Correct option is C $0.1 \Omega$ $$ \begin{array}{l} \mathrm{I}=\mathrm{I}_{\mathrm{g}}+\mathrm{I}_{\mathrm{s}} \\ \left(\mathrm{I}-\mathrm{I}_{\mathrm{g}}\right)...

### A galvanometer with resistance gives full scale deflection with a current of . The value of shunt, in order to convert it into an ammeter of 10 ampere range, will be

### Name the type of lens which is used to correct? i) Myopia ii) Hypermetropia.

Concave lens is used to correct myopia and convex lens is used to correct hypermetropia.

### Explain end-on position and broad side-on position of a bar magnet.

Consider a bar magnet of length 2l and pole strength m. Suppose a point P on the axis of the magnet at a distance d from its center. (d –l) is the distance of P form the N-pole of the magnet.

### What is semiconductor?

Semiconductors have a unique set of electrical properties. A conductor is a substance that conducts electricity, while an insulator is a substance that does not conduct electricity.

### Among and species, the hybridisation state of atoms are respectively:

A

B

C

D dsp

Correct option is B $\mathrm{sp}^{3}, \mathrm{dsp}^{2}, \mathrm{sp}^{3}$ As CN $^{-}$is a strong ligand so here pairing happens and dsp $^{2}$ hybridisation (square planar) takes place while...

### Percentage of free space in bcc. Unit cell is- (A) (B) (C) (D)

Answer: Option (A) $32 \%$

### Differentiate between Natality and Mortality.

Answer: Natality: In humans, natality refers to the number of births per unit population per unit time, such as per thousand per year. It increases the population by bringing in new people. It...

### Write a brief note on Emasculation.

Answer: The removal of anthers from a bisexual flower to prevent self-pollination is known as emasculation. This process does not include the female reproductive system. Plant breeders utilise this...

### Q 90. Person with blood group AB is considered as universal recipient because he has: Option A Both A and B antibodies in the plasma. Option B No antigen on the RBC and no antibody in the plasma. Option C Both A and B antigens in the plasma but no antibodies. Option D Both A and B antigens on the RBC but no antibodies in the plasma.

Correct Option: D Solution: A person with blood group AB have both A and B antigens on the RBC but no antibodies in the plasma are considered as universal recipient.

### Q 89. The motile bacteria are able to move by: Option A Flagella Option B Cilia Option C Pili Option D Fimbriae

Correct Option: A Solution: The motile bacteria are able to move with the help of flagella. These are thin filamentous extensions from the rigid cell walls of the bacteria.

### Q 88. The initial step in the digestion of milk in humans is carried out by? Option A Trypsin Option B Rennin Option C Pepsin Option D Lipase

Correct Option: B Solution: Rennin carries out the initial step in the digestion of milk in human beings.

### Q 87. Select the correct option describing gonadotropin activity in a normal pregnant female: Option A High level of FSH and LH facilitate implantation of the embryo. Option B High level of hCG stimulates the synthesis of estrogen and progesterone. Option C High level of hCG stimulates the thickening of endometrium. Option D High level of FSH and LH stimulates the thickening of endometrium

Correct Option: B Solution: In a normal pregnant female high level of hCG (human chorionic gonadotropin) stimulates the synthesis of estrogen and progesterone

### Q 86. Injury localised to the hypothalamus would most likely disrupt: Option A Co-ordination during locomotion Option B Executive functions such as decision making Option C Regulation of body temperature Option D Short term memory

Correct Option: C Solution: the body temperature is regulated by hypothalamus, so any injury to the hypothalamus disrupts the regulation of body temperature.

### Q 85. The shared terminal duct of the reproductive and urinary system in the human male is: Option A Ureter Option B Vas deferens Option C Vasa efferentia Option D Urethra

Correct Option: D Solution: Urethra is the shared terminal duct of the reproductive and urinary system in human males.

### Q 84. Male gametophyte with least number of cells is present in: Option A Funaria Option B Lilium Option C Pinus Option D Pteris

Correct Option: B Solution: In angiosperms, the male gametophyte is reduced to about 2-3 cells and is called a pollen grain. Lilium is an angiosperm that possesses the male gametophyte with the...

### Q 83. Given below is the representation of the extent of global diversity of invertebrates. What groups do the four portions (A-D) represent respectively? A B C D Option A Crustaceans Crustaceans Molluscs Other animal group Option B Molluscs Other animal group Crustaceans Insects Option C Insects Molluscs Crustaceans Other animal group Option D Insects Crustaceans Other animal group Molluscs

Correct Option: C Solution: In the animal kingdom, phylum Arthropoda is the largest with its largest group of insects. The second-largest population is of phylum Mollusca. In the third place is...

### Q 82. Which of the following is a hormone releasing intra uterine device (IUD)? Option A LNG – 20 Option B Cervical cap Option C Vault Option D Multiload 375

Correct Option: A Solution: LNG-20 is a hormone-releasing intrauterine device (IUD). Implantation is prevented by it and it makes the cervix hostile to the sperms.

### Q 81. Which one of the following is wrongly matched? Option A Translation – Using information in m-RNA to make protein. Option B Repressor protein-Binds to operator to stop enzyme synthesis. Option C Operon – Structural genes, operator and promoter. Option D Transcription – Writing information from DNA to t-RNA

Correct Option: D Solution: Transcription is the process of formation of m-RNA from DNA during protein synthesis. It is not writing information from DNA to t-RNA. Thus this statement is incorrectly...

### Q 80. Which one of the following shows isogamy with non-flagellated gametes? Option A Ectocarpus Option B Ulothrix Option C Spirogyra Option D Sargassum

Correct Option: C Solution: Spirogyra shows isogamy with non-flagellated gametes. Isogamy is a form of sexual reproduction which involves gametes of the same morphology, found in most unicellular...

### Q 79. Which of the following is responsible for peat formation? Option A Riccia Option B Funaria Option C Sphagnum Option D Marchantia

Correct Option: C Solution: Sphagnum is responsible for peat formation. Peat is formed because of the incomplete decomposition of the remains of plants growing in waterlogged conditions.

### Q 78. Tubectomy is a method of sterilization in which: Option A Ovaries are removed surgically. Option B Small part of vas deferens is removed or tied up. Option C Uterus is removed surgically. Option D Small part of the fallopian tube is removed or tied up.

Correct Option: D Solution: The process in which a small part of the fallopian tube is removed or tied up is known as tubectomy.

### Q 77. In a population of 1000 individuals, 360 belong to genotype AA, 480 to Aa and the remaining 160 to aa. Based on this data, the frequency of allele A in the population is: Option A 0.5 Option B 0.6 Option C 0.7 Option D 0.4

Correct Option: B Solution: The total number of individuals = 1000 Genotype frequency of AA = 360÷1000 = 0.36 Genotype frequency of aa = 160÷1000 = 0.16 Genotype frequency of Aa = 2(240)÷1000 = 0.48...

### Q 76. Given below is a simplified model of phosphorus cycling in a terrestrial ecosystem with four blanks (A-D). Identify the blanks. A B C D Option A Litterfall producers Rockminerals Detritus Option B Detritus Rockminerals Producers Litter fall Option C producers Litter fall Rock minerals Detritus Option D Rockminerals Detritus Litter fall Producers

Correct option: B Solution: The correct sequence is- – Detritus – Rock minerals – Producers – Litter fall

### Q 75. Transformation was discovered by: Option A Hershey and Chase Option B Griffith Option C Watson and Crick Option D Meselson and Stahl

Correct Option: B Solution: Griffith discovered the transformation. He was performing an experiment on Diplococcus pneumoniae when he discovered transformation

### Q 74. During which phase(s) of cell cycle, amount of DNA in a cell remains at 4C level if the initial amount is denoted as 2C? Option A G1 and S Option B Only G2 Option C G2 and M Option D G0 and G1

Correct Option: C Solution: In the G2 and M phase of the cell cycle, the amount of DNA in a cell remains at 4C level when the initial amount is denoted as 2C. In M-phase, both 4C and 2C of DNA are...

### Q 73. Non-albuminous seed is produced in: Option A Castor Option B Wheat Option C Pea Option D Maize

Correct Option: C Solution: seeds that have no residual endosperm and is completely consumed during the development of the embryo is termed as non-albuminous seed. Non-albuminous seed is produced in...

### Q 72. Dr.F. Went noted that if coleoptile tips were removed and placed on agar for one hour, the agar would produce a bending when placed on one side of freshly cut coleoptile stumps. Of what significance is this experiment? Option A It is the basis for quantitative determination of small amounts of growth promoting substances. Option B It supports the hypothesis that IAA is auxin. Option C It demonstrated polar movement of auxins. Option D It made possible the isolation and exact identification of auxin.

Correct Option: A Solution: The significance of the experiment is that It is the basis for the quantitative determination of small amounts of growth-promoting substances.

### Q 70. If 20 J of energy is trapped at producer level, then how much energy will be available to peacock as food in the following chain? Plant → mice → snake → peacock Option A 0.002 J Option B 0.2 J Option C 0.0002 J Option D 0.02 J

Correct Option: D Solution: Law of 10 percent is applied Energy trapped at producer level, plant = 20 J Energy trapped by mice = 20 x 10% = 2 J Energy trapped by snake = 2 x 10% = 0.2 J Energy...

### Q 69. Archaebacteria differ from eubacteria in: Option A Mode of nutrition Option B Cell shape Option C Mode of reproduction Option D Cell membrane structure

Correct Option: D Solution: Archaebacteria can be differentiated from eubacteria by the structure of the cell membrane. Archaebacteria has a cell membrane that has branched-chain lipids that help it...

### Q 68. An analysis of chromosomal DNA using the southern hybridisation technique does not use: Option A Blotting Option B Autoradiography Option C PCR Option D Electrophoresis

Correct Option: C Solution: southern hybridization technique is a technique for the identification of the size of DNA from the mixture of other similar molecules. It does not use PCR for the...

### Q 67. A marine cartilaginous fish that can produce electric current is Option A Torpedo Option B Trygon Option C Scoliodon Option D Pristis

Correct Option: A Solution. The torpedo is a marine cartilaginous fish that produces an electric current. This is why it is also known as an electric ray.

### Q 66. How do parasympathetic neural signals affect the working of the heart? Option A Heart rate is increased without affecting the cardiac output. Option B Both heart rate and cardiac output increase. Option C Heart rate decreases but cardiac output increases. Option D Reduces both heart rate and cardiac output.

Correct Option: D Solution: Post-ganglionic fibers of the parasympathetic nervous system secrete acetylcholine. This in return decreases the heart rate and cardiac output.

### Q 65. Viruses have: Option A Prokaryotic nucleus Option B Single chromosome Option C Both DNA and RNA Option D DNA enclosed in a protein coat

Correct option: D Solution: Along with proteins, viruses also contain genetic material that can be either DNA or RNA.

### Q 64. Geitonogamy involves: Option A Fertilisation of a flower by the pollen from the same flower. Option B Fertilisation of a flower by the pollen from a flower of another plant in the same population. Option C Fertilisation of a flower by the pollen from another flower of plant belonging to a distant population. Option D Fertilisation of a flower by the pollen from another flower of the same plant.

Correct Option: D Solution: Geitonogamy involves fertilization of a flower by the pollen from another flower of the same plant

### Q 63. Deficiency symptoms of nitrogen and potassium are visible first in: Option A Young leaves Option B Roots Option C Buds Option D Senescent leaves

Correct Option: D Solution: In Senescent leaves deficiency symptoms of nitrogen and potassium are visible first.

### Q 62. Placenta and pericarp are both edible portions in: Option A Banana Option B Tomato Option C Potato Option D Apple

Correct Option: B Solution: Placenta and pericarp are both edible portions in tomatoes. Placenta is the connecting tissue which supplies nutrition to the embryo and pericarp is the remains of the...

### Q 61. Planaria possess high capacity of: Option A Regeneration Option B Alternation of generation Option C Bioluminescence Option D Metamorphosis

Correct Option: A Solution: Planaria is a flatworm that possesses a high capacity for regeneration.

### Q 60. Stimulation of a muscle fibre by a motor neuron occurs at the: Option A Transverse tubules Option B Myofibril Option C Sarcoplasmic reticulum Option D Neuromuscular junction

Correct Option: D Solution: At the neuromuscular junction occurs the stimulation of muscle fibers by a motor neuron. The junction between a motor neuron and the sarcolemma of the muscle fibre is...

### Q 59. Fight-or-flight reactions cause activation of: Option A The kidney, leading to suppression of renin angiotensin-aldosterone pathway. Option B The adrenal medulla, leading to increased secretion of epinephrine and norepinephrine. Option C The pancreas, leading to a reduction in the blood sugar levels. Option D The parathyroid glands, leading to an increased metabolic rate.

Correct Option: B Solution: The adrenal medulla, leading to increased secretion of epinephrine and norepinephrine is activated because of the Fight-or-flight reactions. Epinephrine (adrenaline) and...

### Q 58. To obtain virus-free healthy plants from a diseased one by tissue culture technique, which part/parts of the diseased plant will be taken? Option A Palisade parenchyma Option B Both apical and axillary meristems Option C Epidermis only Option D Apical meristem only

Correct Option: B Solution: To obtain virus-free healthy plants from a diseased one by tissue culture technique, Both apical and axillary meristems of the diseased plant will be taken.

### Q 57. Commonly used vector for human genome sequencing are: Option A BAC and YAC Option B Expression vectors Option C T/A cloning vectors Option D t-DNA

Correct Option: A Solution: BAC and YAC are the commonly used vector for human genome sequencing. BAC stands for Bacterial artificial chromosomes and YAC for Yeast artificial chromosomes.

### Q 56. An aggregate fruit is the one which develops from: Option A Multicarpellary apocarpus gynoecium Option B Complete inflorescence Option C Multicarpellary superior ovary Option D Multicarpellary syncarpous gynoecium

Correct Option: A Solution: An aggregate fruit is the one that develops from Multicarpellary apocarpous. Gynoecium. The presence of one or more carpels that may be free is called apocarpous.

### Q 54. Select the taxon mentioned that represents both marine and fresh water species: Option A Ctenophora Option B Cephalochordata Option C Cnidaria Option D Echinoderms

Correct Option: C Solution: Phylum cnidaria represents both marine and freshwater species, mostly are marine.

### Q 53. A scrubber in the exhaust of a chemical industrial plant removes: Option A Particulate matter of the size 5 micrometer or above Option B Gases like ozone and methane Option C Particulate matter of the size 2.5 micrometer or less Option D Gases like sulphur dioxide

Correct Option: D Solution: Gases like sulphur dioxide are removed by the scrubber in the exhaust of a chemical industrial plant.

### Q 52. Which one of the following fungi contains hallucinogens? Option A Amanita muscaria Option B Neurospora sp. Option C Ustilago sp. Option D Morchella esculenta

Correct Option: A Solution: Amanita muscaria contains hallucinogens. Hallucinogens are medicines to help patients cope with mental illness.

### Q 51. The zone of atmosphere in which the ozone layer is present is called: Option A Mesosphere Option B Stratosphere Option C Troposphere Option D Ionosphere

Correct Option: B Solution: Stratosphere is the zone of atmosphere in which the ozone layer is present.

### Q 50. Which vector can clone only a small fragment of DNA? Option A Yeast artificial chromosome Option B Plasmid Option C Cosmid Option D Bacterial artificial chromosome

Correct Option: B Solution: plasmid can clone only a small fragment of DNA.

### Q 49. Approximately seventy percent of carbon dioxide absorbed by the blood will be transported to the lungs: Option A In the form of dissolved gas molecules Option B By binding to RBC Option C As carbamino haemoglobin Option D As bicarbonate ions

Correct Option: D Solution: Approximately seventy percent of carbon dioxide absorbed by the blood will be transported to the lungs as bicarbonate ions.

### Q 48. Match the following and select the correct answer: a. Centriole I Infoldings in mitochondria b. Chlorophyll Ii Thylakoids c. Cristae Iii Nucleic acids d. Ribozymes Iv Basal body cilia or flagella a b c d Option A i. ii. iv. iii. Option B i. iii ii. iv. Option C iv. iii. i. ii. Option D iv. ii. i. iii.

Correct option: D Solution: Centriole is a basal body. Chlorophyll contains thylakoids. Cristae are infoldings present in the inner layer of mitochondria Ribozymes is a catalytic RNA.

### Q 47. A human female with Turner’s syndrome: Option A Has one additional X chromosome. Option B Exhibits male characters. Option C Is able to produce children with normal husband. Option D Has 45 chromosomes with XO.

Correct Option: D Solution: A human female with turner’s syndrome has 45 chromosomes with XO.

### Q 46. The organisation which publishes the Red List of species is: Option A IUCN Option B UNEP Option C WWF Option D ICFRE

Correct Option: A Solution: IUCN publishes the Red List of species. IUCN stands for International Union of Conservation of Nature and Natural Resources.

### Q 45. Select the correct option: Direction of RNA synthesis Direction of reading the template DNA strand Option A 3’ – 5’ 5’ – 3’ Option B 5’ – 3’ 5’ – 3’ Option C 3’ – 5’ 3’ – 5’ Option D 5’ – 3’ 3’ – 5’

Correct Option: D Solution: The mRNA is synthesized on the DNA template in the direction of 5’ – 3’ and so, successive nucleotides are attached at the 3’–OH end of the growing mRNA strand. The...

### Q 44. Pollen tablets are available in the market for: Option A Breeding programmes Option B Supplementing food Option C Ex situ conservation Option D In vitro fertilisation

Correct Option: B Solution: for supplementing food pollen tablets are available in the market. These tablets are rich in nutrients.

### Q 43. Which one of the following statements is correct? Option A Mango is a parthenocarpic fruit. Option B A proteinaceous aleurone layer is present in maize grain. Option C A sterile pistil is called a staminode. Option D The seed in grasses is not endospermic.

Correct Option: B Solution: Mango is not a parthenocarpic fruit, it is a seeded fruit. A sterile stamen is called a staminode, not a pistil. The seed in grasses is endospermic. So the correct...

### Q 42. Which one of the following statements is not correct? Option A In retina the rods have the photo pigment rhodopsin while cones have three different photo pigments. Option B Retinal is a derivative of Vitamin (C). Option C Rhodopsin is the purplish red protein present in rods only. Option D Retinal is the light absorbing portion of visual photo pigment.

Correct Option: B Solution: Retinal is a not derivative of Vitamin (C), it is a derivative of Vitamin A.

### Q 41. The first human hormone produced by recombinant DNA technology is: Option A Estrogen Option B Thyroxine Option C Progesterone Option D Insulin

Correct Option: D Solution: The first human hormone produced by recombinant DNA technology is insulin. Eli Lilly in 1993, an American company prepared two DNA sequences corresponding to A and B...

### Q 40. Which one of the following is wrong about Chara? Option A Globule and nucule present on the same plant. Option B Upper antheridium and lower oogonium. Option C Globule is the male reproductive structure. Option D Upper oogonium and lower round antheridium.

Correct Option: B Solution: In Chara, male sex organs is round in shape called as antheridium and is located below the female sex organ called oogonium.

### Q 39. The osmosis of a cell kept in water is chiefly regulated by: Option A Vacuoles Option B Plastids Option C Ribosomes Option D Mitochondria

Correct Option: A Solution: Single membrane known as tonoplast bounds the vacuoles. In plants, tonoplasts make the transportation of ions and other materials against concentration gradient into the...

### Q 38. An example of ex situ conservation is: Option A Seed bank Option B Wildlife sanctuary Option C Sacred grove Option D National park

Correct Option: A Solution: An example of ex situ conservation is seed bank. In seed bank seeds of commercially important plants are stored for long periods.

### Q 37. Assisted reproductive technology, IVF involves transfer of: Option A Zygote into the fallopian tube. Option B Zygote into the uterus Option C Embryo with 16 blastomeres into the fallopian tube Option D Ovum into the fallopian tube

Correct Option: A Solution: In in-vitro fertilization, ova from the female and sperms from the husband are collected and induced to form a zygote under certain conditions in the laboratory. After...

### Q 36. The enzyme recombinase is required at which stage of meiosis: Option A Zygotene Option B Diplotene Option C Diakinesis Option D Pachytene

Correct Option: D Solution: at the stage of Pachytene, occurs the requirement of enzyme recombinase

### Q 35. Which one of the following growth regulators is known as ‘stress hormone’? Option A Ethylene Option B GA3 Option C Indole acetic acid Option D Abscisic acid

Correct Option: D Solution: the closure of stomata in the epidermis is stimulated by abscisic acid. It increases the tolerance of plants to various kinds of stresses, hence called as stress...

### Q 34. An alga which can be employed as food for human beings is: Option A Chlorella Option B Spirogyra Option C Polysiphonia Option D Ulothrix

Correct Option: A Solution: Chlorella is a green alga that is employed as food for human beings.

### Q 33. In-vitro clonal propagation in plants is characterised by: Option A Northern blotting Option B Electrophoresis and HPLC Option C Microscopy Option D PCR and RAPD

Correct Option: D Solution: In in-vitro clonal propagation in plants, the gene of interest is amplified by PCR. RAPD is a PCR reaction in which the DNA segments are amplified randomly.

### Q 32. A location with luxuriant growth of lichens on the trees indicates that the: Option A Trees are heavily infested. Option B Location is highly polluted. Option C Location is not polluted. Option D Trees are very healthy.

Correct Option: C Solution: Indicators of air pollution are The lichens. Air provides them their nutrition. So, if a particular area’s air is polluted then lichens also not found in that area. So,...

### Q 31. Match the following and select the correct option: a. Earthworm i. Pioneer species b. Succession ii. Detritivore c. Ecosystem service iii. Natality d. Population growth iv. Pollination a. b. c. d. Option A i. ii. iii. iv. Option B iv. i. iii. ii. Option C iii. ii. iv. i. Option D ii. i. iv. iii.

Correct option: D Solution: a. Earthworm is a detritivore. b. Succession occurs by pioneer species. c. Ecosystem service includes pollination. d. Population growth is affected by...

### Q 30. Anoxygenic photosynthesis is characteristic of: Option A Spirogyra Option B Chlamydomonas Option C Ulva Option D Rhodospirillum

Correct Option: D Solution: There is no release of oxygen in anoxygenic photosynthesis. It can be seen in Rhodospirillum, which traps light energy and stores it as chemical energy.

### Q 29. What gases are produced in anaerobic sludge digesters? Option A Methane, hydrogen sulphide and CO2 Option B Methane, hydrogen sulphide and O2 Option C Hydrogen sulphide and CO2 Option D Methane and CO2 only

Correct option: A Solution: In anaerobic sludge digesters, the bacteria and the fungi present in the sludge are eaten or digested by the other kinds of bacteria which grow anaerobically. They...

### Q 28. At which stage of HIV infection does one usually show symptoms of AIDS? Option A When the infected retro virus enters the host cells. Option B When HIV damages large number of helper T – lymphocytes. Option C When the viral DNA is produced by reverse transcriptase. Option D Within 15 days of sexual contact with an infected person.

Correct Option: B Solution: The helper T-lymphocytes are targeted by the HIV in the blood, causing a decrease in the number of helper T-lymphocytes in the body of the infected person. The infected...

### Q 27. Which one of the following is a non-reducing carbohydrate? Option A Sucrose Option B Lactose Option C Ribose 5 – phosphate Option D Maltose

Correct Option: A Solution: sugars that do not have an OH group attached to the anomeric carbon, are the non-reducing sugars. They are not able to reduce to other compounds. Lactose, ribose 5 –...

### Q 26. Forelimbs of cat and lizard used in walking and forelimbs of whale used in swimming and forelimbs of bats used in flying are examples of: Option A Adaptive radiation Option B Homologous organs Option C Convergent evolution Option D Analogous organs

Correct Option: B Solution: Homologous organs are those organs that are similar in structure and origin but are not similar in function and form. So the forelimbs of cat and lizard used in walking...

### Q 25. Choose the correctly matched pair: Option A Adipose tissue – Dense connective tissue Option B Areolar tissue – Loose connective tissue Option C Cartilage – Loose connective tissue Option D Tendon – Specialized connective tissue

Correct Option: B Solution: Areolar tissues are loose connective tissues with loose arrangements of the cells and the fibers. These cells and fibers are arranged in a semi-fluid ground substance.

### Q 24. Function of filiform apparatus is to: Option A Stimulate division of generative cell Option B Produce nectar Option C Guide entry of pollen tube Option D Recognise the suitable pollen at stigma

Correct option: C Explanation: The function of guiding the entry of the pollen tube into the synergid is carried out by the filiform apparatus.

### Q 23. A few normal seedlings of tomato were kept in a dark room. After a few days they were found to have become white-colored lime albinos. Which of the following terms will you use to describe them? Option A Embolised Option B Etiolated Option C Defoliated Option D Mutated

Correct option: B Explanation: Etiolation is a process in which the flowering plants are grown in partial or complete absence of light characterized by the long and weak stem and smaller, and sparse...

### Q 22. A man whose father was colour blind marries a woman who had a colour blind mother and a normal father. What percentage of male children of this couple will be colour blind? Option A 0% Option B 50% Option C 75% Option D 25%

Correct option: B Explanation: Autosomal recessive disorder present on X chromosome is known as color blindness. So, a man whose father was color blind who is normal (XY ) marries a female whose...

### Q 21. Select the correct matching of the type of joint with the example in human skeletal system: Type of Joint Example Option A Pivot joint Between third and fourth cervical vertebrae Option B Hinge joint Between humerus Option C Gliding joint Between carpals Option D Cartilaginous joint Between frontal and parietal

Correct Option: C Explanation: Much movement is not allowed by the gliding joint, only some gliding movements can be done. It is present between the carpals.

### Q 20. Tracheids differ from other tracheary elements in: Option A Being imperforate Option B Lacking nucleus Option C Being lignified Option D Having casparian strips

Correct Option: A Explanation: Tracheary elements consists of tracheids and vessels. They both take part in The transport of sap. Tracheids are different from other tracheary elements in being...

### Q 19. Which one of the following living organisms completely lacks a cell wall? Option A Sea-fan (Gorgonia) Option B Saccharomyces Option C Blue-green algae Option D Cyanobacteria

Correct Option: A Explanation: Sea-fan (Gorgonia), belonging to kingdom Animalia completely lacks the cell wall.

### Q 18. The solid linear cytoskeletal elements having a diameter of 6 nm and made up of a single type of monomer are known as Option A Microfilaments Option B Intermediate filaments Option C Lamins Option D Microtubules

Correct Option: A Explanation: The solid linear cytoskeletal elements having a diameter of 6 nm and made up of a single type of monomer are known as microfilaments.

### Q 17. Fructose is absorbed into the blood through mucosa cells of intestine by the process called: Option A Facilitated transport Option B Simple diffusion Option C Co-transport mechanism Option D Active transport

Correct Option: A Explanation: Facilitated transport is the process by which fructose is absorbed into the blood through mucosa cells of the intestine. Facilitated transport is the spontaneous...

### Q 16. Which is the particular type of drug that is obtained from the plant whose one flowering branch is shown below?Option A Depressant Option B Stimulant Option C Pain-killer Option D Hallucinogen

Correct option: D Explanation: The image represents the flowering branch of the plant Datura containing hallucinogens, which are normally used as medicines. It helps the patients to overcome with...

### Q 15. Select the option which is not correct with respect to enzyme action: Option A Addition of a lot of succinate does not reverse the inhibition of succinic dehydrogenase by malonate. Option B A non-competitive inhibitor binds the enzyme at a site distinct from that which binds the substrate. Option C Malonate is a competitive inhibitor of succinic dehydrogenase. Option D Substrate binds with the enzyme at its active site.

Correct option: A Explanation: competitive inhibitor of succinic dehydrogenase is malonate. Malonate competes with the substrate for the substrate-binding site of the enzyme. Similarly, the...

### Q 14. Which structures perform the function of mitochondria in bacteria? Option A Ribosomes Option B Cell wall Option C Mesosomes Option D Nucleoid

Correct Option: C Explanation: In bacteria, the function of the mitochondria is carried out by mesosomes. They are formed by the extensions of the plasma membrane into the cell.

### Q 13. Which of the following causes an increase in sodium reabsorption in the distal convoluted tubule? Option A Increase in antidiuretic hormone levels Option B Decrease in aldosterone levels Option C Decrease in antidiuretic hormone levels Option D Increase in aldosterone levels

Correct Option: D Explanation: When there is an increase in the aldosterone level it results in an increase in the reabsorption of the sodium in the distal convoluted tubule. This leads to an...

### Q 12. An example of edible underground stem is Option A Groundnut Option B Sweet potato Option C Potato Option D Carrot

Correct Option: C Explanation: Underground stem which is edible is of potato, and it stores food.

### Q 11. Identify the hormone with its correct matching of source and function. Option A Melatonin – Pineal gland – regulates the normal rhythm of sleep-wake cycle. Option B Progesterone – corpus luteum – secondary sex organs. Option C Atrial natriuretic factor –ventricular wall – increases the blood pressure. Option D Oxytocin – posterior pituitary – growth and maintenance of mammary glands.

Correct option: A Explanation: Melatonin hormone is secreted by the pineal gland, whose function is to regulate the normal rhythm of the sleep-wake cycle.

### Q 10. Fruit colour in squash is an example of: Option A Dominant epistasis Option B Complementary genes Option C Inhibitory genes Option D Recessive epistasis

Correct Option: A Explanation: Fruit color in squash is an example of dominant epistasis. In this, the dominant gene masks the effect of the recessive gene and gives it a white color appearance.

### Q 9. A species facing extremely high risk of extinction in the immediate future is called: Option A Endemic Option B Critically endangered Option C Extinct Option D Vulnerable

Correct Option: B Explanation: Critically endangered species are those species which are facing extremely high risk of extinction in the immediate future.

### Q 8. In ‘S’ phase of the cell cycle: Option A The amount of DNA remains same in each cell Option B The chromosome number is increased. Option C The amount of DNA is reduced to half in each cell. Option D The amount of DNA doubles in each cell.

Correct option: D Explanation: Synthesis or S phase is the period when the DNA doubles in the amount in each and every cell, that is replication of DNA takes place.

### Q 7. You are given a fairly old piece of dicot stem and a dicot root. Which of the following anatomical structures will you use to distinguish between the two? Option A Secondary phloem Option B Protoxylem Option C Cortical cells Option D Secondary xylem

Correct option: B Explanation: The position of the protoxylem in the stem is towards the center, while the metaxylem lies towards the periphery of the organ. This is known as endarch. While it is...

### Q 6. Just as a person moving from Delhi to Shimla to escape the heat for the duration of hot summer, thousands of migratory birds from Siberia and other extremely cold northern regions move to: Option A Meghalaya Option B Corbett National Park Option C Keoladeo National Park Option D Western Ghat

Correct option: C Explanation: thousands of migratory birds from Siberia and other extremely cold northern regions move to Keoladeo National Park, located in Bharatpur Rajasthan. Presently it is...

### Q 4. Choose the correctly matched pair: Option A Moist surface of buccal cavity – Glandular epithelium Option B Tubular parts of nephrons – Cuboidal epithelium Option C Inner surface of bronchioles – Squamous epithelium Option D Inner lining of salivary ducts – Ciliated epithelium

Correct option: B Explanation: Single layer of cube cells make up the cuboidal epithelium. It is present in the tubular part of the nephron in the kidneys. Its main functions are absorption and...

### Q 3. In which one of the following processes CO2 is not released? Option A Aerobic respiration in animals Option B Alcoholic fermentation Option C Lactate fermentation Option D Aerobic respiration in plants

Correct option: C Explanation: In lactate fermentation, carbon dioxide is not released. While aerobic respiration taking place in animals and plants, and in the fermentation of alcohol carbon...

### Q 2. The main function of mammalian corpus luteum is to produce: Option A Progesterone Option B Human chorionic gonadotropin Option C Relaxin only Option D Estrogen only

Correct option: A Explanation: The main function of the corpus luteum is to secrete progesterone, which is required for maintenance of the endometrium.

### Q 1. Five kingdom system of classification suggested by R.H. Whittaker is not based on Option A Mode of reproduction Option B Mode of nutrition Option C Complexity of body organization Option D Habitat

Correct option: D Explanation: R.H. Whittaker suggested the five-kingdom classification. This classification is based on cell structure, mode of nutrition, organization of thallus, reproduction, and...

### A series LCR circuit containing 5.0 H inductor, 80 micro F capacitor and 40 ohms resistor is connected to 230 V variable frequency ac source. The angular frequencies of the source at which power transferred to the circuit is half the power at the resonant angular frequency are likely to be

(1) 25 rad/s and 75 rad/s (2) 50 rad/s and 25 rad/s (3) 46 rad/s and 54 rad/s (4) 42 rad/s and 58 rad/s Solution: Answer (3)

### From a circular ring of mass ‘M’ and radius ‘R’ an arc corresponding to a 90° sector is removed. The moment of inertia of the remaining part of the ring about an axis passing through the centre of the ring and perpendicular to the plane of the ring is ‘K’ times ‘MR2’. Then the value of ‘K’ is

(1) 3/4 (2) 7/8 (3) 1/4 (4) 1/8 Solution; Answer (1) M(remain) = 3/4M I = Mremain R2 I = ¾ MR2 So, the correct option is 3/4

### Two conducting circular loops of radii R1 and R2 are placed in the same plane with their centres coinciding. If R1 > > R2, the mutual inductance M between them will be directly proportional to

(a) R1/R2 (b) R2/R1 (c) R12/R2 (d) R22/R1 Solution: Answer (4) The magnetic field at the centre of the primary coil is given by: $B=\frac{{{\mu }_{0}}I}{2{{R}_{1}}}$ Considering it to be uniform,...

### A uniform conducting wire of length 12a and resistance ‘R’ is wound up as a current carrying coil in the shape of, (i) an equilateral triangle of side ‘a’. (ii) a square of side ‘a’. The magnetic dipole moments of the coil in each case respectively are

(1) √3Ia2 and 3Ia2 (2) 3 Ia2 and Ia2 (3) 3 Ia2 and Ia2 (4) 4 Ia2 and 3 Ia2 Solution: Answer (1) Current in the loop will be I=V/R which is the same for both loops. Now the magnetic moment of...

### A uniform rod of length 200 cm and mass 500 g is balanced on a wedge placed at 40 cm mark. A mass of 2 kg is suspended from the rod at 20 cm and another unknown mass ‘m’ is suspended from the rod at 160 cm mark as shown in the figure. Find the value of ‘m’ such that the rod is in equilibrium. (g = 10 m/s2)

(1) 1/2kg (2) 1/3kg (3) 1/6kg (4) 1/12kg Solution: Answer (4) By balancing torque, 2g x 20 = 0.5g x 60 + mg x 120 m = 0.5/6 kg = 1/12kg

### For the given circuit, the input digital signals are applied at the terminals A, B and C. What would be the output at the terminal y?

Solution: Answer (3)

### In the product

$ \vec{F}=q(\vec{v}\times \vec{B}) $ $ \vec{F}=q\vec{v}(B\hat{i}+B\hat{j}+{{B}_{0}}\hat{k}) $ $ For\,q=1\,and\,\vec{v}=2\hat{i}+4\hat{j}+6\hat{k}\,and\, $ $ \vec{F}=4\hat{i}-20\hat{j}+12\hat{k} $ $...

### Twenty seven drops of same size are charged at 200 V each. They combine to form a bigger drop. Calculate the potential of the bigger drop.

(1) 660 V (2) 1320 V (3) 1520 V (4) 1980 V Solution: Answer (4)

### A point object is placed at a distance of 60 cm from a convex lens of focal length 30 cm. If a plane mirror were put perpendicular to the principal axis of the lens and at a distance of 40 cm from it, the final image would be formed at a distance of 60 cm 40 cm

(1) 20 cm from the lens, it would be a real image (2) 30 cm from the lens, it would be a real image (3) 30 cm from the plane mirror, it would be a virtual image (4) 20 cm from the plane mirror, it...

### A car starts from rest and accelerates at 5 m/s2. At t = 4 s, a ball is dropped out of a window by a person sitting in the car. What is the velocity and acceleration of the ball at t = 6 s?

(1) 20 m/s, 5 m/s2 (2) 20 m/s, 0 (3) 20 2 m/s, 0 (4) 20 2 m/s, 10 m/s2 Solution: Answer (4) Initial velocity of car = 0 Acceleration of car = 5 m/s2 Velocity of car at t = 4 s; v = u + at Therefore,...

### A particle of mass ‘m’ is projected with a velocity v = kVe (k < 1) from the surface of the earth. (Ve = escape velocity) The maximum height above the surface reached by the particle is

Solution: Answer (4)\ given v = kVe where, k < 1 Thus, v < Ve From conservation of mechanical energy

### A particle moving in a circle of radius R with a uniform speed takes a time T to complete one revolution. If this particle were projected with the same speed at an angle ‘’ to the horizontal, the maximum height attained by it equals 4R. The angle of projection, , is then given by :

Solution; Answer (4) T = 2πR/v ⇒ v = 2πR/T

### A ball of mass 0.15 kg is dropped from a height 10 m, strikes the ground and rebounds to the same height. The magnitude of impulse imparted to the ball is

(g = 10 m/s2) nearly (1) 0 kg m/s (2) 4.2 kg m/s (3) 2.1 kg m/s (4) 1.4 kg m/s Solution; Answer (2) According to the question, the mass of the ball =...

### A step down transformer connected to an ac mains supply of 220 V is made to operate at 11 V, 44 W lamp. Ignoring power losses in the transformer, what is the current in the primary circuit?

(1) 0.2 A (2) 0.4 A (3) 2 A (4) 4 A Solution: Answer (1) In ideal transformer, we know that: Input power = Output power 220 ×...

### If force [F], acceleration [A] and time [T] are chosen as the fundamental physical quantities. Find the dimensions of energy.

(1) [F][A][T] (2) [F][A][T2] (3) [F][A][T–1] (4) [F][A–1][T] Solution: Answer (2) We know that, [E] = [Fa][Ab][Tc] => [ML2T–2] = [MLT–2]a [LT–2]b...

### A convex lens ‘A’ of focal length 20 cm and a concave lens ‘B’ of focal length 5 cm are kept along the same axis with a distance ‘d’ between them. If a parallel beam of light falling on ‘A’ leaves ‘B’ as a parallel beam, then the distance ‘d’ in cm will be

(1) 25 (2) 15 (3) 50 (4) 30 Solution: Answer (2) After refraction by a convex lens, parallel beams of light...

### If E and G respectively denote energy and gravitational constant, then E/G has the dimensions o

(1) [M2] [L–1] [T0] (2) [M] [L–1] [T–1] (3) [M] [L0] [T0] (4) [M2] [L–2] [T–1] Solution: Answer (1) Dimensional formula of energy [E] = [M1 L2 T–2] ...(I) Dimensional formula of gravitational...

### A capacitor of capacitance ′C′, is connected across an ac source of voltage V, given by V=V0sinωtV The displacement current between the plates of the capacitor, would then be given by:

$ (1)\,\,{{I}_{d}}={{V}_{0}}\omega C\cos \omega t $ $ (2)\,\,{{I}_{d}}=\frac{{{V}_{0}}}{\omega C}\cos \omega t $ $ (3)\,\,{{I}_{d}}=\frac{{{V}_{0}}}{\omega C}\sin \omega t $ $...

### A solid cylinder of mass 2 kg and radius rolls up an inclined plane of angle of inclination . The centre of mass of the cylinder has speed of . The distance travelled by the cylinder on the inclined surface will be, [take ] (1) (2) (3) (4)

Answer (1) SoI. As $v=\sqrt{\frac{2 g h}{1+\frac{K^{2}}{\mathbf{R}^{2}}}}$ $v^{2}=\frac{2 g h}{1+\frac{1}{2}} \quad\left[\frac{K^{2}}{R^{2}}=\frac{1}{2}\right.$ for solid cylinder $]$ $...

### An object of mass , initially at rest, is acted upon by a variable force whose X-component varies with in the manner shown. The velocities of the object at the points and , would have the respective values of (nearly) (1) and (2) and (3) and (4) and

Answer (4) Sol. Using work-energy theorem $\Delta K=$ work $=$ area under $F=x$ graph From $x=0$ to $x=8 m$ $ \begin{array}{l} \frac{1}{2} m v^{2}=100+30 \\ v^{2}=520 \\ v=\sqrt{520}=23 \mathrm{~m}...

### A particle of mass at rest suddenly breaks on its own into three fragments. Two fragments of mass each move along mutually perpendicular direction with speed v each. The energy released during the process is, (1) (2) (3) (4)

Answer (1) Sol. From conservation of linear momentum. $0=m v \hat{j}+m v \hat{i}+3 m v_{1}$ $\vec{v}_{1}=-\frac{v}{3}(\hat{i}+\hat{j})$ $v_{1}=\frac{\sqrt{2}}{3} v$ $K E_{i}=0$ $K E_{f}=\frac{1}{2}...

### A body of mass is kept on a rough horizontal surface (coefficient of friction ). A horizontal force is applied on the body, but it does not move. The resultant of normal reaction and the frictional force acting on the object is given by F, where is, (1) (2) (3) (4)

Answer (4) Sol. Since body does not move hence it is in equilibrium. $\mathrm{f}_{\mathrm{r}}=$ frictional force which is less than or equal to limiting friction. Now $\mathrm{N}=\mathrm{mg}$ Hence...

### The stress-strain curves are drawn for two different materials and . It is observed that the ultimate strength point and the fracture point are close to each other for material but are far apart for material . We can say that materials and are likely to be (respectively), (1) Plastic and ductile (2) Ductile and brittle (3) Brittle and ductile (4) Brittle and plastic

Answer (3) Sol. As given that fracture point and ultimate strength point is close for material $\mathrm{X}$, So, $\mathrm{X}$ is brittle in nature and both points are far apart for material $Y$...

### Consider the following statements (A) and (B) and identify the correct answer. (A) A zener diode is connected in reverse bias, when used as a voltage regulator. (B) The potential barrier of p-n junction lies between 0.1 V to 0.3 V.

(1) (A) and (B) both are correct. (2) (A) and (B) both are incorrect (3) (A) is correct and (B) is incorrect. (4) (A) is incorrect but (B) is correct. Solution: Answer (3) When reverse biassed, the...

### Two bullets are fired horizontally and simultaneously towards each other from roof tops of two buildings apart and of same height of , with the same velocity of . When and where will the two bullets collide? (1) They will not collide (2) After at a height of (3) After at a height of (4) After at a height of

Answer (2) Sol. Let bullets collide at time t $ \begin{array}{l} x_{1}+x_{2}=100 \mathrm{~m} \\ 25 t+25 t=100 \\ t=2 s \\ \begin{array}{r} y=\frac{1}{2} g t^{2}=\frac{1}{2} \times 10 \times 2^{2} \\...

### A double convex lens has focal length . The radius of curvature of one of the surfaces is double of the other. Find the radii if the refractive index of the material of the lens is 1.5. (1) (2) (3) (4)

Answer (4) Sol. Focal length of lens is $\frac{1}{f}=(\mu-1)\left(\frac{1}{R_{1}}-\frac{1}{R_{2}}\right)$, $ \begin{array}{l} \frac{1}{25}=(1.5-1)\left(\frac{1}{R}+\frac{1}{2 R}\right) \\...

### A radioactive nucleus Z undergoes spontaneous decay in the sequence in following manner where Z is the atomic number of element X. The possible decay particles in the sequence are

Solution : Answer 3 β+ decreases the atomic number by 1, α decreases the atomic number by 2, and the β- decreases the atomic number by 1. Hence the correct order is given by the option 3

### In a Young’s double slit experiment, if there is no initial phase difference between the light from the two slits, a point on the screen corresponding to the fifth minimum has path difference (1) (2) (3) (4)

Answer (4) Sol. Path difference for destructive interference in YDSE $ \begin{array}{c} \Rightarrow \Delta X_{n}=\frac{(2 n-1)}{2} \lambda \quad n=1,2,3 \ldots . \\ \Delta X_{5^{k+}}=\left(\frac{2...

### An equiconvex lens has power . It is cut into two symmetrical halves by a plane containing the principal axis. The power of one part will be, (1) (2) 0 (3) (4)

Answer (1) When a lens is cut in half as illustrated in the diagram, the power of each half is the same. i.e. P, because the focal length is the same.

### Two identical capacitors and of equal capacitance are connected as shown in the circuit. Terminals a and of the key are connected to charge capacitor using battery of emf V volt. Now disconnecting a and the terminals and are connected. Due to this, what will be the percentage loss of energy? (1) (2) (3) (4)

Answer (4) $\mathrm{Sol}$, Switch the key at point $c$ $ \begin{array}{l} \frac{q_{0}-q}{C}=\frac{q}{C} \\ 2 q=q_{0} \\ q=\left(\frac{q_{0}}{2}\right) \\...

### A sphere encloses an electric dipole with charges C. What is the total electric flux across the sphere? (1) (2) (3) Zero (4)

Answer (3) Sol. $\phi_{\text {Total }}=\frac{\mathbf{q}_{\text {enclosed }}}{\varepsilon_{0}}$ Because dipoles have equal and opposing charges, there will be no net charge inside the sphere....

### Polar molecules are the molecules

(1) Having zero dipole moment (2) Acquire a dipole moment only in the presence of electric field due to displacement of charges (3) Acquire a dipole moment only when magnetic field is absent (4)...

### For a transparent medium, relative permeability and permittivity, and are and respectively. The velocity of light in this medium would be, (1) (2) (3) (4)

Answer (2) Sol. $v=\frac{1}{\sqrt{\mu \in}}=\frac{\mathbf{c}}{\sqrt{\mu_{r} \in_{r}}}$ $ \begin{array}{l} =\frac{3 \times 10^{8}}{\sqrt{1 \times 1.44}} \\ =2.5 \times 10^{8} \mathrm{~m} / \mathrm{s}...

### A cycle wheel of radius is rotated with. constant angular velocity of 10 rad/s in a region of magnetic field of 0.1 T which is perpendicular to the plane of the wheel. The EMF generated between its centre and the rim is, (1) Zero (2) (3) (4)

Answer (3) Solution: $ \begin{array}{l} e=\frac{B 1^{2} \omega}{2} \\ =\frac{1}{2} \times 0.1 \times\left(\frac{1}{2}\right)^{2} \times 10 \\ =\frac{1}{8} \\ =0.125 \mathrm{~V} \end{array}...

### A parallel plate capacitor has a uniform electric field ‘ E ‘ in the space between the plates. If the distance between the plates is ‘d’ and the area of each plate is ‘A’, the energy stored in the capacitor is (Epsillon = permittivity of free space)

The capacitance of a parallel plate capacitor is $ C=\frac{{{\in }_{0}}A}{d} $ Potential difference between the plates is V = Ed ........ (ii) Then, the energy stored in the capacitor is given...

### A circuit when connected to an AC source of gives a current of . The same circuit when connected to a DC source of , gives a current of . The circuit is (1) Series LCR (2) Series LR (3) Series RC (4) Series LC

Answer (2) Sol. $I_{1}=\frac{V}{Z}$ $ I_{1}=\frac{12}{\sqrt{R^{2}+\left(X_{I}-X_{c}\right)^{2}}}=0.2 \mathrm{~A} $ In the second situation, the capacitor would give infinite resistance, but since...

### The time period of a geostationary satellite is , at a height is radius of earth) from surface of earth. The time period of another satellite whose height is from surface will be, (1) (2) (3) (4)

Answer (2) Sol. $T^{2} \propto r^{3}$ $\mathbf{T}^{2} \propto\left(\mathbf{R}_{\mathrm{E}}+\mathbf{h}\right)^{3}$...

### The rate of radioactive disintegration at an instant for a radioactive sample of half life is . The number of radioactive atoms in that sample at that instant is, (1) (2) (3) (4)

Answer (1) Sol. $T_{1 / 2}=\frac{\ln 2}{\lambda}=\frac{0.693}{\lambda}$ $ \begin{array}{l} 2.2 \times 10^{9}=\frac{0.693}{\lambda} \\ \lambda=\frac{0.693}{2.2 \times 10^{9}}=3.15 \times 10^{-10} \\...

### An object flying in air with velocity suddenly breaks into two pieces whose masses are in the ratio . The smaller mass flies off with a velocity The velocity of the larger piece will be, (1) (2) (3) (4)

Answer (2) Sol. By conservation of linear momentum $\overline{\mathbf{P}}=\overrightarrow{\mathbf{P}}_{\mathrm{f}}$ $\mathrm{mv}_{1}=\left(\frac{\mathrm{m}}{6} \overline{\mathrm{v}}_{1}+\frac{5...

### A nucleus with mass number 240 breaks into two fragments each of mass number 120, the binding energy per nucleon of unfragmented nuclei is 7.6 MeV while that of fragments is 8.5 MeV. The total gain in the Binding Energy in the process is

(1) 0.9 MeV (2) 9.4 MeV (3) 804 MeV (4) 216 MeV Solution: Answer (4) Reactant mass number = 240 Reactant mass number = 240 The total number of products is 120. BE per product nucleon = 8.5 MeV Total...

### A tuning fork with frequency 800 Hz produces resonance in a resonance column tube with upper end open and lower end closed by water surface. Successive resonance are observed at lengths and . The speed of sound in air is, (1) (2) (3) (4)

Answer (4) $ \begin{array}{l} I_{1}=9.75 \mathrm{~cm} \\ I_{2}=31.25 \mathrm{~cm} \\ I_{3}=52.75 \mathrm{~cm} \\ e=\text { end correction } \end{array} $ $ \frac{3 \lambda}{4}+e=31.25 \mathrm{~cm} $...

### A mass falls from a height ‘ ‘ and its time of fall ‘t’ is recorded in terms of time period of a simple pendulum. On the surface of earth it is found that . The entire set up is taken on the surface of another planet whose mass is half of that of earth and radius the same. Same experiment is repeated and corresponding times noted as ‘ and ‘ . Then we can say (1) (2) (3) (4)

Answer (1) Sol. For surface of earth time taken in falling $\mathrm{h}$ distance. $ \begin{array}{l} t=\sqrt{\frac{2 h}{g}} \\ \text { and } \quad T=2 \pi \sqrt{\frac{1}{g}} \end{array} $ Given...

### A body is executing simple harmonic motion with frequency ‘n’, the frequency of its potential energy is

(1) n (2) 2n (3) 3n (4) 4n Solution: Answer (2) Displacement equation of SHM of frequency 'n' is: x = Asin(ωt) = Asin(2πnt) So the frequency of potential energy = 2n

### The distance covered by a particle undergoing SHM in one time period is amplitude , (1) (2) Zero (3) (4)

Answer (1) Sol. The total distance travelled by the particle in one time period is $4 \mathrm{~A}$.

### Two metal spheres, one of radius and the other of radius respectively have the same surface charge density They are brought in contact and separated. What will be the new surface charge densities on them? (1) (2) (3) (4)

Answer (1) Sol. $Q_{1}=\sigma 4 \pi R_{1}{ }^{2}=\sigma 4 \pi R^{2}$ $ \mathbf{Q}_{2}=\sigma 4 \pi(2 R)^{2}=\sigma 16 \pi R^{2} $ After Redistribution of charges $ \begin{array}{l}...

### The variation of EMF with time for four types of generators are shown in the figures. Which amongst them can be called AC?(1) Only (a) (2) (a) and (d) (3) (4) and .

Answer (3) Alternating current is a type of current that alternates its direction on a regular basis. As a result, all of the options involve AC

### A straight conductor carrying current i splits into two parts as shown in the figure. The radius of the circular loop is R. The total magnetic field at the centre P of the loop is, (1) , inward (2) Zero (3) , outward (4) , inward

Answer (2) Solution: Net magnetic field at point 'P' $ \mathbf{B}_{\text {net }}=\overrightarrow{\mathbf{B}_{1}}+\overline{\mathbf{B}_{2}} $ Here $\bar{B}_{1}$ and $\bar{B}_{2}$ are equal in...

### Two toroids 1 and 2 have total no. of turns 200 and 100 respectively with average radii and respectively. If they carry same current i, the ratio of the magnetic fields along the two loops is, (1) (2) (3)

Answer (2) Sol. Magnetic field inside a toroid in $ \mathrm{B}=\frac{\mu_{0} \mathrm{~N} \cdot \mathbf{I}}{2 \pi \mathrm{R}} $ Here,...

### A truck is stationary and has a bob suspended by a light string, in a frame attached to the truck. The truck suddenly moves to the right with an acceleration of a. The pendulum will tilt (1) to the left and angle of inclination of the pendulum with the vertical is (2) to the left and angle of inclination of the pendulum with the vertical is (3) to the left and angle of inclination of tha pendulum with the vertical is (4) to the left and angle of inclination of the pendulum with the vertical is

Answer (3) Sol. From the frame of truck $ \begin{array}{l} \operatorname{Tsin} \theta=\mathbf{m a} \\ T \cos \theta=\mathrm{mg} \end{array} $ $\theta=\tan...

### A person standing on drops a coin. The coin reaches the floor in time if the elevator is at rest and in time if the elevator is moving uniformly. Then (1) (2) or depending upon whether the lift is going up or down (3) (4)

Answer (1) Sol. Because the elevator is an inertial frame of reference in both cases, the effective gravity is the same in both cases. So, time of fall remains same in both cases (since initial...

### A particle starting from rest, moves in a circle of radius ‘ It attains a velocity of in the round. Its angular acceleration will be, (1) (2) (3) (4)

Answer (4) Sol. Initial speed $=0$ Final speed = Tangential acceleration=$\alpha r$ $V^{2}=u^{2}+2 a s$ $V_{0}^{2}=0+2 r \alpha(2 \pi r) n$ $\alpha=\frac{V_{0}^{2}}{4 \pi n r^{2}}$

### Two small spherical metal balls, having equal masses, are made from materials of densities and and have radii of and , respectively, they are made to fall vertically (from rest) in a viscous medium whose coefficient of viscosity equals and whose density is The ratio of their terminal velocities would be, (1) (2) (3) (4)

Answer (1) Solution: As $V_{T}=\frac{2 a^{2}}{9 \eta}(\rho-\sigma) g$ $ \begin{array}{l} V_{T_{1}}=\frac{2 \times(1)^{2}}{9 \eta}\left(\rho_{1}-0.1 \rho_{2}\right) g \\ V_{T_{1}}=\frac{2 \times 1}{9...

### An object kept in a large room having air temperature of takes 12 minutes to cool from to . The time taken to cool for the same object from to would be nearly, (1) (2) (3) (4)

Answer (1) Sol. On using Newton's law of cooling $ \begin{array}{l}...

### A proton and an particle are accelerated from rest to the same energy. The de Broglie wavelengths and are in the ratio, (1) (2) (3) (4)

Answer (2) Sol. As $\lambda=\frac{h}{\rho}=\frac{h}{\sqrt{2 m K . E}}$ $\therefore \lambda \propto \frac{1}{\sqrt{m}}$ (Kinetic energies are same) $ \begin{array}{l}...

### The velocity of a small ball of mass M and density d, when dropped in a container filled with glycerine becomes constant after some time. If the density of glycerine is 2 d , then the viscous force acting on the ball will be

(1) 2Mg (2) Mg (3) 3Mg/2 (4) 2Mg Solution: Answer (1) According to the question, Mass = M The density of ball = d The density of glycerine = d/2 Then, we have:

### The work function of a photosensitive material is . The longest wavelength of light that can cause photon emission from the substance is (approximately) (1) (2) (3) (4)

Answer (1) Sol. As $E=\frac{12400}{\lambda}(E$ is in $\mathrm{eV}$ and $\lambda$ is in $\AA$ ) $ \begin{array}{l} \lambda=\frac{12400}{4} \\ =3100 \mathrm{~A} \\ \therefore \quad \lambda=310...

### Angular width of the central maxima in the Fraunhofer diffraction for is When the same slit is illuminated by another monochromatic light, the angular width decreases by . The wavelength of this light is (1) (2) (3) (4)

Answer (3) Sol. As $\theta=\frac{2 \lambda}{a}$ $ \begin{array}{l} \theta_{0}=\frac{2 \times 6000}{\mathbf{a}} \\ \frac{\theta^{\prime}}{\theta_{0}}=\frac{\lambda^{\prime}}{6000} \\ \Rightarrow...

### of water, of volume at , is converted into steam at same temperature under normal atmospheric pressure . The volume of steam formed equals . If the specific latent heat of vaporisation of water is , the change in internal energy is, (1) (2) (3) (4)

Answer (3) Sol. $ \begin{aligned} \Delta Q &=2256 \times 1=2256 \mathrm{~J} \\ \Delta \mathrm{W} &=P\left[V_{\text {steam }}-V_{\text {water }}\right] \\ &=1 \times 10^{5}[1671-1] \times...

### A spring is stretched by 5 cm by a force 10 N. The time period of the oscillations when a mass of 2 kg is suspended by it is

(1) 0.0628 s (2) 6.28 s (3) 3.14 s (4) 0.628 s Solution: Answer (4) F = kx 10 = k(5 × 10–2) k = 10/5 × 10 – 2 k = 2 x 102 k = 200 N/m $...

### Assuming that the gravitational potential energy of an object at infinity is zero, the change in potential energy (final – initial) of an object of mass , when taken to a height from the surface of earth (of radius ), is given by, (1) (2) (3) (4) .

Answer (3) $(\mathrm{P} . \mathrm{E})_{\mathrm{A}}=-\frac{\mathrm{GMm}}{\mathrm{R}}$ $(P . E)_{B}=-\frac{G M m}{R+h}$ $\therefore \Delta U=(P . E)_{B}-(P . E)_{A}$ $=-\frac{G M m}{R+h}+\frac{G M...

### A person travelling in a straight line moves with a constant velocity for certain distance and with a constant velocity for next equal distance. The average velocity is given by the relation (1) (2) (3) (4)

Answer (3) Sol. As $t_{1}=\frac{x}{v_{1}}$ and $t_{2}=\frac{x}{v_{2}}$ $ \begin{array}{l} \therefore \quad v=\frac{x+x}{t_{1}+t_{2}} \\ \qquad=\frac{2 x}{\frac{x}{v_{1}}+\frac{x}{v_{2}}}=\frac{2...

### The main scale of a vernier callipers has divisions/cm. divisions of the vernier scale coincide with divisions of main scale. The least count of the vernier callipers is, (1) (2) (3) (4)

Answer (4) Sol. $n V S D=(n-1)$ MSD $1 \mathrm{VSD}=\frac{(\mathrm{n}-1)}{\mathrm{n}} \mathrm{MSD}$ $ \begin{aligned} \text { L.C. } &=1 \mathrm{MSD}-1 \mathrm{VSD} \\ &=1...

### The value of , for hydrogen, helium and another ideal diatomic gas (whose molecules are not rigid but have an additional vibrational mode), are respectively equal to, (1) (2) (3) (4)

Answer (2) Sol. If the vibrational mode is ignored, diatomic gases have 5 degrees of freedom. When the vibrational mode is taken into account, the degrees of freedom of diatomic gas molecules...

### The circuit diagram shown here corresponds to the logic gate,

1. NAND

2.NOR

3.AND

4.OR

Answer (2) Explanation: Case 1: If A = 0 and B = 0 are both true, the LED will light up. If Y = 1 is true, the LED will light up. Case 2: A = 0 and B = 1. LED Y = 0 will not have any current flowing...

### Match Column – I and Column – II and choose the correct match from the given choices.

(1) (A) - (R), (B) - (P), (C) - (S), (D) - (Q) (2) (A) - (Q), (B) - (R), (C) - (S), (D) - (P) (3) (A) - (Q), (B) - (P), (C) - (S), (D) - (R) (4) (A) - (R), (B) - (Q), (C) - (P), (D) - (S) Solution:...

### An LED is constructed from a p-n junction diode using GaAsP. The energy gap is . The wavelength of the light emitted will be equal to (1) (2) (3) (4)

Answer (3) Sol. Wavelength of light emitted. $ \begin{aligned} \lambda &=\frac{12400}{E_{g}(\text { in } e V)} \bar{A} \\ &=\frac{12400}{1.9}=6526 \mathrm{~A} \\ &=653 \mathrm{~nm} \\...

### A deep rectangular pond of surface area , containing water (density ), specific heat capacity ), is located in a region where the outside air temperature is at a steady value of . The thickness of the frozen ice layer in this pond, at a certain instant is . Taking the thermal conductivity of ice as , and its specific latent heat of fusion as , the rate of increase of the thickness of ice layer, at this instant, would be given by (1) (2) (3) (4)

Answer (4) Sol. Assume at any instant thickness of ice is $\mathrm{x}$. And time taken to form additional thickness. $(\mathrm{dx})$ is $\mathrm{dt}$. $\mathrm{mL}=\frac{\mathrm{KA}[26-0] \mathrm{d}...

### The electron concentration in an n-type a semiconductor is the same as hole concentration in a p-type semiconductor. An external field (electric) is applied across each of them. Compare the currents in them.

(1) Current in n-type = current in p-type (2) Current in p-type > current in n-type (3) Current in n-type > current in p-type (4) No current will flow in p-type, current will only flow in...

### In a u-tube as shown in the fig. water and oil are in the left side and right side of the tube respectively. The heights from the bottom for water and oil columns are and respectively. The density of the oil is [take (1) (2) (3) (4)

Answer (3) Sol. In equilibrium Pressure at $A=$ Pressure at $B$. $ P_{a}+0.15 \times 10^{3} \times g=P_{a}+0.20 \times d_{0} g $ $ \begin{aligned} d_{0} &=\frac{0.15 \times 10^{3}}{0.20}...

### The relations amongst the three elements of earth’s magnetic field, namely horizontal component , vertical component and are, total magnetic field) (1) (2) tan\delta, (3) (4)

Answer (3) Sol. $H=B_{E} \cos \delta_{1}$ $ \mathrm{V}=\mathbf{B}_{\mathrm{E}} \sin \delta^{\mathrm{i}} $

### Water falls from a height of 60 m at the rate of 15 kg/s to operate a turbine. The losses due to frictional force are 10% of the input energy. How much power is generated by the turbine? (g = 10 m/s2)

(1) 10.2 kW (2) 8.1 kW (3) 12.3 kW (4) 7.0 kW Solution; Answer (2) Incident power on turbine is given by d(mgh)/dt = (gh) dm/dt = 10 × 60 × 15 =...

### The metre bridge shown is in balance position with . If we now interchange the positions of galvanometer and cell, will the bridge work? If yes, what will be balance condition? (1) yes, (2) yes, (3) no, no null point yes,

Answer (1) Sol. In balanced bridge (initially) In balanced bridge (finally) $ \begin{array}{l} \frac{P}{L_{1}}=\frac{Q}{l_{2}} \\ \frac{P}{Q}=\frac{L_{1}}{l_{2}} \end{array} $ The equilibrium state...

### In a potentiometer circuit a cell of EMF 1.5 V gives balance point at 36 cm length of wire. If another cell of EMF 2.5 V replaces the first cell, then at what length of the wire, the balance point occurs?

(1) 60 cm (2) 21.6 cm (3) 64 cm (4) 62 cm Solution: Answer (1) From the application of potentiometer to compare two...

### The reading of an ideal voltmeter in the circuit shown is, (1) (2) (3) (4)

Answer (1) Sol. Current in $\mathrm{APB}=\frac{2}{50} \mathrm{~A}$ Current in $A Q B=\frac{2}{50} A$ $\Delta V$ from $A$ to $P$ $ \mathrm{V}_{\mathrm{A}}-\frac{2}{50} \times...

### The radius of the first permitted Bohr orbit, for the electron, in a hydrogen atom equals and its ground state energy equals . If the electron in the hydrogen atom is replaced by muon [charge same as electron and mass , the first Bohr radius and ground state energy will be, (1) (2) (3) (4)

The correct answer is (4) Sol. $r_{n} \propto \frac{1}{m}$ $ \begin{array}{l} \mathrm{r}_{\mu}=\frac{0.51}{207}=2.56 \times 10^{-13} \mathrm{~m} \\ \mathrm{E} \propto \mathrm{m}_{\mathrm{e}} \\...

### The half-life of a radioactive nuclide is 100 hours. The fraction of original activity that will remain after 150 hours would be

$ (1)\,\frac{1}{2} $ $ (2)\,\frac{1}{2\sqrt{2}} $ $ (3)\,\frac{2}{3} $ $ (4)\,\frac{2}{3\sqrt{2}} $ Solution: Answer (2) The activity of a radioactive substance is given as follows:

### The escape velocity from the Earth’s surface is v. The escape velocity from the surface of another planet having a radius, four times that of Earth and same mass density is

(1) v (2) 2v (3) 3v (4) 4v Solution: Answer (4) Escape velocity from the Earth's surface is given...

### A small block slides down on a smooth inclined plane, starting from rest at time t = 0. Let Sn be the distance travelled by the block in the interval t = n – 1 to t = n. Then, the ratio Sn/Sn+1 is given by:

$ (1)\,\,\frac{2n-1}{2n} $ $ (2)\,\,\frac{2n-1}{2n+1} $ $ (3)\,\,\frac{2n+1}{2n-1} $ $ (4)\,\,\frac{2n}{2n-1} $ Solution: Answer (2) Suppose theta is the inclination of inclined plane Therefore,...

### Find the value of the angle of emergence from the prism. Refractive index of the glass is 1.732.

(1) 60° (2) 30° (3) 45° (4) 90° Solution: Answer (1) From the ray diagram shown in the figure, we can say that r1 + r2 = A = 30° r2...

### The effective resistance of a parallel connection that consists of four wires of equal length, equal area of cross-section and same material is 0.25 ohms. What will be the effective resistance if they are connected in series?

(1) 0.25 ohms (2) 0.5 ohms (3) 1 ohms (4) 4 ohms Solution: Answer (4) Because all of the wires are identical and made of the same material, they...

### The equivalent capacitance of the combination shown in the figure is

(1) 3C (2) 2C (3) C/2 (4) 3C/2 Solution: Answer (2)

### A beam of light consisting of red, green and blue colours is incident on a right angled prism. The refractive index of the material of the prism for the above red, green and blue wavelengths are and respectively. The prism will: (1) Separate the red colour part from the green and blue colours (2) Separate the blue colour part from the red and green colours (3) Separate all the three colours from one another. (4) Not separate the three colours at all

Solution: (1) For $\mathrm{TIR} I>\mathrm{I}_{\mathrm{c}}$ so $\operatorname{Sin} \mathrm{i}>\sin \mathrm{I}_{\mathrm{c}}$ $ \operatorname{Sin} 45^{\circ}>\frac{1}{\mu} \Rightarrow \mu...

### A photoelectric surface is illuminated successively by monochromatic light of wavelength and . If the maximum kinetic energy of the emitted photoelectrons in the second case is 3 times that in the first case, the work function of the surface of the material is: (h Planck’s constant, speed of light) (1) (2) (3) (4)

Solution: (2) $ \begin{array}{l} k_{1}=\frac{h c}{\lambda}-\psi \\ k_{2}=3 k_{1}=\frac{2 h c}{\lambda}-\psi=\frac{3 h c}{\lambda}-3 \psi \end{array} $ So $2 \psi=\frac{h c}{\lambda}$ So...

### The value of coefficient of volume expansion of glycerin is . The fractional change in the density of glycerin for a rise of in its temperature is: (1) (2) (3) (4)

Solution: (3) $ \begin{array}{l} \rho=\rho_{0}(1-\gamma \Delta t) \\ \frac{\Delta \rho}{\rho_{0}}=\gamma \Delta T=\left(5 \times 10^{-4}\right)(40)=0.02 \end{array} $

### A cup of coffee cools from 90°C to 80°C in t minutes, when the room temperature is 20°C. The time taken by a similar cup of coffee to cool from 80°C to 60°C at a room temperature same at 20°C is

(1) 13t/10 (2) 13t/5 (3) 10t/13 (4) 5t/13 Solution: Answer (2) From the Average form of Newton's law of cooling, we can write:

### In an astronomical telescope in normal adjustment a straight black line of the length L is drawn on inside part of objective lens. The eye-piece forms a real image of this line. The length of this image is 1 . The magnification of the telescope is: (1) (2) (3) (4)

$ \begin{array}{l} \mathrm{m}=\frac{f}{\mathrm{f}+\mathrm{u}} \\...

### Water rises to a height ‘ ‘ in capillary tube. If the length of capillary tube above the surface of water is made less than ‘ ‘, then: (1) Water does not rise at all (2) Water rises upto the tip of capillary tube and then starts overflowing like a fountain (3) Water rises upto the top of capillary tube and stays there without overflowing (4) Water rises upto a point a little below the top and stays there

Solution: (3) Water will not overflow, but its radius of curvature will vary. Explanation: It won't overflow. That should be obvious since doing so would create a constant flow, constantly using...

### A circuit contains an ammeter, a battery of and a resistance all connected in series. If the ammeter has coil of resistance 480 ohm and a shunt of , the reading in the ammeter will be: (1) (2) (3) (4)

Solution: (2) Resistance of ammeter $=\frac{480 \times 20}{480+20}=19.2 \Omega$ $ i=\frac{30}{40.8+19.2}=0.5 \mathrm{~A} $

### If dimensions of critical velocity of a liquid flowing through a tube are expressed as , where and are the coefficient of viscosity of liquid, density of liquid and radius of the tube respectively, then the values of and are given by: (1) (2) (3) (4)

Solution: (2) $ \mathrm{V}_{\mathrm{c}}=\eta^{\mathrm{x}} \rho^{\mathrm{y}} \mathrm{r}^{\mathrm{z}} $ Critical velocity is given by $V_{c}=\frac{R \eta}{2 \rho r}$ So, $x=1$ $ \begin{aligned} y=-1...

### The number of photons per second on an average emitted by the source of monochromatic light of wavelength 600 nm, when it delivers the power of 3.3 × 10–3 watt will be

(h = 6.6 × 10–34 J s) (1) 1018 (2) 1017 (3) 1016 (4) 1015 Solution: Answer (3) The power of a source is given by the expression:...

### The input signal given to a CE amplifier having a voltage gain of 150 is . The corresponding output signal will be: (1) (2) (3) (4)

Solution: (1) The phase difference caused by CE amplifier $\pi\left(=180^{\circ}\right)$ so $V_{\text {out }}=300 \cos \left(15 t+\frac{\pi}{3}+\pi\right)$

### A proton and an alpha particle both enter a region of uniform magnetic field B, moving at right angles to the field B. if the radius of circular orbits for both the particles is equal and the kinetic energy acquired by proton is , the energy acquired by the alpha particle will be: (1) (2) (3) (4)

Solution: (1) $ \mathrm{R}=\frac{\mathrm{mV}}{\mathrm{qB}}=\frac{\sqrt{2 \mathrm{~m}(\mathrm{kE})}}{\mathrm{qB}} $ Since $\mathrm{R}$ is same so $\mathrm{KE} \propto...

### The heart of a man pumps 5 litres of blood through the arteries per minute at a pressure of of mercury. If the density of mercury be and then the power of heart in watt is: (1) (2) (3) (4)

Solution: (2) $ \begin{aligned} \text { Power } &=\vec{F}, \vec{V}=P A \vec{V}=\rho g h A V \\ &=13.6 \times 10^{3} \times 10 \times 150 \times 10^{-3} \times 0.5 \times 10^{-3} /_{60} \text...

### Two slits in Young’s experiment have widths in the ratio . The ratio of intensity at the maxima and minima in the interference pattern, is: (1) (2) (3) (4)

Solution: (2) $ \begin{array}{l} \frac{I_{1}}{I_{2}}=\frac{25}{1} \Rightarrow \frac{A_{1}}{A_{2}}=\frac{5}{1} \\ \frac{A_{\max }}{A_{\min }}=\frac{5+1}{5-1}=\frac{6}{4}=\frac{3}{2} \\ \frac{I_{\max...

### Two charged spherical conductors of radius R1 and R2 are connected by a wire. Then the ratio of surface charge densities of the spheres (s1/s2) is

$ (1)\,\,\frac{{{R}_{1}}}{{{R}_{2}}} $ $ (2)\,\,\frac{{{R}_{2}}}{{{R}_{1}}} $ $ (3)\,\,\sqrt{\frac{{{R}_{1}}}{{{R}_{2}}}} $ $ (4)\,\,\frac{{{R}^{2}}_{1}}{{{R}^{2}}_{2}} $ Solution: Answer...

### If potential (in volts) in a region is expressed as , the electric field (in at point is: (1) (2) (3) (4)

Solution: (3) $ \begin{array}{l} V=6 x y-y+24 z \\ \bar{E}=\left(\frac{\partial V}{\partial x} \hat{1}+\frac{\partial V}{\partial y} \hat{j} \frac{\partial V}{\partial z} \hat{k}\right) \\...

### On a frictionless surfaces, a block of mass moving at speed collides elastically with another block of same mass which is initially at rest. After collision the first block moves at an angle to its initial direction and has a speed . The second block’s speed after the collision is: (1) (2) (3) (4)

Solution: (2) $\overrightarrow{\mathrm{P}}_{1}=\overrightarrow{\mathrm{P}_{\mathrm{f}}}$ $\Rightarrow\left|\mathrm{P}_{\mathrm{i}}\right|=\left|\mathrm{P}_{\mathrm{f}}\right| \Rightarrow...

### A ball is thrown vertically downwards from a height of with an initial velocity . It collides with the ground, loses 50 percent of its energy in collision and rebounds to the same height. The initial velocity is: (Take ) (1) (2) (3) (4)

Solution: (3) $ \begin{array}{l} \frac{K E_{f}}{\mathbb{K E}_{i}}=\frac{1}{2} \\ \frac{V_{f}}{V_{i}}=\frac{1}{\sqrt{2}} \\ \frac{\sqrt{2 g h}}{\sqrt{V_{0}^{2}+2 g h}}=\frac{1}{\sqrt{2}} \end{array}...

### An ideal gas is compressed to half its initial volume by means of several processes. Which of the process results in the maximum work done on the gas? (1) Isothermal (2) Adiabatic (3) Isobaric (4) Isochoric

Solution: (2) Because the adiabatic process has the largest area under the curve, the amount of work done on the gas is also the largest.

### A thick current carrying cable of radius ‘R’ carries current ‘I’ uniformly distributed across its crosssection. The variation of magnetic field B(r) due to the cable with the distance ‘r’ from the axis of the cable is represented by

Solution: Answer (3) From Ampere's circuital law, we know that: $ B=\frac{{{\mu }_{0}}I}{2\pi {{R}^{2}}}.r\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,if\,r<R $ $ B=\frac{{{\mu...

### The coefficient of performance of a refrigerator is 5 . If the temperature inside freezer is , the temperature of the surrounding to which is rejects heat is: (1) (2) (3) (4)

Solution: (2) $ \begin{array}{l}...

### Two stones of masses ma and are whirled in horizontal circles, the heavier one in a radius and the lighter one in radius r. the tangential speed of lighter stone is times that of the value of heavier stone when they experience same centripetal forces. The value of is: (1) 1 (2) 2 (3) 3 (4) 4

The Solution is (2) $ \mathrm{F}_{\mathrm{C}}=\frac{\mathrm{mv}_{1}^{2}}{\mathrm{r}}=\frac{2 \mathrm{mv}_{2}^{2}}{\left(\frac{\mathrm{r}}{2}\right)}=\frac{4 \mathrm{mv}_{2}^{2}}{\mathrm{r}} $...

### A plank with a box on it at one end is gradually raised about the other end. As the angle of inclination with the horizontal reaches , the box starts to slip and slides down the plank in . The coefficients of static and kinetic friction between the box and the plank will be, respectively: (1) and (2) and (3) and (4) and

The Solution is (3) $ \begin{array}{l} \mu_{s}=\tan 30^{\circ}=\frac{1}{\sqrt{3}}=0.5 \\ \mu_{s}=0.57=0.6 \\ \mathrm{~S}=\mathrm{ut}+\frac{1}{2} \mathrm{at}^{2} \\ 4=\frac{1}{2} a(4)^{2} \Rightarrow...

### A screw gauge gives the following readings when used to measure the diameter of a wire Main scale reading : 0 mm Circular scale reading : 52 divisions Given that 1 mm on main scale corresponds to 100 divisions on the circular scale. The diameter of the wire from the above data is

(1) 0.52 cm (2) 0.026 cm (3) 0.26 cm (4) 0.052 cm Solution: Answer (4) According to the question, the pitch of the screw gauge, P = 1 mm The...

### A series R-C circuit is connected to an alternating voltage source. Consider two situations: i. When capacitor is air filled. ii. When capacitor is mica filled. Current through resistor is and voltage across capacitor is then: (1) (2) (3) (4)

Solution: (3) $ \begin{array}{l} X_{c}=1 / \mathrm{C} \mathrm{N} \end{array} $ $ \begin{array}{l} i=\frac{v}{\sqrt{R^{2}+\left(\frac{1}{c \omega}\right)^{2}}} \\...