Balochistan Mdcat 2023 — Solved Past Paper with Answers

Q1. Choose the correct sentence:

• A. Work all day, my father doesn't have much time to spare.
• B. Working all day, my father don't have much time to spend.
• C. Working all day, my father doesn't have much time to spend.✓
• D. Working all day, my father doesn't have much time to spent.

Explanation: "Working" is the participle, and "doesn't" agrees with "father." "Spend" is correct, not "spent."

Q2. Neither she nor _ am guilty. Complete the sentence with the correct pronoun.

• A. Us
• B. We
• C. They
• D. Me✓

Explanation: The correct answer is me because in the phrase 'Neither she nor _ am guilty,' the verb 'am' is used, which aligns with the subject pronoun 'I.' The structure 'neither...nor' requires that the pronoun and verb agree with the closest noun, which in this case is 'she.' Since 'she' is singular and the verb form is 'am,' the correct pronoun to complete the sentence is 'me,' as it reflects the speaker's involvement in the guilt.

Q3. Choose the sentence that follows the correct adjectives order.

• A. A beautiful blue sailing boat.✓
• B. A blue beautiful sailing boat.
• C. A beautiful sailing blue boat.
• D. A blue sailing beautiful boat.

Explanation: The correct order is opinion, size, age, shape, color, origin, material, and purpose

Q4. Use an appropriate article:He is extremely alert and watchful like _ cat.

• A. A✓
• B. An
• C. The
• D. No article required

Explanation: "A cat" is the correct choice because the sentence refers to any cat in general, not a specific one.

Q5. "I will not tolerate his rudeness."Choose the sentence that has the same meaning as the above sentence.

• A. I cannot put up for his rudeness.
• B. I cannot put up with his rudeness.✓
• C. I cannot put up to his rudeness.
• D. I cannot put up by his rudeness.

Explanation: "Put up with" means to tolerate, which correctly conveys the meaning of the original sentence.

Q6. The boys on the opposite side made me _ the bird.

• A. To kill
• B. Kills
• C. Kill✓
• D. Killed

Explanation: "Made" is a causative verb, so the correct structure is "made me kill."

Q7. Choose the sentence with correct semicolon placement.

• A. The pen was expensive, still I bought it.
• B. The pen was expensive still; I bought it.
• C. The pen was expensive still I bought it.
• D. The pen was expensive; still I bought it.✓

Explanation: A semicolon correctly separates two independent clauses.

Q8. Choose a synonym for the underlined word;Vicissitudes of life are unexpected; nothing remains the same.

• A. Changes✓
• B. Evils
• C. Mistakes
• D. Rules

Explanation: "Vicissitudes" refer to the ups and downs or changes in life.

Q9. You will have to catch the morning flight, so you _ better get ready.

• A. would
• B. may
• C. should
• D. had✓

Explanation: "Had better" is a strong recommendation meaning "it is advisable."

Q10. The most appropriate antonym for "abridge" is:

• A. Condense
• B. Lengthen✓
• C. Shorten
• D. Reduce

Explanation: "Abridge" means to shorten, so its opposite is to lengthen. Hence, "lengthen" is the correct answer.

Q11. Which of the following is correct?

• A. Forty years seems a long time.✓
• B. Forty years seem long time.
• C. Forty years seems long time.
• D. Forty years seem a long time.

Explanation: "Forty years" is considered a singular unit of time, so "seems" (singular verb) is correct.

Q12. A boy is waiting for you for a long time. In this sentence, the word 'boy' is?

• A. Proper Noun
• B. Common Noun✓
• C. Abstract Noun
• D. Collective Noun

Explanation: "Boy" is a common noun as it refers to any boy, not a specific one.

Q13. I _ from college by this time next year and will be looking for a job.

• A. Will graduate
• B. Graduated
• C. Will be graduating
• D. Will have graduated✓

Explanation: "Will have graduated" indicates completion before a specified future time.

Q14. The most appropriate word to be filled in is:The melody is _.

• A. Plaintive✓
• B. Baffling
• C. Blissful
• D. Green

Explanation: "Plaintive" means sad or mournful, which fits well with "melody."

Q15. The temperature at which an inactive enzyme regains its function is called:

• A. Maximum Temperature
• B. Minimun Temperature
• C. Favourable Temperature
• D. Optimum Temperature✓

Explanation: Correct, as it is the temperature at which an enzyme shows maximum activity and can regain function after temporary inactivation.

Q16. Dominance is the physiological effect of an allele over its partner allele occupying the:

• A. Same locus on same chromosome
• B. Different locus on same chromosomes
• C. Same locus on respective homologue✓
• D. Different locus on respective homologue

Explanation: Alleles are located at the same position on homologous chromosomes, and one may be dominant over the other.

Q17. Which of the following is a product of neurosecretory cells?

• A. Aldosterone
• B. Thyroxine
• C. Corticosterone
• D. Vasopressin✓

Explanation: Vasopressin is secreted by the hypothalamus and stored in the posterior pituitary, making it a neurohormone. Vasopressin increases water retention by the kidneys, primarily in the collecting ducts, to prevent dehydration and concentrate urine.

Q18. Lipoprotein particles make membranes containing various enzymes and F1 particles in:

• A. Crista✓
• B. Cisternae
• C. Forming face
• D. Matrix

Explanation: Correct, as the inner mitochondrial membrane forms cristae, which house the F1 particles involved in ATP synthesis.

Q19. Which of the following viruses is classified as an ssDNA virus?

• A. Diarrhea virus
• B. Mild rash virus✓
• C. Rubella virus
• D. Smallpox virus

Explanation: Parvovirus B19, which can cause mild rashes and conditions like fifth disease in children, is a single-stranded DNA virus.

Q20. Catastrophism was explained by:

• A. Wallace
• B. Cuvier✓
• C. Malthus
• D. Darwin

Explanation: Correct, because Georges Cuvier proposed catastrophism, which suggests that Earth's history has been shaped by sudden, short-lived, violent events.

Q21. Plasma membrane is:

• A. Biradially Symmetrical
• B. Asymmetrical✓
• C. Radially Symmetrical
• D. Bilaterally Symmetrical

Explanation: Correct, because the lipid bilayer of the plasma membrane has different compositions on its inner and outer surfaces

Q22. How many valves are present in a human heart?

• A. 2
• B. 4✓
• C. 3
• D. 6

Explanation: Correct, as the human heart has two atrioventricular (mitral and tricuspid) and two semilunar (aortic and pulmonary) valves.

Q23. Among _ special structure known as substances are water, acids, bases, and salts.

• A. Chemical
• B. Inorganic✓
• C. Physical
• D. Organic

Explanation: Water, acids, bases, and salts are all classified as inorganic compounds. They do not contain the carbon-based structures that define organic compounds.

Q24. Casparian strips are present in:

• A. Endodermis✓
• B. Cotex
• C. Pericycle
• D. Epidermis

Explanation: Correct, because Casparian strips are waxy structures found in the endodermis, controlling water and nutrient flow into the vascular system.

Q25. Which is the function associated with the Golgi apparatus?

• A. Modification of proteins and lipids✓
• B. Protein synthesis
• C. Nerve impulse transmission
• D. Detoxification of drugs

Explanation: Correct, because the Golgi apparatus processes, modifies, and packages proteins and lipids before they are transported.

Q26. Cerebrospinal Fluid (CSF) is found between:

• A. Pia and dura mater
• B. Dura and arachnoid mater
• C. Arachnoid and pia mater✓
• D. Cranium and dura mater

Explanation: CSF is located in the subarachnoid space between these two layers. Acts as a cushion, shock absorber, and waste removal system for the central nervous system.

Q27. The butterfly-shaped central part of the spinal cord is composed of a special structure known as:

• A. Grey Matter✓
• B. White Matter
• C. Both A and B
• D. Neuroglial Protein

Explanation: The central, butterfly-shaped part of the spinal cord is the grey matter, which is primarily composed of neuron cell bodies, dendrites, and unmyelinated axons. This grey matter is surrounded by white matter, which contains myelinated axons that transmit signals up and down the spinal cord.

Q28. Which one is a chemotherapeutic agent to destroy and stop the growth of bacteria?

• A. Phenol
• B. Spirit
• C. Pencilin✓
• D. Sulphuric Acid

Explanation: Correct, as it is an antibiotic that inhibits bacterial cell wall synthesis.

Q29. During muscle contraction, troponin binds to all of the following EXCEPT:

• A. actin
• B. myosin✓
• C. Tropomyosin
• D. Calcium

Explanation: Correct, because troponin does not bind directly to myosin; instead, it interacts with actin and tropomyosin.

Q30. With reference to female reproduction, the exchange of which material is non-placental?

• A. Wastages
• B. Gases
• C. Blood✓
• D. Nutrients

Explanation: Correct, because maternal and fetal blood do not mix; only nutrients and gases diffuse through the placenta.

Q31. The largest group in the animal kingdom is:

• A. Arthropoda✓
• B. Mammals
• C. Mollusca
• D. Nematodes

Explanation: Correct, as this phylum includes insects, crustaceans, and arachnids, making it the largest animal group.

Q32. The different members of colonies in coelenterates that perform different functions are:

• A. Workers
• B. Drones
• C. Zooplanktons
• D. Zooids✓

Explanation: Correct, because coelenterates like corals and siphonophores have specialized individuals called zooids that perform different functions.

Q33. Which of the following is incorrect about lungs?

• A. Occupy intrathoracic cavity
• B. Slightly unequal in size
• C. Respiratory organ of all organisms✓
• D. Encased in pleura

Explanation: Not all organisms have lungs; some use gills, skin, or tracheal systems for respiration.

Q34. Which of the following is responsible for producing the "LUB DUB" sound of the heart?

• A. Closing of valves in heart✓
• B. Contraction of atria
• C. Contraction of muscles
• D. Contraction of ventricles

Explanation: Correct, as the "lub" sound is caused by the closing of atrioventricular valves, and the "dub" sound is due to the closing of semilunar valves.

Q35. What are capsomeres composed of?

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

Explanation: Correct. Capsomeres are protein subunits that assemble to form the viral capsid, which provides structural support and protection for the viral genome.

Q36. After ovulation, the ruptured follicle is transformed into a glandular mass called:

• A. Graafian follicle
• B. Corpus allatum
• C. Primary follicle
• D. Corpus luteum✓

Explanation: Correct. After ovulation, the ruptured follicle forms the corpus luteum, which secretes progesterone to maintain the uterine lining for possible pregnancy.

Q37. Tristearin is a/an:

• A. Lipid✓
• B. Protein
• C. Enzymes
• D. Amino Acid

Explanation: Tristearin is a triglyceride composed of glycerol and three stearic acid molecules, making it a type of lipid.

Q38. What will be the F2 phenotypic ratio if a red-flower male plant is bred with a white-flower female plant, where red flower color is dominant over white flower color?

• A. In ratio of 1:2
• B. In ratio of 1:1
• C. In ratio of 3:1✓
• D. In ratio of 1:3

Explanation: When heterozygous red-flowered F1 plants (Rr) self-pollinate, the F2 generation results in a 3 red : 1 white phenotypic ratio.

Q39. Upon hydrolysis, cellulose yields:

• A. A disaccharide called cellobiose✓
• B. A trisaccharide called cellobiose
• C. A monosaccharide called galactose
• D. A disaccharide called maltose

Explanation: Cellulose breaks down step by step. First, it is hydrolyzed into cellobiose, which is a disaccharide made of two glucose units. Cellobiose is then further hydrolyzed to release individual glucose molecules.

Q40. HIV belongs to which group of viruses?

• A. DNA virus
• B. DNA enveloped virus
• C. Protein tumor virus
• D. Retrovirus✓

Explanation: HIV (Human Immunodeficiency Virus) is an RNA virus that uses reverse transcriptase to convert its RNA into DNA inside host cells.This ability to reverse the normal flow of genetic information (RNA → DNA) classifies it as a retrovirus.

Q41. Which cell type does not have histones with DNA to make chromosomes?

• A. Fungal cell
• B. Plant cell
• C. Animal cell
• D. Bacterial cell✓

Explanation: Bacterial cell – Correct. Bacteria have circular DNA that lacks histones, unlike eukaryotic chromosomes.

Q42. Lactic acid accumulation in skeletal muscle cells causes:

• A. Muscular atrophy
• B. Muscle cramp
• C. Muscle fatigue✓
• D. Muscle tetany

Explanation: Muscle fatigue – Correct. Lactic acid buildup lowers muscle pH, leading to fatigue and reduced contraction efficiency.

Q43. In how many stages is the HIV infection process divided?

• A. 1
• B. 2
• C. 3✓
• D. 4

Explanation: HIV progresses through three main stages: an early phase where the person carries the virus without clear symptoms, a middle phase marked by mild illnesses and immune weakness, and a final phase where the immune system is severely damaged and full-blown AIDS develops.

Q44. What is the color of Chlorophyll-a molecules?

• A. Bluish green✓
• B. Yellowish green
• C. Dark green
• D. Reddish green

Explanation: Bluish green – Correct. Chlorophyll-a absorbs red and blue light, reflecting a bluish-green color.

Q45. The thick filament, which is 16nm in diameter, is composed of?

• A. Actin
• B. Myosin✓
• C. Tropomyosin
• D. Troponin

Explanation: Myosin – Correct. Myosin forms the thick filament in muscle fibers, responsible for contraction by interacting with actin.

Q46. Enzymes lower the activation energy by stabilizing the transition state of a metabolic reaction due to?

• A. Changing conditions within the active site✓
• B. Changing conditions within the protein framework
• C. Rearranging the fatty acids in the active site
• D. Distorting the molecules in the allosteric site

Explanation: Changing conditions within the active site – Correct. Enzymes reduce activation energy by stabilizing the transition state within the active site, facilitating the reaction.

Q47. Which among the following permits interbreeding among individuals of the same species?

• A. Reproductive isolation
• B. Mutation
• C. Chromosomal aberration
• D. Common habitat✓

Explanation: Common habitat – Correct. Living in the same habitat increases chances of mating within a species.

Q48. When do anti-A and anti-B antibodies appear in plasma?

• A. During early development
• B. During the first few months of life✓
• C. At the age of puberty
• D. When exposed to the wrong blood group

Explanation: During the first few months of life – Correct. Anti-A and anti-B antibodies begin to appear in an infant’s blood plasma around 3-6 months after birth due to exposure to environmental antigens.

Q49. Which of the following is NOT an event of light-dependent reactions during photosynthesis?

• A. Photolysis of water
• B. Production of ATP by photophosphorylation
• C. Reduction of Carbon dioxide✓
• D. Reduction of NADP to NADPH

Explanation: Reduction of Carbon dioxide – Correct. Carbon dioxide reduction occurs in the Calvin cycle, which is part of the light-independent reactions, not the light-dependent stage.

Q50. What are the living cells of cartilage called?

• A. Astrocytes
• B. Chondrocytes✓
• C. Osteocytes
• D. Melanocytes

Explanation: Chondrocytes – Correct. These are the specialized cells found in cartilage that produce and maintain the cartilaginous matrix.

Q51. In prokaryotic cells, which one of the following organelles is present?

• A. Mitochondria
• B. Nucleus
• C. Golgi apparatus
• D. Ribosomes✓

Explanation: Ribosomes – Correct. Prokaryotic cells have ribosomes (70S type) for protein synthesis, though they are smaller than eukaryotic ribosomes.

Q52. Phycocyanin is a pigment present in cyanobacteria. Phycocyanin is of _ color.

• A. Green
• B. Blue✓
• C. Yellow
• D. Red

Explanation: Blue – Correct. Phycocyanin is a blue pigment found in cyanobacteria that assists in photosynthesis.

Q53. The flow of lymph is always towards _?

• A. Carotid arteries
• B. Iliac arteries
• C. Thoracic lymph duct✓
• D. Thymus gland

Explanation: Thoracic lymph duct – Correct. Lymph from most of the body drains into the thoracic duct, which empties into the bloodstream.

Q54. Fossil of Cro-Magnon was collected from?

• A. South America
• B. Great Britain
• C. Ireland
• D. France✓

Explanation: France – Correct. The first Cro-Magnon fossils were discovered in France, in the Dordogne region, in 1868.

Q55. NAD is a:

• A. Mononucleotide
• B. Dinucleotide✓
• C. Trinucleotide
• D. Polynucleotide

Explanation: Dinucleotide – Correct. NAD (Nicotinamide Adenine Dinucleotide) is composed of two nucleotides linked together: one with adenine and the other with nicotinamide.

Q56. Which of the following is a viral sexually transmitted disease?

• A. Dengue
• B. Genital Herpes✓
• C. Gonorrhea
• D. Syphilis

Explanation: Genital herpes is an STI that develops when someone becomes infected with the Herpes Simplex Virus, usually HSV-2 and sometimes HSV-1. The virus enters through small breaks in the skin or mucosa during sexual contact and establishes a lifelong infection. Once it’s in the body, it can stay dormant in nerve cells and reactivate from time to time, causing outbreaks of painful sores or sometimes no symptoms at all.

Q57. In prokaryotes, the function of mitochondria is performed by which one of the following?

• A. Mesosome✓
• B. Periplasm
• C. Ribosome
• D. Plasmid

Explanation: Mesosome – Correct. In prokaryotic cells, mesosomes are infoldings of the plasma membrane that perform functions similar to mitochondria, such as cellular respiration.

Q58. Sterilization of blood products is carried out by?

• A. Chemicals
• B. Drying
• C. Heat
• D. Radiation✓

Explanation: Radiation – Correct. Gamma or UV radiation is used to sterilize blood products without damaging them.

Q59. Which hormone controls the release of milk from the mammary glands?

• A. Follicle-stimulating hormone
• B. Progesterone
• C. Luteinizing hormone
• D. Oxytocin✓

Explanation: Oxytocin is a hormone produced by the hypothalamus and released by the pituitary gland that plays a key role in social bonding, childbirth, and lactation. It stimulates uterine contractions during labor and helps with the release of milk after childbirth.

Q60. Which of the following is a conjugated molecule?

• A. Polysaccharides
• B. Glycoproteins✓
• C. Glycogen
• D. Starch

Explanation: Glycoproteins – Correct. Glycoproteins are conjugated molecules containing both protein and carbohydrate components.

Q61. Who discovered the ABO blood group system?

• A. Bernstein
• B. Mendel
• C. Landsteiner✓
• D. Levine

Explanation: Landsteiner – Correct. Karl Landsteiner discovered the ABO blood group system in 1901.

Q62. As water changes into vapor:

• A. Its molecules move at a slower pace
• B. It warms the surrounding environment
• C. Its kinetic energy decreases
• D. It cools the surrounding environment✓

Explanation: It cools the surrounding environment – Correct. Evaporation takes heat from nearby surfaces to provide the energy needed for water molecules to escape, and this loss of heat produces a cooling effect.

Q63. What are nerve impulses?

• A. Electromechanical Waves
• B. Electromagnetic Waves
• C. Electromechno Waves
• D. Electrochemical Waves✓

Explanation: Nerve impulses are electrochemical because they involve both electrical and chemical changes. Electrical changes occur as ions like sodium and potassium move across the nerve cell membrane, creating an electrical signal called an action potential. Chemical changes happen at the synapse, where the electrical impulse triggers the release of neurotransmitters, which are chemical messengers that carry the signal to the next neuron or cell.

Q64. Which one of the following is the direct source of energy in living bodies?

• A. ATP✓
• B. Glucose
• C. Amino acid
• D. Fatty acid

Explanation: The direct source of energy in living bodies is ATP (Adenosine Triphosphate). It stores energy in phosphate bonds, releasing it when broken down to fuel cellular processes.

Q65. Epididymis opens into:

• A. Vas deferens✓
• B. Ejaculatory duct
• C. Urinogenital duct
• D. Vas efferens

Explanation: Vas deferens – Correct. The epididymis stores sperm and then transports it to the vas deferens for ejaculation.

Q66. The phenomenon responsible for genetic variation is:

• A. Mitosis
• B. Cloning
• C. Gene linkage
• D. Crossing over✓

Explanation: Crossing over – Correct. Crossing over during meiosis exchanges genetic material between homologous chromosomes, leading to genetic diversity.

Q67. The infundibulum connects the pituitary gland to the:

• A. Cerebellum
• B. Cerebrum
• C. Hypothalamus✓
• D. Thalamus

Explanation: Hypothalamus – Correct. The infundibulum is a stalk that connects the pituitary gland to the hypothalamus, allowing hormonal regulation.

Q68. Both enzymes and coenzymes are:

• A. Inorganic
• B. Reused✓
• C. Derived from vitamins
• D. Globular proteins

Explanation: Reused – Correct. Enzymes and coenzymes are not consumed in reactions and can be used repeatedly.

Q69. Trans face of the Golgi complex is a:

• A. Forming face that consists of young cisternae
• B. Forming face that consists of old cisternae
• C. Maturing face that consists of newly built cisterna
• D. Maturing face that consists of old cisternae✓

Explanation: Maturing face that consists of old cisternae – Correct. The trans face is the maturing face where modified proteins and lipids are packaged and transported.

Q70. Which type of organisms first evolved about 1.5 billion years ago?

• A. Prokaryotes
• B. Eukaryotes✓
• C. Animals
• D. Seed plants

Explanation: Eukaryotes – Correct. Fossil evidence suggests eukaryotic cells first appeared around 1.5 billion years ago.

Q71. Which of the following statement is NOT true about proteins?

• A. Proteins are nitrogenous compounds
• B. Proteins are building blocks of tissues
• C. Proteins are hydrated carbons✓
• D. Proteins are polymers of amino acids

Explanation: Proteins are hydrated carbons – Incorrect and the correct choice. Proteins are composed of amino acids, not just hydrated carbon structures like carbohydrates.

Q72. Trace amounts of vitamins are the basic natural reservoir in making?

• A. Calcium
• B. Magnesium
• C. Copper
• D. Iron✓

Explanation: Iron – Correct. Some vitamins, such as Vitamin C, help in iron absorption and metabolism. Iron is vital for carrying oxygen from the lungs to the rest of the body through haemoglobin in red blood cells. It is also essential for growth, energy production, DNA synthesis, a healthy immune system, and proper brain function. Without enough iron, the body can become fatigued and weak, and the risk of infection increases.

Q73. Cyanides block the action of enzymes by combining with:

• A. Prosthetic group✓
• B. Coenzyme
• C. Cofactor
• D. Activator

Explanation: Prosthetic group – Correct. Cyanide binds to the iron in cytochrome oxidase, a prosthetic group, inhibiting respiration

Q74. Action potential in the neuronal membrane starts the process of?

• A. Polarization
• B. Depolarization✓
• C. Repolarization
• D. Hyperpolarization

Explanation: When an action potential begins, sodium ions rush in, making the inside of the neuron less negative, which is called depolarization. The influx of positive ions opens ion channels, causing the inside of the cell to become more positive and initiating a cellular response.

Q75. The maximum water potential of pure water is:

• A. -100
• B. 0✓
• C. 1
• D. 100

Explanation: 0 – Correct. Pure water at standard conditions has the highest water potential, which is defined as zero. Any addition of solute lowers the potential, making it negative.

Q76. Fasciola, an endoparasite in sheep, is mostly found in:

• A. Blood of sheep
• B. Large intestine of sheep
• C. Liver and bile duct of sheep✓
• D. Stomach of sheep

Explanation: Liver and bile duct of sheep – Correct. Fasciola hepatica (liver fluke) resides in the liver and bile ducts, causing liver rot.

Q77. In chlorophyll a, a -CH₃ group is attached to which pyrrole ring?

• A. 1st✓
• B. 2nd
• C. 3rd
• D. 4th

Explanation: 1st – Correct. In chlorophyll a, a methyl (-CH₃) group is attached to the first pyrrole ring, distinguishing it from chlorophyll b, which has a formyl (-CHO) group instead.

Q78. Which of the following organelles contains circular DNA and small-sized ribosomes?

• A. Nucleus
• B. Mitochondria✓
• C. Golgi complex
• D. Endoplasmic reticulum

Explanation: Mitochondria – Correct. Mitochondria have their own circular DNA and 70S ribosomes, similar to prokaryotes

Q79. Which of the following transport processes require energy for the movement of material across the plasma membrane?

• A. Osmosis
• B. Diffusion
• C. Endocytosis✓
• D. Facilitated diffusion

Explanation: Endocytosis – Correct. Endocytosis is an active transport mechanism that requires energy to engulf large molecules into the cell.

Q80. The mode of inheritance in humans can be traced through:

• A. Experimental Mating
• B. Chi-Square Chart
• C. Pedigree Analysis✓
• D. Probability Analysis

Explanation: Pedigree Analysis – Correct. Pedigree analysis tracks inheritance patterns through family generations.

Q81. Animals having jointed legs and a chitinous exoskeleton are known as:

• A. Chordates
• B. Arthropods✓
• C. Annelida
• D. Mollusca

Explanation: Arthropods – Correct. Arthropods, such as insects, crustaceans, and arachnids, have jointed appendages and a chitinous exoskeleton.

Q82. Passage of water across a selectively permeable membrane is called:

• A. Active transport
• B. Osmosis✓
• C. Pinocytosis
• D. Facilitated diffusion

Explanation: Osmosis – Correct. Osmosis is the passive movement of water across a selectively permeable membrane from an area of high water potential to low water potential.

Q83. The system in which three angles and axes are unequal is called?

• A. Cubic system
• B. Triclinic system✓
• C. Orthorhombic system
• D. Trigonal system

Explanation: Triclinic system – Correct. The triclinic system has three unequal axes, and none of the angles are 90°, making it the most asymmetrical crystal system

Q84. Which one is incorrect for actual yield being less than theoretical yield?

• A. Mechanical losses
• B. Reversibility of reaction
• C. All molecules do not possess activation energy
• D. Substance is pure✓

Explanation: Substance is pure – correct. The purity of the substance does not affect actual yield since purity mainly influences reactant availability but does not inherently reduce yield.

Q85. Which of the following is the carbon atom of a carbonyl group?

• A. sp hybridized
• B. sp²✓
• C. sp³ hybridized
• D. dsp²

Explanation: sp² hybridized – Correct. In a carbonyl group (C=O), the carbon is sp² hybridized, with one sigma bond and one pi bond.

Q86. The acylium ion has a positive charge and acts as

• A. Nucleophile
• B. Electrophile✓
• C. Carbocation
• D. Carbanion

Explanation: Electrophile – Correct. The acylium ion (RCO⁺) is electron-deficient, making it an electrophile that seeks electrons

Q87. Why is the first ionization energy of Beryllium higher than Boron?

• A. Boron has a higher electronic configuration than Beryllium
• B. Atomic radius of Beryllium is smaller than Boron
• C. Beryllium has a stable electronic configuration✓
• D. Boron has a smaller atomic number than Beryllium

Explanation: Beryllium has a stable electronic configuration – Correct. Beryllium has a fully filled 2s orbital, which is more stable and requires more energy to remove an electron compared to Boron, where the electron is in a higher-energy 2p orbital.

Q88. Which one of the following has no cleavage plane?

• A. Graphite
• B. NaCl crystals
• C. Copper crystals✓
• D. Ice

Explanation: Copper crystals – Correct. Copper is a metallic crystal with a face-centered cubic structure that lacks cleavage planes but can deform plastically.

Q89. Which of the following metals does not react with water?

• A. Mg
• B. Ca
• C. Na
• D. Be✓

Explanation: Be – Correct. Beryllium does not react with water under normal conditions due to the formation of an oxide layer that prevents further reaction.

Q90. A set of postulates that explain the behavior of an ideal gas is called:

• A. Bohr theory
• B. Kinetic molecular theory of gases✓
• C. Rutherford theory
• D. Dalton's theory

Explanation: Kinetic molecular theory of gases – Correct. This theory explains gas behavior using molecular motion, collisions, and kinetic energy principles.

Q91. The general electronic configuration of halide ions is:

• A. ns²np⁵
• B. ns²np⁶✓
• C. ns¹np⁵
• D. ns²np³

Explanation: ns²np⁶ – Correct. Halide ions gain one electron to achieve a full octet, resulting in this configuration.

Q92. Thermodynamically, the most stable form of carbon is:

• A. Diamond
• B. Graphite✓
• C. Peat
• D. Coa

Explanation: Graphite – Correct. Graphite is the most stable allotrope of carbon due to its lower Gibbs free energy.

Q93. Protein content of human milk is about

• A. 1.4%✓
• B. 2.4%
• C. 3.4%
• D. 4.4%

Explanation: 1.4% – Correct. Human milk has a relatively low protein content to support infant digestion.

Q94. By base-catalyzed reaction

• A. Amphoteric
• B. Nucleophilic✓
• C. Electrophobic
• D. Electrophilic

Explanation: Nucleophilic – Correct. Base-catalyzed reactions often involve nucleophiles, which donate electron pairs to electrophiles.

Q95. Which of the following is a bidentate ligand?

• A. Ammine
• B. Hydrazine✓
• C. Aqua
• D. Carbonyl

Explanation: Hydrazine – Correct. Hydrazine (N₂H₄) has two nitrogen atoms, each capable of donating a lone pair, making it a bidentate ligand.

Q96. What do we mean by the term "delocalized electrons" in benzene?

• A. Electrons that are free to move around the molecule in the π bonding system above and below the plane of the carbon atoms in the benzene ring✓
• B. Electrons that are not free to move around the molecule in the π bonding system above and below the plane of the carbon atoms in the benzene ring
• C. Electrons that are free to move around the molecule in the σ bonding system above and below the plane of the carbon atoms in the benzene ring
• D. Electrons that are free to move around the molecule in the π bonding in the benzene ring

Explanation: Electrons that are free to move around the molecule in the π bonding system above and below the plane of the carbon atoms in the benzene ring – Correct. In benzene, the π electrons are delocalized over the ring, contributing to resonance stability.

Q97. Which of the following pairs is isostructural?

• A. AlCl₃ and CH₄
• B. BF₃ and NH₃
• C. SnCl₂ and BeCl₂
• D. SO₃ and BF₃✓

Explanation: SO₃ and BF₃ – Correct. Both have a trigonal planar structure due to sp² hybridization.

Q98. Acetic acid is a weaker acid than sulfuric acid because of which of the following reasons?

• A. It decomposes on increasing temperature
• B. It has a lesser degree of ionization✓
• C. It has a -COOH group
• D. It has more inductive effect

Explanation: It has a lesser degree of ionization – Correct. Acetic acid (CH₃COOH) is weak because it only partially ionizes in water, unlike sulfuric acid (H₂SO₄), which ionizes completely.

Q99. Number of primary carbon atoms present in isobutane

• A. One
• B. Two
• C. Three✓
• D. Four – Incorrect. Isobutane does not have four primary carbon atoms.

Explanation: Three – Correct. Isobutane (C₄H₁₀) has three primary carbon atoms, each bonded to only one other carbon.

Q100. In which method can the rate of reaction involving ions be studied

• A. Electrical conductivity method✓
• B. Optical rotation method
• C. Refractometric method
• D. Spectrometry

Explanation: Electrical conductivity method – Correct. Since ions conduct electricity, changes in conductivity can help monitor the reaction rate

Q101. What occurs when carbonyl compounds react with HCN

• A. The reaction is catalyzed by concentrated H₂SO₄
• B. Pentan-2-one and HCN react to give a chiral product✓
• C. The reaction is a condensation reaction
• D. The reaction is nucleophilic substitution

Explanation: Pentan-2-one and HCN react to give a chiral product – Correct. The addition of HCN to an asymmetric ketone produces a chiral cyanohydrin.

Q102. The overall charge on the transition state in an SN2 reaction is?

• A. Negative
• B. Positive
• C. Neutral
• D. Partially negative✓

Explanation: In an SN2 reaction, the transition state has an overall partial negative charge because both the nucleophile and the leaving group (both electron-rich) are partially attached to the carbon at the same time.

Q103. Which ionic radius is the smallest?

• A. Na⁺
• B. Mg²⁺
• C. Al³⁺✓
• D. Mg⁺

Explanation: Al³⁺ – Correct. Due to its higher charge (+3), Al³⁺ has the strongest attraction to electrons, making its ionic radius the smallest.

Q104. What is the quantum number for the unpaired electron of a chlorine atom (n, l, m)?

• A. (2,1,0)
• B. (2,1,1)
• C. (3,1,1)✓
• D. (3,0,0)

Explanation: (3,1,1) – Correct. The unpaired electron in chlorine is in the 3p orbital, where n=3, l=1, and m=1.

Q105. Group IB is called the coinage metals. Which one is not true about this group?

• A. Have powerful reducing agents✓
• B. Have positive reduction potential
• C. Cannot displace H₂ from dilute acids
• D. Lies below SHE in electrochemical series

Explanation: Have powerful reducing agents – Incorrect. Coinage metals (Cu, Ag, Au) are not strong reducing agents; they have low reactivity and tend to resist oxidation

Q106. What is the weight of oxygen that required for the complete combustion of 3.2 kg of methane?

• A. 3.2 kg
• B. 6.4 kg
• C. 12.8 kg✓
• D. 15.4 kg

Explanation: 12.8 kg: This is the correct answer. Understanding the Chemical Reaction The complete combustion of methane (CH₄) with oxygen (O₂) produces carbon dioxide (CO₂) and water (H₂O). The balanced chemical equation is: CH₄ + 2O₂ → CO₂ + 2H₂O This equation tells us that 1 mole of methane reacts with 2 moles of oxygen. CalculationsMolar Mass:Methane (CH₄): (12.01 g/mol) + 4(1.008 g/mol) ≈ 16.04 g/mol Oxygen (O₂): 2(16.00 g/mol) = 32.00 g/molMoles of Methane:Convert the mass of methane to grams: 3.2 kg * 1000 g/kg = 3200 gCalculate the moles of methane: 3200 g / 16.04 g/mol ≈ 199.5 molesMoles of Oxygen:From the balanced equation, 2 moles of oxygen are required for every 1 mole of methane.Moles of oxygen: 199.5 moles * 2 = 399 molesMass of Oxygen:Calculate the mass of oxygen: 399 moles * 32.00 g/mol = 12768 gConvert grams to Kilograms: 12768g / 1000g/kg = 12.768 kg.

Q107. How many moles of a gas occupy 30.57 L at 55∘C and 0.83 atm?

• A. 0.1 mol
• B. 0.62 mol
• C. 0.84 mol
• D. 0.94 mol✓

Explanation: 0.94 mol: This is the correct answer.Understanding the Ideal Gas Law The ideal gas law is expressed as: PV = nRT Where:P = Pressure (in atm) V = Volume (in liters, L) n = Number of moles R = Ideal gas constant (0.08206 L⋅atm/mol⋅K) T = Temperature (in Kelvin, K) CalculationsConvert Temperature to Kelvin:T = 55°C + 273.15 = 328.15 KPlug in the Given Values:P = 0.83 atmV = 30.57 LR = 0.08206 L⋅atm/mol⋅KT = 328.15 KSolve for n (Number of Moles):n = PV / RT n = (0.83 atm * 30.57 L) / (0.08206 L⋅atm/mol⋅K * 328.15 K)n ≈ 25.3731 / 26.927199n ≈ 0.9423 moles

Q108. Which statement about a 4d orbital is correct?

• A. It is at a higher energy level than a 4p orbital but has the same shape
• B. It is occupied by one electron in an isolated Zn atom
• C. It can hold a maximum of 10 electrons✓
• D. It has the highest energy of the orbitals with principal quantum number 4

Explanation: It can hold a maximum of 10 electrons – Correct. A d-orbital can hold up to 10 electrons (5 orbitals, each accommodating 2 electrons).

Q109. Hess's law states the same thing as

• A. Henry's law
• B. Second law of thermodynamics
• C. First law of thermodynamics✓
• D. Second law of thermochemistry

Explanation: First law of thermodynamics – Correct. Hess’s law is based on the conservation of energy, which aligns with the first law.

Q110. Which of the following is not true about canal rays?

• A. 1.6726 × 10⁻²⁷ kg
• B. 9.54 × 10⁷ C/kg
• C. Show deflection under electric & magnetic fields
• D. Do not cause mechanical motion✓

Explanation: Do not cause mechanical motion – Correct. Canal rays do cause mechanical motion, so this statement is false.

Q111. The solubility of carboxylic acid in water gradually decreases with:

• A. Decreases in molecular mass
• B. Increases in molecular mass✓
• C. Increases the amount of acid
• D. Decreases the amount of water

Explanation: Increases in molecular mass – Correct. Higher molecular mass acids have larger nonpolar hydrocarbon chains, reducing solubility.

Q112. The polar part of soap and detergent dissolves in water molecules due to:

• A. Dipole-dipole forces
• B. Dipole-induced dipole forces
• C. Hydrogen bonding✓
• D. London dispersion forces

Explanation: Hydrogen bonding – Correct. The polar head (–COO⁻ or –SO₃⁻) of soap interacts with water via hydrogen bonding.

Q113. When equal moles of reactants A and B are allowed to react according to the following balanced equation. (2 A+B→Product). The limiting reactant in this chemical equation will be?

• A. Reactant A✓
• B. Reactant B
• C. Reactant A and B
• D. No Limiting reactant:

Explanation: Reactant A: This is the correct answer. Because the balanced equation shows that twice as much A is needed compared to B, having equal moles means A will be used up first.

Q114. The hydrocarbon which has three linear fused benzene rings?

• A. Phenanthrene
• B. Triphenylmethane
• C. Diphenyl ether
• D. Anthracene✓

Explanation: Anthracene consists of three linearly fused benzene rings, making it a polycyclic aromatic hydrocarbon. This structure allows for unique chemical properties and reactivity compared to other hydrocarbons. In contrast, Phenanthrene also has three fused rings, but they are arranged in a non-linear configuration, disqualifying it from being the correct answer. Triphenylmethane features three benzene rings attached to a central carbon, but these rings are not fused, thus they do not meet the criteria of the question. Lastly, Diphenyl ether has two distinct benzene rings linked by an oxygen atom, which keeps them isolated rather than fused.

Q115. Which functional group is characteristic of an ester?

• A. R-CO-R
• B. R-CO-OR✓
• C. R-CO-OH
• D. R-COO-R

Explanation: R-CO-OR is the functional group of an ester, which consists of a carbonyl group bonded to an oxygen attached to another alkyl or aryl group.

Q116. Which of the following acids has the smallest dissociation constant?

• A. CH₃CHFCOOH
• B. FCH₂CH₂COOH
• C. BrCH₂CH₂COOH✓
• D. CH₃CHBrCOOH

Explanation: Br is less electronegative than F. BrCH₂CH₂COOH has the smallest dissociation constant (Ka) → i.e., it is the weakest acid.In CH₃CHBrCOOH the Br is on the α-carbon (the carbon directly next to the COOH). An electronegative substituent directly adjacent to the carboxyl group stabilizes the carboxylate anion strongly by the inductive (–I) effect, so the acid is stronger (larger KaK_aKa​).

Q117. At room temperature, Glycerin boils at 290°C. What is the boiling point of glycerin under vacuum distillation at 50 torr?

• A. 320°C
• B. 310°C
• C. 300°C
• D. 210°C✓

Explanation: 210°C is correct because under reduced pressure, glycerin's boiling point drops significantly.

Q118. The solubility of KClO₃ is decreased by adding

• A. KCl✓
• B. KClO₃
• C. H₂O
• D. Not affected

Explanation: Adding KCl introduces common ions (K⁺ and ClO₃⁻), reducing solubility due to the common ion effect

Q119. For every reaction occurring in the human body, there is at least one type of:

• A. Vitamins
• B. Enzymes✓
• C. Proteins
• D. Amino acids

Explanation: Enzymes catalyze biochemical reactions, making them essential for every reaction in the body.

Q120. Why do transition elements form alloys so easily?

• A. Atomic size✓
• B. Orbital configuration
• C. Very light
• D. Hard elements

Explanation: Transition metals have similar atomic sizes, allowing atoms of different metals to mix and form alloys.

Q121. Methanol is prepared from carbon monoxide and hydrogen. The catalyst used for this reaction is:

• A. ZnO + CoO₂
• B. ZnO + CuO✓
• C. ZnO + Ag₂O
• D. Cn₂O₃ + ZnO

Explanation: ZnO + CuO is the correct catalyst for industrial methanol production from CO and H₂.

Q122. Which of the following statements is true about Grignard reagent (RMgX)?

• A. RMgX is prepared in an aqueous medium
• B. RMgX is prepared in ether✓
• C. RMgX does not react with water
• D. RMgX is inactive in ethanol

Explanation: Grignard reagents are prepared in dry ether to prevent decomposition

Q123. Air at sea level is dense. This is a practical application of:

• A. Boyle’s law✓
• B. Charles’ law
• C. Avogadro’s law
• D. Dalton’s law

Explanation: Boyle’s law states that pressure and volume are inversely related. At sea level, higher pressure compresses air, making it denser.

Q124. Which of the following acids can show cis-trans isomerism?

• A. Malonic acid
• B. Maleic acid✓
• C. Succinic acid
• D. Lactic acid

Explanation: Maleic acid has a C=C double bond with carboxyl groups attached, allowing for cis-trans isomerism.

Q125. What is the reactivity state of Phenols?

• A. Less reactive
• B. More reactive✓
• C. Neutral
• D. Non reactive

Explanation: Phenols undergo electrophilic substitution easily because the lone pair on oxygen increases electron density on the benzene ring.

Q126. Why do electrons have opposite spins when they are in the same orbital?

• A. This condition reduces friction
• B. This condition creates more energy
• C. This condition results in zero magnetism and removes the charge of the electron
• D. This condition results in less repulsion and opposite magnetic fields✓

Explanation: Opposite spins reduce repulsion and result in a stable orbital configuration due to opposing magnetic fields.

Q127. Which of the following is not an endothermic reaction?

• A. Combustion of methane✓
• B. Decomposition of water
• C. Dehydrogenation of ethane or ethylene
• D. Conversion of graphite

Explanation: Combustion of methane releases energy, making it an exothermic reaction.

Q128. Which order of reaction obeys the expression t1/2=1/ka​?

• A. Zero
• B. First
• C. Second✓
• D. Third

Explanation: Second: Correct. The second-order half-life matches the given expression.

Q129. What is the common name of 1,2,3-propanetriol?

• A. Butyl alcohol
• B. Glycol
• C. Glycerol✓
• D. Propyl

Explanation: Glycerol is the common name for 1,2,3-propanetriol.

Q130. When an aqueous solution of NaCl is electrolyzed:

• A. Cl₂ is evolved at the cathode
• B. H₂ is evolved at the cathode✓
• C. Na is deposited at the cathode
• D. Na appears at the anode

Explanation: H₂ is produced at the cathode due to the reduction of H₂O instead of Na⁺.

Q131. The equilibrium stage that is not affected by temperature is called:

• A. Static equilibrium✓
• B. Natural equilibrium
• C. Dynamic equilibrium
• D. Unstable equilibrium

Explanation: Static equilibrium does not involve ongoing reactions and is not influenced by temperature.

Q132. Which of the following carbon atoms is sp² hybridized?

• A. Cyclopropane
• B. Diamond
• C. Graphite✓
• D. Hexane

Explanation: Graphite has sp²-hybridized carbon atoms, forming planar hexagonal layers.

Q133. Sp² hybrid carbon atom is present in

• A. Methanal✓
• B. Methanol
• C. Ethanol
• D. 2-Propanol

Explanation: Methanal (formaldehyde) has a C=O bond, meaning the carbon is sp² hybridized.

Q134. What is the fact due to which branching decreases boiling point?

• A. As branching increases, the attractive forces between molecules increase
• B. As branching increases, it decreases attractive forces
• C. As branching increases, it increases surface area for making attractive forces
• D. As branching increases, it decreases the surface area for attractive forces✓

Explanation: Decreased surface area reduces attractive forces, leading to a lower boiling point.

Q135. Temperature increase in an exothermic reversible reaction shifts the equilibrium to

• A. Product side
• B. Reactant side✓
• C. Remains unchanged
• D. Increase in both

Explanation: According to Le Chatelier's principle, increasing temperature favors the endothermic direction, which is the reactant side.

Q136. Which product is formed when RMgX reacts with CO₂?

• A. Aldehydes
• B. Ketones
• C. Carboxylic acid✓
• D. Ethers

Explanation: RMgX reacts with CO₂ to form an intermediate that, upon hydrolysis, gives a carboxylic acid

Q137. The minimum gradient of a curve on a displacement-time graph of a ball thrown vertically upwards and caught back can be:

• A. Zero✓
• B. 9.81
• C. 90 degrees
• D. Equal to the final velocity of the motion

Explanation: The minimum gradient (slope) is zero at the highest point where velocity is momentarily zero.

Q138. Coulomb's law is only true for point charges whose sizes are:

• A. Medium
• B. Very large
• C. Very small✓
• D. Large

Explanation: Coulomb's law assumes point charges with negligible size for accurate force calculations

Q139. The magnetic field depends upon:

• A. Strength, mass, and nature of magnetic materials
• B. Strength, mass, and direction
• C. Strength, distance, and direction✓
• D. Strength, nature of magnetic materials, and distance

Explanation: The strength of the field, distance from the source, and direction determine magnetic field behavior.

Q140. When a gas is compressed isothermally, the product of its pressure and volume during the process is:

• A. Not constant
• B. Constant✓
• C. Proportional to temperature
• D. Proportional to entropy

Explanation: PV=constant holds for an ideal gas during isothermal compression

Q141. Which one of the following bulbs has the least resistance, if the current is kept constant?

• A. 100 watt
• B. 200 watt
• C. 300 watt
• D. 400 watt✓

Explanation: In this question, we are asked to determine which bulb has the least resistance when the current is kept constant. According to Ohm's law, the resistance (R) of a device is inversely proportional to its power (P) when the current (I) is constant, represented by the formula R = V/I, where V = P/I. Therefore, a bulb with higher wattage consumes more power for the same current, resulting in lower resistance. Thus, the 400 watt bulb has the least resistance, while the 100, 200, and 300 watt bulbs have higher resistances respectively.

Q142. A coil of area 1 m² has 100 turns. It rotates with constant angular velocity about an axis along its diameter perpendicular to Earth's magnetic field of B=1×10−5T. The angular velocity for induced emf of 1 mV is?

• A. Zero
• B. 1 rad/s✓
• C. 7.96 rad/s
• D. 10 rad/s

Explanation: To calculate the induced emf (ε) in the coil as it rotates in a magnetic field, we use the formula: ε = -N * A * B * ω * sin(θ), where N is the number of turns, A is the area of the coil, B is the magnetic field strength, ω is the angular velocity, and θ is the angle between the magnetic field and the normal to the plane of the coil. Given that the coil rotates about an axis perpendicular to the magnetic field, θ = 90 degrees (sin(90°) = 1). Substituting the values: ε = -100 * 1 m² * 1×10⁻⁵ T * ω. For ε = 1 mV (or 1×10⁻³ V), we can solve for ω: 1×10⁻³ = 100 * 1×10⁻⁵ * ω, leading to ω = 1 rad/s. Therefore, option B is correct. Options A, C, and D provide incorrect angular velocities that do not yield the desired induced emf.

Q143. When a transverse wave passes, the particles of the medium oscillate:

• A. With different harmonics
• B. With different frequencies
• C. Parallel to the direction of wave travel
• D. Perpendicular to the direction of wave travel✓

Explanation: In transverse waves, particles oscillate perpendicular to wave motion

Q144. A capacitor is charged with a battery, storing energy U. An identical capacitor is connected in parallel to the first one. The energy stored in each capacitor is:

• A. U
• B. U/2✓
• C. 4U
• D. 2U

Explanation: Energy in a parallel circuit is divided equally among identical capacitors.

Q145. If the value of acceleration due to gravity 'g' is reduced to half, the time of flight T of projectile becomes:

• A. T/2
• B. T/4
• C. 2T✓
• D. 4T

Explanation: 2T Explanation: The time of flight (T) of a projectile is given by the formula: T = 2v₀sin(θ) / g, where v₀ is the initial velocity, θ is the launch angle, and g is the acceleration due to gravity. If 'g' is reduced to 'g/2', we can substitute this into the formula: T' = 2v₀sin(θ) / (g/2). This simplifies to T' = 4v₀sin(θ) / g, which can be rewritten as T' = 2 * (2v₀sin(θ) / g) = 2T. Therefore, the time of flight doubles.

Q146. Which of the following has the largest energy?

• A. A photon of wavelength 1nm
• B. A photon of wavelength 50 μm
• C. A photon of wavelength 2 pm✓
• D. A photon of wavelength 200 nm

Explanation: A photon of wavelength 2 pmExplanation:The energy (E) of a photon is related to its wavelength (λ) by the equation: E = hc / λ, where h is Planck's constant and c is the speed of light.This equation shows that energy is inversely proportional to wavelength. Therefore, the shorter the wavelength, the higher the energy.We need to compare the wavelengths:1 nm = 1 × 10⁻⁹ m50 μm = 50 × 10⁻⁶ m2 pm = 2 × 10⁻¹² m200 nm = 200 × 10⁻⁹ m2 pm is the shortest wavelength, so it corresponds to the highest energy.

Q147. How much energy is converted in a resistor of 5 ohm carrying a current of 2.0 A after 10 seconds?

• A. 4.0 J
• B. 25 J
• C. 100 J
• D. 200 J✓

Explanation: Explanation:The energy (E) dissipated in a resistor is given by the formula: E = I²Rt, where I is the current, R is the resistance, and t is the time.Substituting the given values: E = (2.0 A)² * (5 Ω) * (10 s) = 4 * 5 * 10 = 200 J.

Q148. The longest wavelength of Lyman series is equal to?

• A. 1/RH
• B. 9/RH
• C. 4/3 RH✓
• D. 4/2RH

Explanation: Explanation:The Lyman series corresponds to transitions to the n = 1 energy level in the hydrogen atom.The longest wavelength corresponds to the transition from n = 2 to n = 1, which has the smallest energy difference.Using the Rydberg formula: 1/λ = RH (1/n₁² - 1/n₂²), where n₁ = 1 and n₂ = 2.1/λ = RH (1/1² - 1/2²) = RH (1 - 1/4) = RH (3/4).Therefore λ = 4/(3RH)

Q149. What is the SI unit of conductivity?

• A. Ohm−1m
• B. mho m−1✓
• C. siemen m
• D. mho−1m−2

Explanation: Explanation:Conductivity (σ) is the reciprocal of resistivity (ρ). Resistivity has units of ohm-meter (Ω⋅m).Therefore, conductivity has units of 1/(Ω⋅m) or ohm⁻¹m⁻¹.Ohm⁻¹ is also called mho or Siemens. Therefore mho/m or siemens/m are valid units.

Q150. The angle subtended at the center of a circle by an arc equal to 1/60th of a degree is called:

• A. One minute✓
• B. One radian
• C. One second
• D. One steradian

Explanation: One minute Explanation: A degree is divided into 60 equal parts called minutes. Therefore, 1/60th of a degree is defined as one minute.

Q151. The magnetic flux through an area A in a uniform magnetic field B is given as:

• A. B.A✓
• B. BA sinθ
• C. BA Cos 2θ
• D. BA tanθ

Explanation: Explanation: Magnetic flux (Φ) is defined as the dot product of the magnetic field vector (B) and the area vector (A): Φ = B⋅A. This can also be expressed as Φ = BAcos(θ), where θ is the angle between the magnetic field and the normal to the area. B.A is the most concise way to represent this.

Q152. High-frequency vibration is of:

• A. 10 kHz
• B. 0.1 MHz✓
• C. 1 kHz
• D. 1000Hz

Explanation: Explanation:Frequency is measured in Hertz (Hz). Higher frequency means more cycles per second.1 kHz = 1000 Hz, 1 MHz = 1,000,000 Hz.0.1 MHz = 100,000 Hz, which is the highest frequency among the given options.10 kHz is 10,000 Hz. 1000Hz is 1 kHz.

Q153. Electric field lines are:

• A. Actual lines
• B. Imaginary lines✓
• C. Solid lines
• D. Always curve lines

Explanation: Imaginary lines Explanation: Electric field lines are a conceptual tool used to visualize the electric field. They represent the direction and relative strength of the electric field. They are not physical lines that exist in reality.

Q154. In British Engineering system, 1 Horse Power

• A. 550 ft Pound/sec✓
• B. 746 ft Pound/sec
• C. 550 watt
• D. 550 kilowatt hour

Explanation: Explanation: In the British Engineering system, 1 horsepower (hp) is defined as the power required to lift 550 pounds by 1 foot in 1 second. Therefore, 1 hp = 550 ft-lb/s.

Q155. Two point charges, each of magnitude q, are separated by a distance 2d. At a point mid-way between:

• A. E=0,V=0
• B. E≠0,V=0
• C. E=0,V≠0✓
• D. E≠0,V≠0

Explanation: E=0,V≠0 Correct. The electric field at the midpoint cancels out because the two charges create fields in opposite directions. However, the potential is the sum of contributions from both charges, which is nonzero.

Q156. A low energy neutron has RBE factor of 10. How much energy is absorbed by a man of mass 80 Kg. if the value of equivalent dose is 400 rem?

• A. 16 J
• B. 32 J✓
• C. 48 J
• D. 64 J

Explanation: Explanation:Equivalent dose (rem) = RBE factor × Absorbed dose (rad) Absorbed dose (rad) = Equivalent dose (rem) / RBE factor = 400 rem / 10 = 40 rad.1 rad = 0.01 J/kg.Total absorbed energy (J) = Absorbed dose (rad) × Mass (kg) × 0.01 J/kg/rad = 40 rad × 80 kg × 0.01 J/kg/rad = 32 J.

Q157. A circuit that converts pulsating voltage of the rectifier to smooth voltage is known as:

• A. Generator
• B. Transformer
• C. Filter✓
• D. Choke

Explanation: Explanation: A filter circuit is specifically designed to smooth out the pulsating DC voltage produced by a rectifier. It typically uses capacitors and inductors to remove the AC ripple.

Q158. An object of mass 'm' moving with speed 'v' has a head-on wave collision with another object of mass 4m′ moving with speed v′ in the opposite direction. The objects stick together after the collision. What is the total loss of the kinetic energy

• A. (1/2)mv²
• B. 2mv'²
• C. (1/10)mv
• D. (18/5)mv'²✓

Explanation: Initial Kinetic Energy (KE_initial):KE of mass m: (1/2)mv²KE of mass 4m: (1/2)(4m)v'² = 2mv'²Total KE_initial: (1/2)mv² + 2mv'²Substitute v = 2v':Total KE_initial: (1/2)m(2v')² + 2mv'² = 2mv'² + 2mv'² = 4mv'²Final Velocity (V_final) using Conservation of Momentum:Initial momentum: mv - 4mv'Substitute v = 2v': m(2v') - 4mv' = -2mv'Final momentum: (m + 4m)V_final = 5mV_finalConservation: -2mv' = 5mV_finalV_final = -2v'/5Final Kinetic Energy (KE_final):KE_final: (1/2)(5m)V_final² = (1/2)(5m)(-2v'/5)² = (1/2)(5m)(4v'²/25) = (2/5)mv'²Loss of Kinetic Energy (ΔKE):ΔKE = KE_initial - KE_final = 4mv'² - (2/5)mv'² = (20/5)mv'² - (2/5)mv'² = (18/5)mv'²

Q159. If Cv denotes molar specific heat at constant volume and △T is the change in temperature, then CvΔT gives:

• A. Volume
• B. Pressure
• C. Entropy
• D. Internal energy✓

Explanation: Internal energy Explanation: The change in internal energy (ΔU) of an ideal gas at constant volume is given by ΔU = nCvΔT, where n is the number of moles. If n=1 then ΔU=CvΔT.

Q160. If the initial velocity ′u′ of the projectile is doubled, height H' of the projectile becomes:

• A. H/2
• B. H/4
• C. 2H
• D. 4H✓

Explanation: 4H Explanation: The maximum height (H) of a projectile is given by H = u²sin²(θ) / 2g, where u is the initial velocity, θ is the launch angle, and g is the acceleration due to gravity. If u is doubled (2u), the new height (H') will be H' = (2u)²sin²(θ) / 2g = 4u²sin²(θ) / 2g = 4H.

Q161. A step down transformer is used to light a 12 volt 24 mA lamp from the 240 mains the current through primary is 1.5 mA. What is the efficiency of the transformer?

• A. 60%
• B. 70%
• C. 90%
• D. 80%✓

Explanation: Explanation:Efficiency (η) = (Output power / Input power) × 100% Output power (Ps) = VsIs = 12 V × 24 mA = 288 mWInput power (Pp) = VpIp = 240 V × 1.5 mA = 360 mWη = (288 mW / 360 mW) × 100% = 80%

Q162. An oscillator performing simple harmonic motion has a displacement given by the x=8.0(mm)sin(10π/3)t. What is the displacement when t=0.05s?

• A. 4√2 mm
• B. 4√3 mm
• C. 8 mm
• D. 4 mm✓

Explanation: Explanation: x = 8.0 sin(10π/3 × 0.05) = 8.0 sin(π/6) = 8.0 × 0.5 = 4.0 mm

Q163. According to the wave-particle duality, identify respectively how all micro-particles (electrons, protons, atoms, etc) behave when propagating and when exchanging energies

• A. Waves, particles✓
• B. Particles, waves
• C. Particles, particles
• D. Waves, waves:

Explanation: Explanation: Wave-particle duality states that micro-particles exhibit both wave-like and particle-like properties. When propagating (moving through space), they behave as waves (e.g., diffraction, interference). When exchanging energies (e.g., in interactions, emissions, absorptions), they behave as particles (e.g., photoelectric effect).

Q164. A solenoid of length 10 cm has magnetic flux density B=0.50T. When there is free space inside its turns. When the same solenoid is wounded on iron core then its flux density is increased by

• A. 14 times
• B. 7 times
• C. Remains Same
• D. 140 times✓

Explanation: 140 times Explanation: Iron is a ferromagnetic material, which significantly increases magnetic flux density when placed in a magnetic field. The increase is due to the high permeability of iron. typical relative permeability of iron is in the hundreds. therefore an increase of 140 times is a realistic value.

Q165. Angular displacement is a vector quantity only when the?

• A. Time of a circular motion is large enough
• B. Time of circular motion has no effect
• C. Time of circular motion is moderate
• D. Time of circular motion is small enough✓

Explanation: Time of circular motion is small enoughExplanation: Angular displacement is a vector when the rotation is small enough to treat it as a vector. This is because small rotations commute (order doesn't matter). Large rotations do not commute. When the time is small, the angular displacement is small.

Q166. Volt can also be written as?

• A. JC−2
• B. JC
• C. CN−1
• D. JC−1✓

Explanation: JC−1Explanation: Volt (V) is defined as the potential difference, which is work (energy) per unit charge. Therefore, V = J/C (Joules per Coulomb) or JC⁻¹.

Q167. A low voltage supply with an e.m.f. of 20 V and an internal resistance of 1.5 ohms is used to supply power to a heater of resistance 6.5 ohms in a fish tank. What is the power supplied to the water in the fish tank?

• A. 50 W
• B. 41 W✓
• C. 53 W
• D. 62 W

Explanation: Explanation:Total resistance (R) = internal resistance (r) + heater resistance (R_heater) = 1.5 Ω + 6.5 Ω = 8 Ω. Current (I) = emf (ε) / R = 20 V / 8 Ω = 2.5 A. Power (P) = I²R_heater = (2.5 A)² × 6.5 Ω = 40.625 W ≈ 41 W.

Q168. When a nucleus emits beta particle, its mass number remains constant but charge number increases by:

• A. 2
• B. 3
• C. 4
• D. 1✓

Explanation: Explanation: Beta decay involves the transformation of a neutron into a proton (or vice versa). This increases the atomic number (charge number) by 1, while the mass number remains the same.

Q169. The direction of centripetal acceleration in a circle?

• A. Opposite to the centripetal force
• B. Tangent to the circle
• C. Parallel to the circle
• D. Parallel to the centripetal force✓

Explanation: Parallel to the centripetal forceExplanation: Centripetal acceleration and centripetal force always point towards the center of the circle. Therefore, they are parallel to each other.

Q170. The time constant of an RC circuit during discharge is that time in which charge on plates, as compared to maximum charge

• A. 25 percent
• B. 50 percent
• C. 63.3 percent
• D. 36.8 percent✓

Explanation: Explanation:During the discharge of an RC circuit, the charge on the capacitor decreases exponentially according to the formula: Q(t) = Q₀e^(-t/RC), where Q(t) is the charge at time t, Q₀ is the initial charge, and RC is the time constant.When t = RC (one time constant), Q(RC) = Q₀e^(-1) ≈ 0.368Q₀.This means the charge remaining is approximately 36.8% of the initial charge.

Q171. Doppler effect can be observed by:

• A. Longitudinal waves
• B. Electromagnetic waves
• C. Sound only
• D. Both longitudinal and electromagnetic waves✓

Explanation: Explanation: The Doppler effect occurs whenever there is relative motion between a source of waves and an observer. It applies to both longitudinal waves (like sound) and electromagnetic waves (like light).

Q172. The induced emf in a coil is 1 V. What will be the rate of change of area of that coil placed in a constant magnetic field of strength 0.1T ?

• A. 0.1 m²s⁻²
• B. 0.01 m²s⁻²
• C. 1 m²s⁻²
• D. 10 m²s⁻¹✓

Explanation: Explanation:Induced emf (ε) = B(dA/dt), where B is the magnetic field and dA/dt is the rate of change of area. 1 V = (0.1 T)(dA/dt). dA/dt = 1 V / 0.1 T = 10 m²/s.

Q173. Work done on a rod moving in a magnetic field across magnetic field and generate an emf in the system. This statement is according to lenzs law of conservation of?

• A. Mass
• B. Momentum
• C. Density
• D. Energy✓

Explanation: Explanation:Lenz's law is a consequence of the law of conservation of energy. The induced emf opposes the change that produced it, ensuring that energy is conserved.

Q174. De Broglie received the Nobel Prize in the year:

• A. 1905
• B. 1927
• C. 1929✓
• D. 1937

Explanation: Explanation: Louis de Broglie received the Nobel Prize in Physics in 1929 for his discovery of the wave nature of electrons.

Q175. Time of flight of a projectile depends upon

• A. Launch angle only
• B. Launch speed only
• C. Launch speed and its angle✓
• D. Launch height only

Explanation: Launch speed and its angleCorrect. The time of flight (T) is given by the equation:T=2v0sin⁡θ/gThis equation shows that both the initial speed (v0​) and the launch angle (θ\thetaθ) determine the time of flight.

Q176. Which of the following is NOT CORRECT about potentiometer?

• A. It measures the emf of a cell very accurately
• B. Its sensitivity is low✓
• C. It is based on the null deflection method
• D. Its sensitivity is high

Explanation: Incorrect. This statement is not correct because potentiometers are highly sensitive due to their null deflection method, which avoids errors caused by current flow.

Q177. Work done in raising a box depends on

• A. How fast it is raised
• B. The strength of the person raising the box
• C. The height it is raised to
• D. The weight of the box and the height it is raised to✓

Explanation: Correct. Work done is given by W=mgh, which depends on both the weight of the box (mg) and the height (h)

Q178. In earth's gravitational field, the absolute potential at any point in space is:

• A. (G Me)/2Re
• B. (G mMe)/ReA2
• C. (G Me)/Re✓
• D. (G m Me)/Re

Explanation: The correct answer is (G Me)/Re, where G is the universal gravitational constant, Me is the mass of the Earth, and Re is the distance from the center of the Earth to the point in question. This formula represents the gravitational potential energy per unit mass at a point in the gravitational field of the Earth. The other options are incorrect because they either misrepresent the formula by including unnecessary factors (like 2 or an extra variable) or alter the necessary components of the formula, leading to incorrect expressions for absolute potential energy.

Q179. What physical quantity would result from a calculation in which a potential difference is multiplied by an electric charge

• A. Electric current
• B. Electric energy✓
• C. Electric field strength
• D. Electric power

Explanation: Correct. Energy (W) is given by W=QV, where Q is charge and V is potential difference

Q180. Kinetic energy is the product of two vectors. It is:

• A. Dot product of velocities
• B. Cross product of velocities
• C. Product of mass and velocity
• D. Half product of mass and velocity squared✓

Explanation: Correct. Kinetic energy is given byKE=1/2mv2which is the half product of mass and the square of velocity.

Q181. Which one is a variable capacitor

• A. Ceramic capacitor
• B. Air gap capacitor✓
• C. Variable electrolytic capacitor
• D. Silver capacitor

Explanation: Correct. Air gap capacitors have a variable capacitance, which can be adjusted by changing the separation between the plates.

Q182. The velocity of sound in air is independent of:

• A. Temperature
• B. Pressure✓
• C. Density
• D. Humidity

Explanation: Correct. In an ideal gas, the velocity of sound is given byv= squareroot (γRT/M) which shows that it depends on temperature but is independent of pressure at constant temperature.

Q183. The process of converting AC into DC is called:

• A. Amplification
• B. Rectification✓
• C. Modulation
• D. Detection

Explanation: Correct. Rectification is the process of converting alternating current (AC) into direct current (DC) using diodes.

Q184. The force acting on a body of mass 10 kg is 100 N. The distance covered by the body in 10 seconds, if it starts from rest, is:

• A. 100 m
• B. 500 m✓
• C. 1000 m
• D. 5000 m

Explanation: Explanation:First, find the acceleration: a = F/m = 100 N / 10 kg = 10 m/s².Then, use the kinematic equation: d = ut + (1/2)at². Since the body starts from rest, u = 0.d = 0 + (1/2)(10 m/s²)(10 s)² = (1/2)(10)(100) = 500 m.

Q185. The rest mass of photon is:

• A. One
• B. Infinite
• C. Zero✓
• D. Depends on frequency

Explanation: Explanation:Photons are massless particles. They have energy and momentum due to their motion, but their rest mass is zero.

Q186. The velocity of sound in air at NTP is 332 ms−1. The velocity of sound in vacuum is:

• A. 332 ms−1
• B. 166 ms−1
• C. 88 ms−1
• D. Not defined✓

Explanation: Explanation: Sound waves require a medium to propagate. In a vacuum, there are no particles to carry the sound waves.

Q187. The electric field at a point situated at a distance d from a straight charged conductor is:

• A. Proportional to d
• B. Inversely proportional to d2
• C. Independent of d
• D. Inversely proportional to d✓

Explanation: Inversely proportional to d Explanation: The electric field due to a long, straight charged conductor is inversely proportional to the distance from the conductor (E ∝ 1/d).

Q188. The number of turns in the primary and secondary coils of a transformer are 10 and 2000 respectively. If the current in the primary is 1.0 A, What would be the current in the secondary

• A. 0.05 A
• B. 0.5 A
• C. 5.0 A
• D. 0.005 A✓

Explanation: Explanation: For an ideal transformer, Np/Ns = Is/Ip. Is = Ip * (Np/Ns) = 1.0 A * (10/2000) = 1.0 A * 0.005 = 0.005 A.

Q189. The energy of each photon with frequency 1.2×10^14 Hz will be:

• A. 7.9×10^−48 J
• B. 7.9×10^−40 J
• C. 7.9×10^−28 J
• D. 7.9×10^−19 J✓

Explanation: Explanation:E = hf, where h is Planck's constant (6.63 × 10^-34 J·s) and f is frequency. E = (6.63 × 10^-34 J·s)(1.2 × 10^14 Hz) = 7.956 × 10^-20 J ≈ 7.9 × 10^-19 J

Q190. The magnitude of the vector product of two vectors is √3 times the scalar product. The angle between the two vectors is:

• A. 45°
• B. 90°
• C. 30°
• D. 60°✓

Explanation: Explanation:|A × B| = AB sin(θ) and A·B = AB cos(θ).AB sin(θ) = √3 AB cos(θ).tan(θ) = √3, so θ = 60°.

Q191. Analyze the cause-and-effect relationship between the statements:I. The glaciers at the poles of the earth are melting at a fast rate.II. In recent times, there has been a substantial increase in the intensity of sunlight and volcanic eruptions.

• A. Statement (I) is the cause and statement (II) is its effect.
• B. Statement (II) is the cause and statement (I) is its effect.✓
• C. Both statements (I) and (II) are independent causes.
• D. Both statements (I) and (II) are effects of independent causes.

Explanation: Correct. Increased sunlight and volcanic activity contribute to global warming, which leads to glacier melting.

Q192. Read the following statement, assuming everything in the statement to be true. Then decide which of the given suggested courses of action logically follows beyond a worth pursuing. Statement: An invigilator catches a student peeking at another student's worksheet in a school exam. Courses of Action: I. Immediately cancel both of the students' exams and remove them from the school. II. Change the student's position to one which is more secluded and give them a warning.

• A. I only
• B. II only✓
• C. Both I and II
• D. Neither I nor II

Explanation: Correct. Changing the student's position and giving a warning is a reasonable action. It prevents further misconduct while allowing the student a chance to correct their behavior.

Q193. Which part of the sentence carries an error?There were five active workers and three lazy one in the factory.

• A. There were
• B. Five active workers
• C. In the factory
• D. And three lazy one✓

Explanation: The error is in "three lazy one." Since "three" is plural, "one" should be "ones."

Q194. Choose the correct option to complete the given analogy:A lion is to a pride as a goose is to a _ .

• A. Feather
• B. Flock✓
• C. Gander
• D. Pot

Explanation: The correct option is Flock.A group of geese is called a "flock," just like a group of lions is a "pride."

Q195. Fill in the blank with the correct word:Neither the invaders who were invading _ happening.

• A. Or
• B. Nor✓
• C. Not
• D. None

Explanation: The correct answer is Nor. In English grammar, 'neither' is used to indicate a negative alternative, and it is always paired with 'nor' to connect two negative clauses. In the sentence provided, 'Neither the invaders who were invading...nor...' maintains the grammatical structure needed to express that both the subjects are excluded from the action. The other options are incorrect because 'Ir' is not a conjunction, 'Not' lacks the necessary correlative structure, and 'None' does not serve as a conjunction in this context.

Q196. Choose the sentence with an appropriately structured phrase:

• A. They got married on a dull, sunny day in June.
• B. They got married on a cloudy, sunny day in June.
• C. They got married on a bright, sunny day in June.✓
• D. They got married on a damp, sunny day in June.

Explanation: Correct. "Bright" and "sunny" are complementary, making this phrase well-structured.

Q197. Observe the pattern and select the next term in the series. TEAM, TAME, TMEA,

• A. MUET
• B. TEAM
• C. TAUM
• D. MEAT✓

Explanation: The correct option is MEAT.Explanation: The given sequence rearranges the letters of "TEAM" systematically."TEAM" → "TAME" (Swapping 'E' and 'A')"TAME" → "TMEA" (Swapping 'A' and 'M')"TMEA" → "MEAT" (Swapping 'T' and 'M')Following this pattern, the next term in the series is MEAT.

Q198. All children are silly people. Some silly people are rich people. All rich people are big shots. Which of the following conclusions are NECESSARILY TRUE?CONCLUSIONS:I. Some silly people are children.II. Some rich people are children.III. Some silly people are big shots.

• A. I and III✓
• B. II
• C. II and III
• D. I and II

Explanation: Let's analyze each conclusion one by one: I. "Some silly people are children." This conclusion is necessarily true based on the given statements. While it's mentioned that "All children are silly people," it implies that there are some silly people who are children. It's possible that there are other silly people who are not children. II. "Some rich people are children." This conclusion is not necessarily true based on the given statements. Although it's mentioned that "Some silly people are rich people" and "All children are silly people," it doesn't necessarily mean that there are rich people who are children. There could be rich people who are not children. III. "Some silly people are big shots." This conclusion is necessarily true based on the given statements. It's stated that "Some silly people are rich people" and "All rich people are big shots." Therefore, it's logically consistent that there must be some silly people who are big shots. So, the correct conclusion is: A. I and III I and III are necessarily true based on the given statements, while II is not necessarily true.

Q199. Read the following and choose the correct answer.X, Y and Z are three whole numbers less than 31 but greater than 23. X is a prime number. Y is the largest odd number smaller than 31. Z is the smallest even number?

• A. X is 31, Y is 29 and Z is 24
• B. X is 29, Y is 29 and Z is 24✓
• C. X is 23, Y is 29 and Z is 24
• D. X is 27, Y is 31 and Z is 26

Explanation: According to the given questionOption A: 31 is not a prime numberOption BThis is a correct optionOption C:Z is 24 which is not a smallest even numberOption D:As 27 which is not a prime number and Z is 26 which is not a smallest even number so, this option is incorrect.

Q200. Five cities P, Q, R, S and T are connected by different modes of transport as follows:P and Q are connected by boat as well as by railS and R are connected by bus and by boatQ and T are connected only by airP and R are connected only by boatT and R are connected by rail and by busWhich mode of transport would help one to reach R starting from Q but without changing mode of transport?

• A. Boat✓
• B. Rail
• C. Bus
• D. Air

Explanation: The correct answer is Boat because the only direct route from Q to R is via boat, which can be taken from P. The connection is established as follows: Q can reach P by either boat or rail, and from P, it can reach R directly by boat. The other options are incorrect because:Rail: Q can reach P by rail, but there's no further rail connection to R.Bus: While there is a bus connection between S and R, it cannot be accessed directly from Q without a change in transport.Air: Q is connected to T by air, but there is no subsequent connection from T to R.Therefore, the only viable transport option to reach R from Q without changing is by Boat.