Sindh Mcat Nts 2003 — Solved Past Paper with Answers

Q1. She _an accident last year, she _ driven since.

• A. has , has not
• B. had , has not✓
• C. have , had not
• D. had , had not

Explanation: In the first blank they are talking about the past , so we will put "had". In the second blank, they talked about the present situation so we will put "has not". Hence option B is correct.

Q2. He _a prize last year, since he_his personality.

• A. wins, has change
• B. wins, has changed
• C. won, has change
• D. won , has changed✓

Explanation: The first half of the sentence points towards an event that took place in the past, so the third form of the verb will be used i.e won.Second half if the sentence must contain a verb with third form but with a has proceeded it because it is pointi g to an action that had started in the past but is still going.So, option D is correct.

Q3. He did _ excellent job while among us.

• A. a
• B. an✓
• C. the
• D. None of these

Explanation: Since excellent gives a vowel sound, we will put "an" before it."a" is used when a consonant sound exceeds."The" is used when we point to a definite person or thing.Here all the options except B are incorrect.

Q4. Flee is a/an:

• A. Insect✓
• B. Bird
• C. Animal
• D. None of these

Explanation: Flee is a small insect. You can see it in the picture below.

Q5. Wander means :

• A. Foolish
• B. Slow
• C. Roam✓
• D. Fly

Explanation: Wander means to depart or roam around . E.g;He was wandering at night.So option C is correct.Options A, B and D are irrelevant.

Q6. Synonym for "novice" is :

• A. Doyen
• B. Expert
• C. Professional
• D. Neophyte✓

Explanation: Novice is a person who is inexperienced or a beginner. Neophyte means the same.Doyen means a respectable person.Expert is a skillful person.Professional refers to a pro person.Hence options A, B and D are incorrect.

Q7. Synonym for "incendiary" is :

• A. Motive
• B. Goad
• C. Arsonist✓
• D. Insensitive

Explanation: Incendiary means inflammatory; tending to stir up a conflict. Option C fits perfectly because an arsonist is a person who starts a fire and is responsible for it.Motive(reason), goad(provoke), and insensitive cannot be the synonyms for arsonist.So options A, B and D are incorrect.

Q8. Synonym of "incense" is :

• A. Cause
• B. Exciting
• C. Irritated✓
• D. Enrage

Explanation: Incense means to provoke, exasperate. Option C says irritated which fits here perfectly, hence it is the correct answer.Cause , exciting or enrage(making angry) cannot be the synonyms for incense . So options A, B and D are incorrect.

Q9. The antonym for "extol" is :

• A. Defame✓
• B. Alternate
• C. Conceal
• D. Refrain
• E. Reject

Explanation: Extol means to praise or laud someone or something. Its opposite is to blame or criticise. Hence option A, i.e defame is correct. Option B contains Alternative which could not be the antonym of extol.Similarly options C , D and E also cannot be the antonyms for extol as they are not presenting the same idea as defame .

Q10. Antonym of "Efface" is :

• A. Trust
• B. Restore✓
• C. Embody
• D. Contract
• E. Appreciate

Explanation: Efface means to erase something or rub out. Its opposite is to build or construct. Hence option B i.e restore is the antonym of efface. Option A (trust) , option C (embody) , option D (contract) , and option E (appreciate) could not be the antonyms for Efface.

Q11. Human liver secretes _.

• A. Bile✓
• B. Pepsin
• C. Vitamin D
• D. Cholecystokinin

Explanation: Bile is secreted by the liver and is stored in the gallbladder. Option B is incorrect because Pepsin is a protease enzyme that is secreted by the chief cells (zymogen cells) of the gastric glands in its inactive form pepsinogen.Option C is incorrect because Vitamin D is produced in the skin through sunlight (UV radiation) and it is also obtained through diet (milk, fish liver oil,etc)Option D is incorrect as Cholecystokinin is a hormone that is released by the small intestine. It stimulates the digestion of proteins and fats in the small intestine.

Q12. Dalbergia sisso is botanical name of _.

• A. Sesbania
• B. Edible pea
• C. Sweet pea
• D. Red wood✓

Explanation: Dalbergia sisso is the botanical name of Red wood.Option A is incorrect because Sesbania is a genus belonging to the family Fabaceae (pea family)Option B is incorrect because Edible pea’s botanical name is Pisum sativum.Option C is incorrect as Lathyrus odoratus is the botanical name of sweet pea.

Q13. Digestion of cell contents by lysosomes Is termed as _.

• A. Endocytosis
• B. Autophagy✓
• C. Immunalysis
• D. Exocytosis

Explanation: The process by which unwanted structures within the cell are engulfed and digested within the lysosomes is called autophagy.

Q14. Coniferous forests are found at _.

• A. High altitudes & latitudes✓
• B. Low altitude & latitudes
• C. High longitudes & latitudes
• D. High altitude & longitude

Explanation: Coniferous forests consist mostly of conifers, which are trees that grow needles instead of leaves and cones instead of flowers. Conifers tend to be evergreen—they bear needles all year long. These adaptations help conifers survive in areas that are very cold or dry. Coniferous forests are located at higher altitudes and latitudes.

Q15. Fungi cause many diseases in humans such as _.

• A. Elephantiasis
• B. Leishmaniasis
• C. Warts
• D. Monalisis✓

Explanation: Option D is correct as Moniliasis, also known as Candidiasis, is an infection caused by a fungi, Candida albicans.

Q16. Depletion of ozone layer is due to CFC which release _.

• A. Cl atoms✓
• B. CO
• C. F
• D. CCl4

Explanation: CFCs do not easily react with other substances. In fact, they break up only through sunlight, which divides their molecules, causing the release of chlorine (Cl). Once the chlorine is released, it is able to react with ozone (O3), to form chlorine monoxide (ClO) and oxygen (O2).

Q17. Fertilization in mammals takes place in _.

• A. Uterus
• B. Ovary
• C. Vagina
• D. Fallopian tube✓

Explanation: Egg is released into fallopian tubes by one of the ovaries in females, if sperm is reached in the fallopian tube at the time of ovulation, fertilisation takes place there.

Q18. Extremely small amount of yolk are called _.

• A. Alecithal
• B. Polylecithal
• C. Oligolecithal✓

Explanation: An egg with a small quantity of evenly distributed yolk is called an oligolecithal egg. Oligo means low or too little. As the question mentions the word extremely small, we can infer oligolecithal to be the correct answer.

Q19. Ectoderm give rise to _.

• A. Muscular system
• B. Vascular system
• C. Nervous system✓
• D. Digestive system

Explanation: The nervous system arises from ectoderm.

Q20. Science of aging is called _.

• A. Palaeontology
• B. Entomology
• C. Gerontology✓
• D. Parasitology

Explanation: Gerontology is the study of the process of aging and the problems related to old age.

Q21. The organism in which both extracellular and Intracellular digestion takes place is _.

• A. Hydra✓
• B. Amoeba
• C. Paramecium
• D. Planaria

Explanation: Digestion in Hydra is both extracellular as well as intracellular. Digestion in Hydra takes place within the gastrovascular cavity. Digestion in this animal gets completed in two stages - extracellular digestion and intracellulardigestion. First, digestive juices are secreted by the cells of the inner lining of the cavity, which leads to the killing of the engulfed prey. At this point, the digestive enzymes start their action on the food and results in their digestion. The digestive process occurring inside the gastrovascular cavity is known as extracellular digestion. In the next stage, the tiny fragments of food are absorbed by the nutritive cells present in the lining of the gastrovascular cavity. They are further digested within food vacuoles. This type of digestion is called intracellular digestion.

Q22. Hydra and corals are classified in _.

• A. Coelenterate✓
• B. Porifera
• C. Echinodermata
• D. Mollusca

Explanation: Hydra and corals are the examples of organisms belonging to Phylum cnidaria(coelenterata).

Q23. Snail is included in the class _.

• A. Gastropods✓
• B. Bivalvia
• C. Arachnida
• D. Myriapoda

Explanation: Snail is one of the organisms belonging to the Class Gastropoda.

Q24. Ascaris lives in the _ of man.

• A. Intestine✓
• B. Liver
• C. Blood
• D. Bladder

Explanation: Ascaris is an intestinal parasite of humans. It is the most common human worm infection. The larvae and adult worms live in the small intestine and can cause intestinal disease.

Q25. Sea star moves with the help of _.

• A. Pseudopodia
• B. Tube feet✓
• C. Cilia
• D. Flagellum

Explanation: An echinoderm(sea star) moves by using many tube feet. Tube feet are small, delicate projections attached along the side of a water-filled tube called a radial canal. Tube feet extend through the small holes in the skeleton to the outside.

Q26. Pike and trout are:

• A. Jawless fishes
• B. Bony fishes
• C. Cartilaginous fishes✓
• D. All of the above

Explanation: Trout, goldfish, tuna, clownfish, pike and catfish are all kinds of bony fishes.

Q27. Defensive cells of cnidarians are called _.

• A. Nematocysts✓
• B. Gonocytes
• C. Oocytes
• D. Gastrocytes

Explanation: The animals of the phylum Cnidaria show the presence of stinging cells called the cnidocytes. These cells have nematocysts that release the toxin, when they catch the prey or when something touches their body. So these are both defensive and offensive cells.

Q28. Growth of pollen tube towards ovary is an example of _ movement.

• A. Phototropic
• B. Chemotactic✓
• C. Sensory
• D. Mechanical

Explanation: Chemotactic movement leads the pollen grains to the embryo sac. It means that the pollen grain is moving towards the ovary in response to a chemical stimulus. Chemotactic movement causes the pollen grains to reach the embryo sac and results in fusion, which is also called syngamy. The pollen tube grows from the tip of pollen grain.

Q29. Cells which are absent in gymnosperms but present In angiosperms are _.

• A. Vessels✓
• B. Tracheids
• C. Collenchyma
• D. Parenchyma

Explanation: Most gymnosperms lack vessel elements in their xylem, unlike angiosperms(flowering plants) which have both vessels and tracheids. The vessel element plays an important role in the flowering plants as they require more amount of water for their growth than gymnosperms (non-flowering plants)

Q30. Under secretion of thyroxine in infants causes _.

• A. Cretinism✓
• B. Dwarfism
• C. Gigantism
• D. Osteoporosis

Explanation: Cretinism or congenital hypothyroidism is generally characterised by stunted growth and mental retardation in infants due to under secretion of thyroxine. Short stature (dwarfism). Mild neurological impairment with reduced muscle tone and coordination. Hearing and speech defects.

Q31. Protein synthesis takes place in _.

• A. Ribosomes✓
• B. Mitochondria
• C. Mesosomes
• D. Golgi bodies

Explanation: Ribosomes are the organelles concerned with protein synthesis.

Q32. Major oil & gas fields in Pakistan are located in _.

• A. Potohar
• B. Gholki
• C. D.I khan✓
• D. FATA

Explanation: Dera Ismail Khan also presents investment opportunities for local and foreign firms in the Oil & Gas sector in"D.l.Khan East, West Block& Khushal Block".

Q33. The humidity in air is inversely proportional to _ process in plants.

• A. Transpiration✓
• B. Respiration
• C. Photosynthesis
• D. None of the above

Explanation: The difference in water potential decreases between empty spaces of leaf and air when humidity is high, so transpiration rate decreases. Hence, humidity is inversely proportional to transpiration.

Q34. Shrinkage of protoplasm from cell wall under hypertonic solution is called _.

• A. Plasmolysis✓
• B. Endosmosis
• C. Proteolysis
• D. Torsion

Explanation: Plasmolysis is a typical response of plant cells exposed to hyperosmotic stress. The loss of turgor causes the violent detachment of the living protoplast from the cell wall. The plasmolytic process is mainly driven by the vacuole. Plasmolysis is reversible (deplasmolysis) and characteristic toliving plant cells.

Q35. Acetyl CoA loses CoA and combines with a 4-Carbon compound which is:

• A. Oxaloacetic acid✓
• B. Citric acid
• C. Succinic acid
• D. Malic acid

Explanation: Acetyl CoA after losing CoA, combines with oxaloacetic acid (4C compound), the first member of Krebs cycle.

Q36. Product of anaerobic respiration in animals is _.

• A. Pyruvic acid
• B. Lactic acid✓
• C. Alcohol
• D. NADPH-2

Explanation: Anaerobic respiration refers to cellular respiration occurring in absence of oxygen.Anaerobic respiration is also referred to as fermentation.When in absence of oxygen, the glucose molecule is broken down to produce alcohol and energy it is referred to as anaerobic respiration.It is majorly observed in lower groups of animals and fungi.It happens in the cytoplasm of the cell.Instead of ethanol (alcohol), animal cells produce lactic acid during anaerobic respiration.Some lower groups of animals and muscular cells under stress conditions perform anaerobic respiration. It is done for the rapid synthesis of energy to fulfil cellular demand.Lactic acid is an end product of anaerobic respiration in animals.

Q37. Seedless fruits which grow without fertilization are called _.

• A. Angiosperms
• B. Patthenocarpus✓
• C. Ovulatory
• D. Messangial

Explanation: Many varieties of Citrus species can naturally set fruits without seeds. This phenomenon, called parthenocarpy, is defined as the ability to produce fruits without fertilisation of the ovules and, therefore, without seeds development. Parthenocarpy depends on a genetic factor that favours the maintenance of a relatively high hormone(Auxin) level in the ovary during the anthesis and immediately after it, regardless of pollination and fertilisation. Many species and cultivars produce fruit that either lack seeds or have no viable seeds. Parthenocarpy is common for the horticultural varieties of banana, pineapple, cucumber, tomatoes, figs, oranges, grapes, kiwi, blackberry, pepper, etc. Parthenocarpy is a genetically inherited trait, and different cultivars (orecotypes) differ in their potential to formparthenocarpic fruit.

Q38. If temperature is reduced to near or below freezing point enzymes become:

• A. Denatured
• B. Dormant✓
• C. Renatured
• D. All of the above

Explanation: Near or below the freezing point enzymes become dormant(inactive) and can be activated again if temperature is increased.

Q39. The feathers which help the birds in flying are:

• A. Quil feathers
• B. Hair feathers
• C. Down feathers
• D. Plumulae✓

Explanation: Plumulae is also called down feathers,they help birds in flying. They are soft and fluffy. Down feathers help insulate birds by trapping air. Some birds, such as herons,have special down feathers called powder down which breaks up into a fine powder.

Q40. Sugar is stored in the liver as:

• A. Starch
• B. Glycogen✓
• C. Maltose
• D. Cellulose

Explanation: Glucose or sugar is converted into glycogen ( a polysaccharide) for storage in animals. It is stored in the liver. This glycogen is broken down into glucose when required (when the body requires energy).

Q41. Platinum or polonium are used as catalysts in:-

• A. Haber process
• B. Contact process
• C. Oxidation of NH3✓

Explanation: Platinum and polonium are used as the catalyst in oxidation of NH3 (Ostwald Process).

Q42. For "f" orbital value of l is:-

• A. 3✓
• B. 2
• C. 0
• D. 1

Explanation: value of l (azimuthal quantum no.) for orbitals is:s=0p=1d=2f=3

Q43. Characteristic of number 1000 (in log) is:-

• A. 3✓
• B. 2
• C. 4
• D. 0

Explanation: Consider 10^0 = 1. We say log 1 to the base 10 = 0.Consider 10^1 = 10. We say log 10 to the base 10 =1So what about the log of numbers which liebetween 1 and 10? i.e., say log 7. It should bebetween 0 and 1. i.e., 0._Now consider 10^2= 100. Hence we say log 100 tothe base 10 = 2So what about the log of numbers which liebetween 10 and 100? Say log 36.9. It should bebetween 1 and 2.Now consider 10^3 = 1000. Hence we say log 1000 tothe base 10 =3

Q44. Petrie Curie and Maire Curie isolated a new radioactive element which was:

• A. Radium✓
• B. Thoriam
• C. Uranium

Explanation: Radium was discovered by Marie And his husband Pierre Curie on 21December 1898, in a uraninite(pitchblende) sample from Jáchymov. While studying the mineral earlier, the Curies removed uranium from it and found that the remaining material was still radioactive.

Q45. Faraday's experiment leads to the discovery of:

• A. Electron✓
• B. Positron
• C. Nucleus
• D. Proton

Explanation: Faraday's law describes the production of electric current due to change in magnetic flux, electronic current proves the presence and existence of electrons.

Q46. S.I unit of viscosity is:-

• A. Nsm
• B. Nsm-2✓
• C. Ns-1 m2

Explanation: The dimensions of dynamic viscosity are force × time ÷ area. The unit of viscosity, accordingly, is newton-second per square metre, which is usually expressed as pascal-second in SI units.

Q47. 1 poise can be fined as:-

• A. 1 gm/m
• B. 1 gm/cm✓
• C. 1 gm/mm
• D. None of these

Explanation: 1 Poise [P] =1 g/(cm s) .So it can be found in terms of g/cm

Q48. Excited state of C atom can be represented as:

• A. 1s² 2s¹ 2px¹ 2py¹ 2px¹
• B. 1s1 2s¹ 2px¹ 2py¹ 2pz¹
• C. 1s² 2s¹ 2px¹ 2py¹ 2pz¹✓
• D. None of these

Explanation: The excited-state electronic configuration of a carbon atom is 1s² 2s¹ 2px¹ 2py¹ 2pz¹ i.e, the one electron from the s orbital gets excited to the p orbital by absorbing some energy.

Q49. Except sucrose all oligosaccharides are :-

• A. Reducing✓
• B. Non-reducing
• C. None
• D. Both of these

Explanation: For a sugar to be reducing there must be a free OH group on C-1 of the sugar that is in ring e.g in following structure of maltose right monosaccharide has free OH on C-1(it is in ring).But if we see sucrose no free OH is present in C-1 of the ring.

Q50. Ketone can be oxidized by using:

• A. Tollen's reagent
• B. Fehling solution
• C. K2Cr2O7 with H2SO4✓
• D. K2Cr2O7 with HNO3

Explanation: Because ketones do not have hydrogen atom attached to their carbonyl, they are resistant to oxidation. Only very strong oxidising agents such as Potassium dichromate solution along with sulphuric acid oxidise ketones.

Q51. (BeH2)n is an example of:

• A. Border line Hydride
• B. Covalent Hydride
• C. Ionic hydride
• D. Polymeric hydride✓

Explanation: Polymeric Hydrides are the Hydrides of Beryllium. In polymeric Hydrides, a large number of BeH2 units are joined by hydrogen bonding to produce a long chain of BeH2.The general representation of such chains are:-(BeH2)nWhere "n" is any positive number.Option A is incorrect as borderline hydrides are the hydrides of group 11 and group 12 of the periodic table and indium and thallium. Their properties are intermediate to covalent hydrides and ionic hydrides.

Q52. S- block elements are powerful:

• A. Oxidizing Agents
• B. Reducing agents✓
• C. None
• D. Both

Explanation: As s block elements have largest atomic radius, and low ionization energy so they can easily get oxidised by losing electrons due to less attraction between nucleus and valence electrons, thereby reducing other elements, acting as a reducing agent.

Q53. "The electrons are filled to the orbitals of lowest energy in sequence, two to each orbital", this is statement of:-

• A. Pauli’s exclusion principle
• B. Aufbau Principle✓
• C. (n+l) Rule
• D. Hund's Rule

Explanation: The aufbau principle, states that in the ground state of an atom or ion, electrons fill subshells of the lowest available energy, then they fill subshells of higher energy. For example, the 1s subshell is filled before the 2s subshell is occupied.

Q54. Anomalous behaviour & high boiling point of H2O is due to:

• A. Strong covalent bond
• B. Hydrogen bonding✓
• C. Ionic bonding
• D. Wander Val forces

Explanation: Hydrogen bonding in H2O is responsible for its high boiling point and anomalous behaviour. H2O has the tendency of forming upto 4 hydrogen bonds.

Q55. Two substances having same crystal structure are said to be:-

• A. Polymorphous
• B. Isomorphous✓
• C. Homomorphous
• D. Synmorphous

Explanation: Iso means same, morph means shape.Isomorphism means crystals having same shape.

Q56. Molarity of 10 gm of NaOH dissolved in 1dm3 of solution is:-

• A. 7 M
• B. 0.25 M✓
• C. 10 M
• D. 20 M

Explanation: Mass of NaOH= 10 Molar Mass of NaOH= 40Moles = 10/40 = 0.25 moles Molarity = no of moles of solute / volume in dm3M= 0.25/1 = 0.25 M

Q57. Which one is correct:-

• A. Glass is not a true solid b/c molecules are not arranged in definite manner✓
• B. Glass ts a true solid b/c molecules are not arranged in a definite manner
• C. Both of these
• D. None of these

Explanation: Graphite forms layers , it don't have orderly arrangement of atoms in 3 dimensional.

Q58. A solution which tends to resist change in pH is:-

• A. Baric solution
• B. Basic solution
• C. Buffer solution✓
• D. Neutral solution

Explanation: Buffer action in general is defined as the ability of the buffer solution to resist the changes in pH value when a small amount of an acid or a base is added to it.

Q59. A substance which does not lower energy of activation but combines with reactant molecule is called:

• A. Catalyst
• B. Negative catalyst✓
• C. Positive catalyst
• D. None

Explanation: The catalyst that decreases the rate of reaction is known as a Negative catalyst.The rate of reaction decreases by increasing the activation energy which further decreases the number of reactant molecules or the molecules performing effective collision.

Q60. Which one is incorrect:

• A. Alpha particles are positively charged
• B. Alpha particles are helium nuclei
• C. Alpha particles are neutral
• D. Alpha particles move towards anode✓

Explanation: Option D is correct as alpha particles being positively charged particles do move towards the anode (positive electrode).

Q61. Which one shows alpha decay :

• A. 2XA ➡️ + 3He4
• B. 2XA ➡️ + 2He4✓
• C. 2XA ➡️ + 3He4
• D. 2XA ➡️ + He4

Explanation: In alpha decay atomic mass is decreased by 4 and atomic number is decreased by 2.

Q62. MgCl2 is surrounded by _ number of water molecules :

• A. 2
• B. 6✓
• C. 5
• D. 8

Explanation: Mg have empty subshells , So 6 water molecules can surround it forming a hydrated compound Magnesium chloride hexahydrate having six molecules of water of crystallisation.

Q63. Gas constant "R" is independent of :

• A. Pressure of gas
• B. Volume of gas
• C. Nature of gas✓
• D. Temperature

Explanation: For one mole of gas R=PV/TFrom this equation we see that R is independent of the nature of gas.

Q64. Which has shortest C-C bond length:

• A. C2H2✓
• B. C2H4
• C. CCl4
• D. C2H5OH

Explanation: In Ethyne(C2H2) C-C bond is the shortest bcz both C atoms form a triple bond with each other increasing bond energy thereby decreasing bond length. The bond length in alkynes is 1.20 Angstroms. Since all these bond lengths are greater than the corresponding bond length of alkyne , hence all options except option A are incorrect.

Q65. Cyclohexane is an example of :

• A. Acyclic Aromatic Compound
• B. Alicyclic Aromatic Compound
• C. Alicyclic Homocyclic Compound✓
• D. None of the above

Explanation: Alicyclic are those compounds that do not contain an aromatic character. Cyclohexane is alicyclic as well as Homocyclic because it contains no other atoms except carbon.

Q66. Which of the following is an example of decrease in entropy :

• A. Evaporation of water
• B. Sublimation of ice
• C. Both
• D. None✓

Explanation: Whenever a substance is converted to gas, entropy increases. When water evaporates, entropy increases . Also when ice is directly converted to steam, entropy increases .

Q67. Which indicator has green colour in neutral solution :

• A. Phenolphthalein
• B. Universal indicator✓
• C. Methyl Orange
• D. Acid-Base indicator

Explanation: A universal indicator is a pH indicator made of a solution of several compounds that exhibits several smooth colour changes over a wide range pH values to indicate the acidity or alkalinity of solutions.

Q68. An example of covalent hydride is :

• A. NaH
• B. SrH2
• C. AsH3✓
• D. Both B and C

Explanation: AsH3 is a covalent hydride so option D is correct.

Q69. Which is the most basic of the following oxides:

• A. Na2O✓
• B. BaO
• C. As2O3
• D. Al2O3

Explanation: Na2O is the most basic oxide. This is because it contains the oxide ion, O2-, which is a very strong base with a high tendency to combine with hydrogen ions. So option A is correct.

Q70. Corrosion of a metal produces :

• A. Chloride
• B. Sulphate
• C. Oxide✓
• D. Nitrite

Explanation: Corrosion causes metal to get oxidised in the presence of oxygen. This process never produces chlorides , nitrites or sulphites.So all the options except C are incorrect.

Q71. A car starts from rest and gains an acceleration of 4m/s2. Find the final velocity after 5 sec.

• A. 25 m/s
• B. 1.5 m/s
• C. 20 m/s✓
• D. 15 m/s

Explanation: a=4m/s2 , t=5 sec As the car starts from rest so, vi=0m/s Using 1st Equation of motion :vf = 0 + (4x5)vf = 20m/s

Q72. 1kwh =_ :

• A. 36 x 106 J
• B. 36 x 105 J✓
• C. 3.6 x 10-5 J
• D. 3.6 x 10-6 J

Explanation: 1 kilowatt hour is the energy produced by 1 kilowatt power source in 1 hour. 1kWh = 1kW x 1 hour 1kWh = 1000 x 60 min x 60 sec (1 k=1000 , 1hr = 60 mins x 60 sec) → 1kWh = 3.6 x 10^6By shifting the decimal to to right side: 1kWh = 36 x 10^6-1J 1kWh = 36 x 10^5 JHence option B is correct.

Q73. A field in which work done along a close path is zero is called:

• A. Gravitational field
• B. Conservative field✓
• C. Electric field
• D. Magnetic field

Explanation: In coservative field work done does not depend on the path followed so in a closed loop work done will be zero. While gravitational, electric and magnetic fields are all path dependent, so work done in such fields is never zero. Hence all options except B are incorrect.

Q74. Absolute potential energy of a mass "m" lying at surface of earth is :

• A. GMem/Re✓
• B. GMem/Re2
• C. GMe/Re
• D. -ReMem/G

Explanation: The distance between two bodies is equal to the radius of the earth hence option A is correct while all other options are incorrect.

Q75. Work done by centripetal force is:

• A. Maximum
• B. Minimum
• C. Zero✓
• D. Negative

Explanation: As W=Fd cos thetaDuring centripetal force angle between F and d is 90° , so cos 90° =0 , so W=0Hence option C is correct.

Q76. The two vectors are lying at x and y planes. Their resultant will be directed along :

• A. x-axis
• B. y-axis
• C. z-axis
• D. None of these✓

Explanation: The resultant will lie in the x-y plane. It will not be along any of the given axis. Hence, option D is correct.

Q77. A boy standing in a free falling lift drops a ball. The ball will :

• A. Fall down
• B. Goes up
• C. Remain stationary✓
• D. None of these

Explanation: The acceleration of the body "does not" depend on the mass (for freely falling). Hence both man and ball have same acceleration. Hence their velocities at everybpoint would be same. So "Relative" velocity is zero. Hence the ball will always remains stationary as seen by him. So option C is correct.

Q78. The point at which whole mass of the body is concentrated is called:

• A. Centre of gravity✓
• B. Centre of mass
• C. Centre of action
• D. Centre of body

Explanation: The center of gravity is the balance point of an object, also expressed as the point where all the mass appears to be located. So option A is correct.

Q79. Stokes observed that an upward retarding force acts on a body falling in liquid is given by :

• A. F = 6πnr2v
• B. F = 6πnrv2
• C. F = 6πnrv3
• D. F = 6πnrv✓

Explanation: According to Stokes Law, the viscous force acting on a body falling under gravity in a viscous fluid with viscosity n is given by F = 6πnrv where vis the velocity and r is the radius of the spherical body. So all the options except D are incorrect.

Q80. Unit of electric intensity is :

• A. J/C
• B. N/C✓
• C. J/kg
• D. N/kg

Explanation: Electric intensity is given as : E = F/q, so the unit will be N/C. Hence option B is correct.

Q81. Alpha particles are:

• A. Hydrogen nuclei
• B. Helium nuclei✓
• C. Oxygen nuclei
• D. None

Explanation: Alpha particles are Helium nuclei that are doubly positively charged (He++).So option B is correct.

Q82. e/m ratio of an electron is :

• A. 1.75x1011 C/kg✓
• B. 1.75x105 C/kg
• C. 1.75x1019 C/kg
• D. None of these

Explanation: e/m = charge of electron/mass if electron e = 1.6022x 10^-19 C m = 9.1093x 10^-31 kgDividing e by m we get 1.758829x 10^11C/kg. Hence the currently accepted value for e/m is 1.758820 x10^11 C/kg. So option A is correct.

Q83. Vector product of a vector by itself is :

• A. Unity
• B. Zero✓
• C. 90°
• D. Depends on the vector

Explanation: The vector product of any vector with itself is zero because the included angle is zero and sin 0° = 0. Thus the vector product of any unit vector, i, j, or k, with itself is zero. Hence, option B is correct.

Q84. The frictional force of a car taking turn on a circular track is equal to :

• A. Centripetal force
• B. Centrifugal force✓
• C. Magnetic force
• D. Gravitational force

Explanation: The centripetal force causing the car to turn in a circular path is due to friction between the tires and the road which is equal to equal to centrifugal force acting on the car.Centrifugal force is the inertial force that pushes the object towards the circumference of the circle. Hence option B is correct.

Q85. 1hp =_Watt :

• A. 750 Watt
• B. 746 Watt✓
• C. 758 Watt
• D. 756 Watt

Explanation: Horse power is used in British calculations and it is equal to 746 Watts. So option B is correct.

Q86. Two forces equal in magnitude , opposite in direction and not acting along same time , constitute a :

• A. Torque
• B. Couple✓
• C. Moment of arm
• D. None

Explanation: Two force that have equal magnitudes, opposite directions and opposite lines of action are called force couples. The vector sum is zero and the moment exerted is the same about any point. Hence all options except B are incorrect.

Q87. Points of zero amplitude are called :

• A. Nodes✓
• B. Antinodes
• C. Both
• D. None

Explanation: A node is a point along a standing wave where the wave has minimum amplitude. For instance, in a vibrating guitar string, the ends of the string are nodes. By changing the position of the end node through frets, the guitarist changes the effective length of the vibrating string and thereby the note played.Hence option A is correct.

Q88. Two waves of same frequency and amplitude travelling in opposite direction give rise to :

• A. Transverse waves
• B. Longitudinal waves
• C. Standing waves✓
• D. Electromagnetic waves

Explanation: Because the observed wave pattern is characterised by points that appear to be standing still, the pattern is often called a standing wave pattern. Such patterns are only created within the medium at specific frequencies of vibration. So option C is correct.

Q89. Two vectors of magnitude 3 & 4 have a resultant of 5. The angle between vectors is :

• A. 90°✓
• B. 45°
• C. 180°
• D. 270°

Explanation: Let the two vectors be P and Q and their resultant vector be R.Let the angle between P and Q be .Given: IP| =3, IQ| =4 and I RI =5unitsMagnitude of resultant vector | R|2=IP| 2+ IQ| 2+2IP| IQI cos theta.:. 5² =3²+4² + 2(3)(4) cos ∅We get cos∅ = 0→ ∅= 90°Hence option A is correct.

Q90. Layer of soap looks coloured due to :

• A. Interference✓
• B. Polarization
• C. Transmission
• D. None

Explanation: The interference colour is produced when the retardation between the waves of the crystal is equal to a whole number of wavelengths corresponding to its complementary colour.So option A is correct while B, C and D are incorrect.

Q91. 8n Young's double slit experiment , two waves interfere constructively , if path difference is :

• A. (m+½) lambda
• B. m lambda
• C. (m-½) lambda
• D. None of these✓

Explanation: Constructive interference occurs whenever the difference in paths from the two slits to a point on the screen equals an integral number of wavelengths (0, À, 2A,). This path difference guarantees that crests from the two waves arrive simultaneously. Hence, option D is correct.

Q92. If length of pendulum becomes four times, time period will be :

• A. T/2
• B. 4T
• C. 2T✓
• D. T/2

Explanation: First of all let us take a look at what a second's pendulum is. It is a pendulum whose time period of oscillations is accurately two seconds. It takes one second to swing forward and another one second to swing backwards. Now let us discuss the term time period. It is the time taken to oscillate one full oscillation of a pendulum or a wave or to complete one full cycle of wave oscillation.it is given by the formula,T = 2π √L/gWhere T is the time period of oscillation, I is the length of the wire used in the pendulum and g is the acceleration due to gravity. Using this equation we can find the relation between time taken for the oscillation and the length of the pendulum. Here as we know g is the acceleration due to gravity which is constant all over the earth. 2π is also a constant. Therefore we can say that time period is directly proportional to squareroot of length of the pendulum. Therefore as the length of the pendulum becomes four times, the time period becomes 2 times.Hence, the answer for this question is option C.Note: If the length of string increases, the pendulum falls farther than now and therefore the period of oscillation will be longer. Also as the amplitude or angle increases, farther the pendulum falls and hence longer will be the period of motion.

Q93. A projectile is launched at an angle theta to the horizontal with initial velocity v. In the absence of air resistance , which one of the following statements is correct?

• A. The horizontal velocity increase during flight.
• B. The horizontal velocity remains constant throughout flight.✓
• C. The horizontal velocity decreases during flight.
• D. Vertical acceleration increases during flight.

Explanation: "If air resistance is ignored , then there is no acceleration in horizontal direction in projectile motion.Hence the particle move with constant velocity in horizontal direction."So option B is correct.

Q94. 228U nucleus differs from 225U nucleus in that it combines three more :

• A. Neutrons✓
• B. Protons
• C. Electrons
• D. Alpha particles

Explanation: Because the atomic number is same for both isotopes , so the number of protons and electrons are the same but the atomic mass is different so they differ by 3 neutrons. Hence, option A is correct.

Q95. Motor operates from a 120 volts electrical source and uses 4 amperes of electrical current. What is the power generated by the motor?

• A. 30 Watt
• B. 42 Watt
• C. 120 Watt
• D. 480 Watt✓

Explanation: Given :Motor operates from a 120-voltelectrical source and uses 4 amperes of currentTo Find:Power generated by the motorSolution:★ P= VIwhere ,• P denotes power•V denotes potential difference• l denotes currentGiven ,• V( P.D) = 120 V• |=4 A:→ P= V|→P= (120) (4)P= 480 V.AP=480 WHence option D is correct.

Q96. The vector quantity in following is :

• A. Distance
• B. Impulse✓
• C. Energy
• D. Temperature

Explanation: The product of vector and scalar is always a vector, so impulse is a vector quantity with S.I. unit kilogram metre per second. In a nutshell, we can say that Impulse is a vector quantity as it has both magnitude as well as direction.Mathematically, impulse is equal to the change of momentum of the body. So option B is correct.

Q97. The angle of projection of projectile for which its maximum height is equal to 1/4th of horizontal range :

• A. 30°
• B. 45°✓
• C. 50°
• D. 70°

Explanation: This option B suggests that if a projectile is launched at an angle of 45 degrees, its maximum height will be equal to 1/4th of the horizontal range. A 45-degree angle of projection often results in the maximum range for a projectile. Refer to the picture below

Q98. Reactions in which heavy nuclei split into nuclei of intermediate mass number are called :

• A. Fusion reaction
• B. Fission reaction✓
• C. Pair production
• D. Pair annihilation

Explanation: Nuclear fission is a reaction in which the nucleus of an atom splits into two or more smaller nuclei. The fission process often produces gamma photons. So the option B is correct.

Q99. Two vectors each of magnitude F make angle 0° and 270° with x-axis. Their resultant is:

• A. 0
• B. 2F
• C. 2/F
• D. F√2✓

Explanation: This option D suggests that the magnitude of the resultant vector is F√2. This is a possibility since when you add two vectors at right angles to each other, the magnitude of the resultant vector is given by the square root of the sum of the squares of the magnitudes of the original vectors. In this case, if the vectors make angles of 0° and 270° with the x-axis, they are at right angles. Refer to the picture below

Q100. Chose the relation which is not correct :

• A. Ampere = Coulomb per second
• B. Volt= Coulomb per joule✓
• C. Ohm= Volt per Ampere
• D. One Coulomb = charge of 6.24x1018 electrons

Explanation: From relation:- V= W/q Volt= Joule per CoulombHence this option is incorrect. So all options are correct except option B.