The value is neither precise nor accurate.
• D. The value is precise but not accurate.

Explanation: The ‘true’ value of the acceleration of free fall is 9.81 m s-2.From the value given in the question, the acceleration of free fall can be from (10 –2 =) 8 ms-2 to (10 + 2 =) 12 ms-2.The true value (= 9.81 ms-2) lies within the range given by the uncertainty, and therefore the stated value is accurate. Precision deals with how small or large the uncertainty is. A precise set of measurements would have a small scatter of readings. Here, the value is not precise as the uncertainty is large

Q149. Which experimental technique reduces the systematic error of the quantity being investigated?

• A. Adjusting am ammeter to remove its zero error before measuring a current.✓
• B. Measuring several inter modal distance on a standing wave to find the mean inter modal distance
• C. Measuring the diameter of a wire repeatedly and calculating the average.
• D. Timing a large number of oscillation to find a period

Explanation: Systematic error is an error having a non-zero mean, so that its effect is not reduced when observations are averaged. Zero error is an example of systematic error. it cannot be reduced by taking the average rather it is reduced by changing the instrument or changing the procedure.A zero error is a systematic error. So adjusting an ammeter to remove its zero error before measuring a current.

Q150. A metal sphere of radius r is dropped into a tank of water. As it sink at speed v, it experience a drag force F given by F= krv, where k is a constant. What are the SI base units of k?

• A. kg m2s-1
• B. kg m2s-2
• C. kg m-1s-1✓
• D. kg ms-2

Explanation: The following is the solution:F=krv which is equal to F/rvk=F/rv=kgms-2/m.ms-1=kgm-1s-1.

Q151. A carnot engine working between 200k and 400k has a work output of 600 J per cycle. How much heat energy is supplied to the engine from the source of each cycle.

• A. 1400 J
• B. 1200 J✓
• C. 1700 J
• D. 1300 J

Explanation: T₁ =400kT₂-200kW=800JWe know efficiency=1-T2/T1-WW/Q=1-200/400=600/0.5=1200JAs it is numerical, it can have only one answer.

Q152. What happens when a charge is placed on a soap bubble?

• A. It collapse
• B. Its radius increases✓
• C. Its radius decreases
• D. None of the above

Explanation: When some charge is placed on a soap bubble then the radius of the bubble will increase. Firstly, the charge will be distributed uniformly on the surface of a bubble. Secondly, the bubble will expand because the charged particles uniformly distributed on it cause them to repel each other due to the electrostatic force.

Q153. When a car travelling with constant velocity passes a stationary observer, the observer hears a change in the frequency of sound emitted by the car. Which statement is correct ?

• A. The change in frequency is greater as a car moves away than as it approaches.
• B. The greater the speed of the car, the greater the change in observed frequency.✓
• C. The observed frequency is lower as the car moves toward the observer and higher as the car moves away from the observer
• D. The volume of the sound heard by the observer does not change as the car approaches.

Explanation: Wave speed is the distance a wave travels in a given amount of time, such as the number of meters it travels per second. Wave speed is related to wavelength and wave frequency by the equation: Speed = Wavelength x Frequency so as the speed increases the observed frequency also increases.

Q154. A parachutist is falling constant terminal velocity. Which statement is not correct?

• A. Gravitational potential energy is converted into kinetic energy of the air.
• B. Gravitational potential energy is converted into kinetic energy of the parachutist.✓
• C. Gravitational potential energy is converted into thermal energy of the air
• D. Gravitational potential energy is converted into thermal energy of the parachutist.

Explanation: Terminal velocity reaches when the force of gravity acting on the object is equal to the air resistance or viscous force of air on the body. Air resistance is a major factor contributing in a falling object to reach terminal velocity as it can easily contribute to the speed at which the body thus both kinetic energy and potential energy cannot be equated.

Q155. The time period of a simple pendulum is 2 seconds. If its length is increased by 4 times, then its period becomes:

• A. 16s
• B. 12s
• C. 8s
• D. 4s✓

Explanation: The formula for the period of a simple pendulum is: T = 2π √(L/g) Where: T is the period of the pendulum, L is the length of the pendulum, and g is the acceleration due to gravity. In this case, we have a pendulum with a period of 2 seconds. So, we can substitute these values into the formula: 2 = 2π √(L/g) Now, let's consider the length of the pendulum increased by 4 times. Let's call the new length L'. So, we have: T' = 2π √(L'/g) To compare the periods, we can divide the two equations: T' / T = (2π √(L'/g)) / (2π √(L/g)) Simplifying this equation, we get: T' / T = √(L'/g) / √(L/g) T' / T = √(L') / √L Since the length is increased by 4 times, we can write L' = 4L: T' / T = √(4L) / √L T' / T = 2√L / √L T' / T = 2 Therefore, the period of the pendulum becomes 2 times the original period. Since the original period is 2 seconds, the new period will be 2 * 2 = 4 seconds.

Q156. Work function for a certain surface is 3.3 ev. Minimum frequency, light must have in order to eject electron from surface will be:

• A. 8 x 1014 Hz✓
• B. 3.2 x 1015 Hz
• C. 4.8 x 1015 Hz
• D. 6.4 x 1015 Hz

Explanation: The correct option is A.To calculate the minimum frequency of light required to eject an electron from a surface, we need to use the formula:f = (W/E)where f is the minimum frequency, W is the work function, and E is the energy of a photon of light.Since the work function is given as 3.3 eV, we first need to convert it to joules using the conversion factor 1 eV = 1.6 x 10^-19 J:W = 3.3 eV x 1.6 x 10^-19 J/eV = 5.28 x 10^-19 JThe minimum energy of a photon required to eject an electron is equal to the work function, so we have:E = W = 5.28 x 10^-19 JNow we can plug in these values into the formula and solve for f:f = (W/E) = (5.28 x 10^-19 J) / (6.63 x 10^-34 J s) = 7.97 x 10^14 Hzwhich is approximately equal to 8 x 10^14 Hz. As it is numerical, it can have only one answer.

Q157. The units of planks constant are the same as that of :

• A. Angular Momentum✓
• B. Work
• C. Force
• D. Torque

Explanation: The unit of planck's constant is equivalent to that of angular momentum. Their dimensional formulas are the same but both physical quantities are not the same. Planck's constant gives the relation between energy and frequency

Q158. A radioactive substance has a half-life of 60 minutes. During 3 hours, the percentage of the material that decayed would be:

• A. 12.5%
• B. 87.5%✓
• C. 8.5%
• D. 25.1%

Explanation: 𝑁=𝑁0(1/2)𝑡𝑇1/21-1/No=1-(½)3*60/60=⅞⅞*100=86.5%.

Q159. Choose the correct arrangement of the various regions of the electromagnetic spectrum in terms of wave length.

• A. Ir>uv> visible > microwave > radio frequency
• B. Microwave >ir> visible >uv> radio frequency
• C. Radio frequency > microwave >ir> visible >uv✓
• D. Visible >ir>uv> microwave > radio wave

Explanation: Radio frequency > microwave >ir> visible >uvD. Visible >ir>uv> microwave > radio wave this is the correct arrangement of wavelength in the spectrum.

Q160. The acceleration of free fall on the Moon is one-six of that of Earth. On Earth, it takes time ‘t’ for a stone to fall from rest a distance of 2 m. What is the time taken for a stone to fall from rest a distance of 2 m on the Moon?

• A. 6 t
• B. T/6
• C. t√6✓
• D. t/√2

Explanation: Let the acceleration of free fall on Earth = gAcceleration of free fall on Moon = g16The stone is released from rest at a height of 2m.Initial velocity, u = 0. Distance, s = 2mEquation for uniformly accelerated motion: s = ut + ½ at2On Earth, the time taken is t 2=0+0.5g12Acceleration,g=4/12Now, consider the stone falling on the Moon. Let the time taken be tM. 2=0+0.5 (g/6) tM2Time tM = √(4/9)=√(24/4/12)) = ✓(6/12)=⅙As it is a numerical, it can have only one possible answer.

Q161. Before thunder, the hair stands on end. A hair with a mass of 0.50 ng and a charge of 1.0 pC is supported by a force other than the weight of the hair and the electric force. What is the electric field strength?

• A. 4.9 x 103 N C-1✓
• B. 4.9 x 106 N C-1
• C. 4.9 x 105 N C-1
• D. 4.9 x 109 NC-1

Explanation: The electric force is equal to the weight.Electric force = Weight Eq = mgElectric field strength E = mg / q {mass should be in kg.)E = [(0.50 μg) × (9.8 m/s²)] / (1.0 pC)Now, let's plug in the values and convert units if needed:1 μg = 10^-9 kg1 pC = 10^-12 CE = [(0.50 × 10^-9 kg) × (9.8 m/s²)] / (1.0 × 10^-12 C)E = [4.9 × 10^-9 kg m/s²] / (1.0 × 10^-12 C)E = 4.9 × 10³ N/CSo, the electric field strength is 4.9 × 10³ N/C.

Q162. Two lamps are connected in series to a 250 V power supply. One lamp is rated 240 V, 60 W, and the other rated 10 V, 2.5 W. Which statement most accurately describes what happens?

• A. Both lamps light at less than their normal brightness
• B. Both lamps light at their normal brightness✓
• C. Only the 240 V lamp lights
• D. The 10 V lamp blows

Explanation: Since One lamp is rated 240 V, 60 W This means that for the lamp to operate normally, there should be a p.d. across it.P=VICurrent flowing through the lamp P/V=60/240=0.25 The other lamp is rated 10 V, 2.5 WThis lamp operates normally when there is a p.d. of 10 V across it.Current flowing through the lamp = P/V-25/10=0.25 ASo, for normal operation, the same current of 0.25 A is required for both lamps.Since the lamps are connected in series, the same current would flow. So, both lamps light at their normal brightness. In the same way, the sum of p.d. across the 2 lamps is equal to 240 +10 = 250 V.

Q163. A tuning fork A produces 4 beats / second with another turning fork B of frequency 280 Hz. When fork A is loaded with a little wax, the beat frequency changes to 2. The frequency of fork A before loading is:

• A. 292 Hz
• B. 284 Hz✓
• C. 290 Hz
• D. 288 Hz

Explanation: Beat frequency is given by the equation; Beat frequency = f1-f2Whereas f1 is AAnd f2 is BSince the frequency of the B tuning fork is 280 Hz and the number of beats per second before applying wax is 4. Therefore,4-f1-280 F1-4+280 F1/A is 284Hz.As it is a numerical, it can have only one possible answer.

Q164. The sound waves of frequency more than 20 khz are termed as:

• A. Supersonic
• B. Audible
• C. Infrasonic
• D. Ultrasonic✓

Explanation: Ultrasonic waves are sound waves whose frequencies are higher than those of waves normally audible to the human ear. ultrasonics, vibrations of frequencies greater than the upper limit of the audible range for humans—that is, greater than about 20 kilohertz.

Q165. The refractive index is equal to the tangent of the angle of polarization. It is called:

• A. Brewster’s Law✓
• B. Malu’s Law
• C. Bragg’s Law
• D. Grimaldi’s Law

Explanation: Brewster's law gives a relationship for light waves stating that the maximum polarization (vibration in one plane only) of a ray of light may be achieved by letting the ray fall on the surface of a transparent medium in such a way that the refracted ray makes an angle of 90 with the reflected ray. So, the correct answer is option (A), i.e. Brewster's Law.

Q166. If x-component of a vector is √3 and y-component is 1, then the angle made by the vector along x-axis is:

• A. 60O
• B. 30O✓
• C. 45O
• D. 90O

Explanation: We find out the angle usingtan = x component/ycomponentso tan = √3/1 and then we inverse tan to find the angletherefore the angle = tan-1 (1/√3)= 30 degrees.As it is numerical, it can have only one possible answer.

Q167. In Young double slit experiment with sodium light, the slit are 0.589m apart. What is the angular width of the third maximum given λ=589nm

• A. sin-1(3x10-6)✓
• B. sin-1(3x10-8)
• C. sin-1(3x10-6)
• D. sin-1(3x10-8)

Explanation: Explanation is given below.Correct option is A)Using relation, dsinθ=nλ⇒sinθ= dnλFor third maximum ,n=3∴sinθ= d3π⇒sinθ= 0.5893×589×10 −9⇒sinθ=3×10 −6⇒θ=sin−1 (3×10 −6 )As it is numerical, it can have only one possible answer.

Q168. Which of the following waves cannot be polarized?

• A. Radio waves
• B. Ultrasound✓
• C. Ultraviolet
• D. X-rays

Explanation: "Ultrasound" waves are longitudinal in nature, hence they cannot be polarized.Only transverse waves like electromagnetic waves can be polarized.

Q169. When a ray of light enters a glass slit from air:

• A. Its wave length decreases✓
• B. Its wave length in creases
• C. Its frequency increases
• D. Its frequency decreases

Explanation: As the medium is dense, the speed decreases. The frequency has to remain constant therefore the wavelength decreases ( v = fλ)

Q170. Light of wave 500x10 -9 m falls normally on a plane diffraction grating having 8 x 10 +3 lines per cm. The minimum number of images seen is:

• A. 3✓
• B. 4
• C. 5
• D. 1

Explanation: Explanation is given below.The formula for the number of images formed by a diffraction grating is:nλ = d(sinθ + sinφ)where n is the order of the spectrum, λ is the wavelength of the light, d is the distance between the slits, θ is the angle between the incident beam and the normal to the grating, and φ is the angle between the diffracted beam and the normal to the grating.In this case, the wavelength of the light is λ = 500 x 10^-9 m, the distance between the slits is d = 1/8000 m = 1.25 x 10^-4 m, and the incident beam falls normally on the grating so θ = 0.To find the value of φ for the first order spectrum, we can set n = 1 in the above formula and solve for sinφ:sinφ = λ/d = (500 x 10^-9)/(1.25 x 10^-4) = 0.004Taking the inverse sine of this value, we get:φ = sin^-1(0.004) = 0.23°For the first order spectrum, there will be a bright spot at an angle of 0.23° on either side of the central maximum, giving a total of three images. Therefore, the minimum number of images seen is 3.So, the answer is 3.As it is a numerical, it can have only one possible answer.

Q171. The speed of sound in air at NTP is 300 ms-1. If the air pressure become 4 times; then the speed of the sound will be:

• A. 150 s-1
• B. 300 s-1✓
• C. 600s-1
• D. None

Explanation: The speed of sound in air at NTP is a constant value i.e 300 ms-1 (it does not change) The speed of sound in a gas is independent of its pressure

Q172. Standing waves are produced in 10 m long stretched string. If the string vibrates in 5 segments and wave velocity is 20 ms-1, its frequency is:

• A. 2 Hz
• B. 4 Hz
• C. 5 Hz✓
• D. 10 Hz

Explanation: (Remember that node to node is half A) so λ= 10/5 and then λ = 2x2=4mThen we find out the frequency using the formula v = fλ ie 20 = f(4) and f = 20/4 = 5 Hz As it is numerical, it can have only one possible answer.

Q173. A particle executes SHM along a straight line. Its amplitude is A. The potential energy of the particle is equal to the kinetic energy when the displacement of the particle from the mean position is:

• A. Zero
• B. ±A/2
• C. ±A/√2✓
• D. 2A

Explanation: When the potential energy is equal to the kinetic energy, we have:(1/2)kx^2 = (1/2)mv^2x^2 = (mv^2)/kv^2 = kx^2/mSubstituting v^2 into the expression for K, we have:K = (1/2)mv^2 = (1/2)m(kx^2/m) = (1/2)kx^2Thus, when the potential energy is equal to the kinetic energy, we have:2K = 2U2(1/2)kx^2 = (1/2)kA^2x^2 = A^2/2x = ±A/√2Therefore, the displacement of the particle from the mean position when the potential energy is equal to the kinetic energy is ±A/√2.lAs it is numerical, it can have only one possible answer.

Q174. In S.H.M, the fraction of kinetic energy to total energy when displacement is one-half of the Amplitude is

• A. 1/8
• B. 1/2
• C. 1/4
• D. 3/4✓

Explanation: Correct option is D)In case of SHMKE= 1/2​ mω^2 (a ^2 −x ^2 ) and at x=a/2KE= 1/2 mω ^2 [a^2 −(a/2)^2 ]= 3/4​ [ 1/2​ mω^2 ^ 2 ]Total energy = 1/2​ mω^2 a^2 ∴ Fraction of total energy= KE/Total energy​ = 3/4​ [1​/2 mω^2 a^2 ] = 3/4​ 1/2mωa^2As it is numerical, it can have only one answer.

Q175. Laplace corrected Newton’s formula for the velocity of sound in gas because the sound propagates:

• A. As longitudinal
• B. Adiabatically✓
• C. Isothermally
• D. Under isobaric conditions

Explanation: The transfer of energy is in the form of work done, during sound propagation so it is an adiabatic process

Q176. Two bodies are dropped from different heights h1 and h2. There ratio of the times taken by them to reach the ground will be:

• A. h22:h12
• B. h1 :h 2
• C. √M1=√M2✓
• D. None of the above

Q177. A bullets of mass m moving with a velocity v is fired into a large wooden block of mass M. If the bullet remains embedded in the wooden block, the velocity of the system will be:

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

Explanation: Since there is no extra force other than the action and reaction force so the linear momentum should be conserved.Suppose the system moves with velocity Vthen momentum before collision is mv and that after collision will be (M+m)VEquating both we get mv=(M+m)V or V= m/m+M* v As it is numerical, it can have only one answer.

Q178. A particle is moving with a constant speed a long a straight line. A force is not required to:

• A. Increased speed
• B. Decreased the momentum
• C. Change the direction
• D. Keep it moving with uniform velocity✓

Explanation: According to Newton's law if a body is at rest or moving at a constant speed in a straight line, it will remain at rest or keep moving in a straight line at constant speed unless it is acted upon by a force so option D is correct

Q179. Choose the anisotropic behavior

• A. Coefficient of thermal expansion✓
• B. Lattice energy
• C. Viscosity
• D. Infrared spectroscopy

Explanation: Anisotropy is the property of a material which allows it to change or assume different properties in different directions so the correct option is A i.e coefficient of thermal expansion as there are 3 coefficients i.e for volume, area and linear expansion

Q180. A circular disc of mass M and radius R is rotating about it’s with uniform speed v. Its kinetics energy is:

• A. Mv2
• B. ½ Mv2
• C. ¼ Mv2✓
• D. 1/8 Mv2

Explanation: The kinetic energy of the rotating disc can be calculated as:KE = (1/2) I ω^2where I is the moment of inertia and ω is the angular velocity.For a uniform circular disc rotating about its centre,I = (1/2) M R^2andω = v/RSubstituting these values in the formula for kinetic energy, we get:KE = (1/2) (1/2) M R^2 (v/R)^2Simplifying, we get:KE = (1/4) M v^2Therefore, the kinetic energy of the rotating disc is (1/4) M v^2.As it is numerical, it can have only one possible answer.

Q181. The moment of inertia of an object does not depend upon:

• A. Mass of an object
• B. Mass of distribution
• C. Angular velocity✓
• D. Axis of rotation

Explanation: The moment of inertia Iof an object is a measure of its resistance to changes in angular velocity. It depends on the mass of the object and how that mass is distributed around the axis of rotation, but it is not influenced by the current angular velocity. Therefore, option c is correct.

Q182. A body of mass 10 kg is hanging from a spring inside a lift. If the lift falls with an acceleration 10ms-2 then what will be the reading of spring balance:

• A. Zero✓
• B. 2.5 kg
• C. 5 kg
• D. 10 kg

Explanation: The reading of the spring balance in this case would be zero.When the lift falls with an acceleration of 10 m/s^2, the weight of the body remains the same (i.e., 10 kg) but the apparent weight of the body changes. The spring balance measures the apparent weight of the body, which is given by the difference between the weight of the body and the upward force exerted by the spring on the body. In this case, the upward force exerted by the spring is equal to the force of gravity acting on the body (i.e., its weight) plus the force required to provide the apparent weight due to the acceleration of the lift. This total force cancels out the effect of gravity, making the apparent weight zero.Therefore, the reading of the spring balance would be zero in this case.

Q183. A man walk for some time with velocity v due east. Then he walks for same time with velocity v due north. The average velocity for man is:

• A. 2v
• B. √2v
• C. v
• D. v/√2✓

Explanation: c) v/√2 This option suggests that the average velocity of the man is v. This is the correct answer. The average velocity of the man is equal to his total displacement divided by the total time taken. Since the man walks with velocity v due east and then with velocity v due north, his displacement is the diagonal distance between his initial and final positions, and the magnitude of this displacement is v. Dividing this displacement by the total time taken gives the average velocity, which is v/√2 .

Q184. The Sum of 2 forces acting at a point is 16N. If the resultant force is 8N and its direction is perpendicular to minimum force, then the force is:

• A. 6N and 10N✓
• B. 8N and 8N
• C. 4N and 12N
• D. None of them

Explanation: Correct option is A)A+B=16...(1)Tanα = Bsinθ/A+Bcosθ = tan90Thus, A+Bcosθ = 0 ⇒cosθ = − A/B ...(2)We also have: 8= √A^2 +B^2 +2ABcosθ ...(3)Solving these we get, A=6N and B=10NAs it is numerical, it can have only one possible answer.

Q185. A boy walks to his school at a distance of 6km with a speed of 3km/h and walks back with a constant speed of 2km/h. His average speed for round trip in km/h is:

• A. 2.5
• B. 2.4✓
• C. 5
• D. 2.3

Explanation: We find out the average speed by using2v1v2/(v1+v2) = 12/5 = 2.4 km/h

Q186. How much kinetic energy will be gained by an (alpha) particle ion going from a point at 70 V to another point at 50 V ?

• A. 40 eV✓
• B. 40 KeV
• C. 40 MeV
• D. Zero

Explanation: A K.E is equal to EPE i.e qAV so 2e x 20V= 40 eVAs it is numerical, it can have only one possible answer.

Q187. The potential of the two plates of a capacitor are +10 V and -10 V the charge on one of the plates is 40C . The capacitance of the capacitor is :

• A. 2 F✓
• B. 4 F
• C. 0.5 F
• D. 0.25 F

Explanation: The potential difference across the parallel plate capacitor is 10V- (-10)=20VCapacitance= Q/V = 40/20 = 2 FaradAs it is numerical, it can have only one possible answer.

Q188. In a simple electrical circuit the current in a resistor is measured as (2.50 +_ 0.05) mA. The resistor is marked as having a value of 4.7 _+2%. If these value where used to calculate the power dissipated in the percentage uncertainty in the value obtained ?

• A. 2%
• B. 4%
• C. 6%✓
• D. 8%

Explanation: First we find out the % uncertainty in current (0.05)/2.5 x 100 = 2%. Then we note the formula of power dissipated is 12 x R so the = percentage uncertainty has to be added i.e (2+2)+2=6%As it is numerical, it can have only one possible answer.

Q189. In a stream lined flow the velocity of the liquid in contact with the containing vessel is:

• A. Zero
• B. Minimum but not zero✓
• C. Large
• D. Peripheral

Explanation: b) Minimum but not zeroThis option suggests that the velocity of the liquid in contact with the containing vessel is the minimum but not zero. This is the correct answer. In streamlined flow, the velocity of the fluid in contact with the vessel is minimum compared to the velocity of the fluid away from the boundaries. The velocity increases as we move away from the boundary and towards the center of the flow.

Q190. Eight drops of water, each radius 2mm are falling through air at a terminal velocity of 8cms-1. If they coalesce to form a single drop the terminal velocity of the combined drop will be:

• A. 8 cms-1
• B. 16 cms-1
• C. 24 cms-1
• D. 32 cms-1✓

Explanation: Explanation is given below.Let the radius of bigger drop is R and smaller drop is r then4/3πR^3 = 8×4/3×πr^3or R=2r ....(i)Terminal velocity,vt = 2 r^2(ρ−σ)g/9η​vt ∝ r^2 v’/v = R^2 / r^2 =(2r/r)^2 =4 (Using (i))or v′ =4v=4×8=32cms^−1As it is numerical, it can have only one possible answer.

Q191. The frequency of a second’s pendulum is :

• A. 1 Hz
• B. 2 Hz
• C. 5Hz
• D. None of the above.✓

Explanation: A seconds pendulum has time period of 2 seconds and frequency of 0.5 Hz

Q192. The Ratio of electro force between two protons to that between two electrons is of the order of:

• A. 1042
• B. 1039
• C. 1036
• D. 1✓

Explanation: d) 1This option suggests that the ratio of the electrostatic force between two protons to that between two electrons is 1. This is the correct option. As explained earlier, the magnitude of the electrostatic force between charged particles is directly proportional to the product of their charges and inversely proportional to the square of the distance between them. Since protons and electrons have equal and opposite charges, the magnitude of the force between two protons is the same as the force between two electrons, and their ratio is 1:1.

Q193. When 1012 electrons are received from a neutral metal sphere. The charge on the sphere becomes:

• A. 0.16uc✓
• B. -0.16uc
• C. 0.32uc
• D. -0.32uc

Explanation: The formula used is q (charge) = n x e so q = 1012 x 1.6x10-19 =1.6x10-7=0.16 ucAs it is numerical, it can have only one possible answer.

Q194. An electric charge in an accelerated motion produce:

• A. An electric field only
• B. A magnetic field only
• C. Electromagnetic radiation only
• D. All of the above✓

Explanation: Accelerating charges produce changing electric and magnetic fields. Changing electric fields produce magnetic fields and changing magnetic fields produce electric fields. This interplay between induced electric and magnetic fields leads to propagating electromagnetic waves.

Q195. A bomb explodes on the moon. How long will it take for the sound to reach the earth:

• A. 10 sec
• B. 1000 sec
• C. 1 day
• D. None of the above✓

Explanation: When a bomb explodes on the moon- due to the vacuum there is no medium for the propagation of sound and hence it cannot reach the earth

Q196. A body of mass 2kg collides with a wall with speed 100 m s-1 and rebounds with the same speed the force exerted on the wall is 2 x 104 N. The time of contactis:

• A. 1/50 Sec✓
• B. 1/25 Sec
• C. 1/60 Sec
• D. 1 Sec

Explanation: F=mv/t2 x 104 N =2*(100-(-100))/tt=1/50 s

Q197. An engine pumps out 40kg of water in second. The water comes out of vertically upward with a velocity of 3 ms-1, the power of engine in kilowatt is:

• A. 1.2 kW✓
• B. 12kW
• C. 120kW
• D. 1200kW

Explanation: Students should remember the formula of power i.e Force x speed So power = (mass x g) x speed assume g = 10] Power = (40 x 10) x 3 = 1200 W or 1.2 kW

Q198. Two boys weighting in the ratio 4:5 goes up stair taking time in the ratio 5:4. The ratio of their power is:

• A. 1
• B. 16/25✓
• C. 25/16
• D. 4/5

Explanation: Power of first boy / Power of second boy ∝ (Weight of first boy / Weight of second boy) × (Time taken by second boy / Time taken by first boy)Power of first boy / Power of second boy ∝ (4/5) × (4/5) = 16/25

Q199. Select the most suitable synonym for the given word:BASHFUL

• A. Timid✓
• B. Susceptible
• C. Bold
• D. Invulnerable

Explanation: Bashful means to be shy and unwilling to attract attention, similarly timid also means to be shy.

Q200. Select the most suitable synonym for the given word:CRUDELY

• A. Roughly✓
• B. Sporadically
• C. Accurately
• D. Regularly

Explanation: Crude is another word to describe rude, offensive behaviour, similar to rough.