AIPMT 2012 Chemistry Past Paper PDF

Summary

This is an AIPMT 2012 chemistry past paper. The paper contains 15 questions and covers various topics in chemistry, including chemical reactions, kinetics, equilibrium, and thermodynamics.

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MyCollegeBag.in The Best Place for Free And Fare Education Test Booklet Code B Important Instructions 1. The Answer Sheet is inside this test Booklet. When you are directed to open the Test Booklet, take out the A...

MyCollegeBag.in The Best Place for Free And Fare Education Test Booklet Code B Important Instructions 1. The Answer Sheet is inside this test Booklet. When you are directed to open the Test Booklet, take out the Answer Sheet and fill in the particulars on side-1 and side-2 carefully with blue/black ball point pen only. 2. The Test is of 3 hours duration and Test Booklet contains 200 questions. Each question carries 4 marks. For each correct response, the candidate will get 4 marks. For each incorrect response, one mark will be deducted from the total scores. The maximum marks are 800. 3. Use Blue/Black Ball Point Pen only for writing particulars on this page/marking responses. 4. Rough work is to be done on the space provided for this purpose in the Test Booklet only. 5. On completion of the test, the candidate must handover the Answer Sheet to the invigilator in the Room/Hall. The candidates are allowed to take away this Test Booklet with them. 6. The CODE for this Booklet is B. Make sure that the CODE printed on Side-2 of the Answer Sheet is the same as that on this Booklet. In case of discrepancy, the candidate should immediately report the matter to the Invigilator for replacement of both the Test Booklets and the Answer Sheets. 7. The candidates should ensure that the Answer Sheet is not folded. Do not make any stray marks on the Answer Sheet. Do not write your roll no. anywhere else except in the specified space in the Test Booklet/ Answer Sheet. 8. Use of white fluid for correction is NOT permissible on the Answer Sheet. 9. Each Candidate must show on demand his/her Admission Card to the Invigilator. 10. No candidate, without special permission of the Superintendent or Invigilator, would leave his/her seat. 11. The candidates should not leave the Examination Hall without handing over their Answer Sheet to the Invigilator on duty and sign the Attendance Sheet twice. Cases where a candidate has not signed the Attendance Sheet the second time will be deemed not to have handed over Answer Sheet and dealt with as an unfair means case. 12. Use of Electronic/Manual Calculator is prohibited. 13. The candidates are governed by all Rules and Regulations of the Board with regard to their conduct in the Examination Hall. All cases of unfair means will be dealt with as per Rules and Regulations of the Board. 14. No part of the Test Booklet and Answer Sheet shall be detached under any circumstances. 15. The candidates will write the Correct Test Booklet Code as given in the Test Booklet/Answer Sheet in the Attendance sheet. Name of the Candidate (in Capital Letters): _________________________________________________ Roll Number : in figure _______________________________________________________________ : in words _______________________________________________________________ Centre of Examination (in Capitals): _______________________________________________________ Candidate’s Signature : ________________________ Invigilator’s Signature _____________________ Fascimile signature stamp of Centre superintendent ___________________________________________ Visit:MyCollegeBag.in Free Coaching for HC Verma , Last Year question Paper, Sample Papers. MyCollegeBag.in The Best Place for Free And Fare Education CBSE - 2012 (Pre) CHEMISTRY CODE – B 1. CH3CHO and C6H5CH2CHO can be distinguished chemically by (1) Fehling solution test (2) Benedict test (3) Iodoform test (4) Tollen’s reagent test O || Sol: Aldehydes and ketones having CH  C  group give iodoform test. 3 O || CH3  C  H  3I 2  4NaOH  CHI3  HCOONa  3NaI  3H 2O Yellow ppt. 2. pA and pB are the vapour pressure of pure liquid components. A and B, respectively of an ideal binary solution. If xA represents the mole fraction of component A, the total pressure of the solution will be (1) pB + xA (pA – pB) (2) pA + xA (pB – pA) (3) pA + xA (pA – pB) (4) pB + xA (pB – pA) Sol: pTotal = pA  xA + pB  xB xB + xA = 1 xB = 1 – xA pTotal = pA  xA + pB(1 – xB) 3. Which one of the following is not a condensation polymer? (1) Neoprene (2) Melamine (3) Glyptal (4) Dacron Sol: Addition polymer of chloroprene is neoprene H2C Chloroprene is CH2 Cl 4. A metal crystallizes with a face-centered cubic lattice. The edge of the unit cell is 408 pm. The diameter of the metal atom is : (1) 204 pm (2) 288 pm (3) 408 pm (4) 144 pm a 408 Sol: 2a  4r  2    288pm 2 1.414 5. Equimolar solutions of the following substances were prepared separately. Which one of these will record the highest pH value? (1) BeCl2 (2) BaCl2 (3) AlCl3 (4) LiCl Sol: Salt of strong acid and strong base 6. In the following reaction: CH3  H 2O / H H3C C CH  A  B Major product Minor product CH3 CH2 Amity Institute for Competitive Examinations : Phones: 24336143/44, 25573111/2/3/4, 95120-2431839/42 -2 - Visit:MyCollegeBag.in Free Coaching for HC Verma , Last Year question Paper, Sample Papers. MyCollegeBag.in The Best Place for Free And Fare Education CBSE-2012 (Pre) Chemistry The major product is: CH3 CH3 CH3 H3C C CH2 H3C C HC (1) (2) CH3 CH2 OH OH CH3 HO CH3 CH3 CH3 CH2 C CH2 H3C C HC (3) (4) OH CH3 CH3 OH Sol: H H CH3 CH3 H3C CH3 O CH3 + 1,2alkyl + H O  H H H3C  H3C CH  shift C  H3C CH3 CH2 CH3 CH3 H3C CH3 CH3 CH3 -H+ OH CH3 H3C CH3 CH3 7. The enthalpy of fusion of water is 1.435 kcal/mol. The molar entropy change for the melting of ice at 0°C (1) 0.526 cal/(mol K) (2) 10.52 cal / (mol K) (3) 21.04 cal / (mol K) (4) 5.260 cal/(mol K) H f 1.435 103 Sol: Sfusion    5.256 cal / molK T 273 8. Limiting molar conductivity of NH4OH (i.e.  m (NH 4OH) ) is equal to: (1)  m (NH 4Cl)   m (NaOH)   m (NaCl) (2)  m (NH 4Cl)   m (NaCl)   m (NaOH) (3)  m (NaOH)   m (NaCl)   m (NH 4 Cl) (4)  m (NH 4 OH)   m (NH 4Cl)   m (HCl) Sol: 0m (NH 4Cl)  0m (NaOH)  0m (NaCl) Self explained 9. Which one of the following is a mineral of iron? (1) Magnetite (2) Malachite (3) Cassiterite (4) Pyrolusite Sol: Magnetite (Fe3O4 ) 10. In Freundlich Adsorption isotherm, the value of 1/n is: (1) 1 in case of chemisorption (2) between 0 and 1 in all cases (3) between 2 and 4 in all cases (4) 1 in case of physical adsorption x Sol:  Kp1/ n m Amity Institute for Competitive Examinations : Phones: 24336143/44, 25573111/2/3/4, 95120-2431839/42 -3 - Visit:MyCollegeBag.in Free Coaching for HC Verma , Last Year question Paper, Sample Papers. MyCollegeBag.in The Best Place for Free And Fare Education CBSE-2012 (Pre) Chemistry 11. Identify the alloy containing a non-metal as a constituent in it. (1) Bronze (2) Invar (3) Steel (4) Bell metal Sol: In steel, C is also present 12. Buffer solutions have constant acidity and alkalinity because: (1) they have fixed value of pH (2) these give unionised acid or base on reaction with added acid or alkali (3) acids and alkalies in these solutions are shielded from attack by other ions (4) they have large excess of H+ or OH– ions Sol: Self explanatory 13. Which one of the following pairs is isostructural (i.e. having the same shape and hybridization)? (1) [BF4 and NH4 ] (2) [BCl3 and BaCl3 ] (3) [NH 3 and NO3 ] (4) [NF3 and BF3] Sol: In both the compounds, central atom is sp3 hybridized and structure is tetrahedral. 14. pH of a saturated solution of Ba(OH)2 is 12. The value of solubility product (Ksp) of Ba(OH)2 is (1) 5.0 × 10–6 (2) 3.3 × 10–7 (3) 5.0 × 10–7 (4) 4.0 × 10–6 Sol: pH = 12 pOH = 2  [OH–] = 10–2  Ba 2  2OH  Ba(OH) 2  2x = 10–2 x 2x x = 5 × 10–3 Ksp = x (2x)2 = 5 × 10-3 × (10–2)2 = 5 × 10–7 15. 50 mL of each gas A and of gas B takes 150 and 200 seconds respectively for effusing through a pin hole under the similar conditions. If molecular mass of gas B is 36, the molecular mass of gas A will be (1) 64 (2) 96 (3) 128 (4) 32 Sol: However question is wrong. 16. The protecting power of lyophilic colloidal sol is expressed in terms of (1) Oxidation number (2) Coagulation value (3) Gold number (4) Critical miscelle concentration Sol: Factual 17. Deficiency of vitamin B1 causes the disease (1) Sterility (2) Convulsions (3) Beri-Beri (4) Cheilosis Sol: Factual 18. Acetone is treated with excess of ethanol in the presence of hydrochloric acid. The product obtained is: H3C O C2 H5 H3C CH2 O C CH2 C (1) (2) H3C O C2 H5 CH3 H3C CH2 O CH2 C H3C OH (3) CH2 CH2 (4) C H3C O C2 H5 CH3 Sol: Amity Institute for Competitive Examinations : Phones: 24336143/44, 25573111/2/3/4, 95120-2431839/42 -4 - Visit:MyCollegeBag.in Free Coaching for HC Verma , Last Year question Paper, Sample Papers. MyCollegeBag.in The Best Place for Free And Fare Education CBSE-2012 (Pre) Chemistry 19. The ease of adsorption of the hydrated alkali metal ions on an ion-exchange resins follows the order: (1) Na+ < Li+ < K+ < Rb+ (2) Li+ < K+ < Na+ < Rb+ (3) Rb+ < K+ < Na+ < Li+ (4) K+ < Na+ < Rb+ < Li+ Sol: Greater the size of the hydrated ion, more will be the surface area and more will be its ease of adsorption. 20. Which one of the following statements is incorrect about enzyme catalysis? (1) Enzymes are least reactive at optimum temperature (2) Enzymes are mostly proteinous in nature (3) Enzyme action is specific (4) Enzymes are denaturated by ultraviolet rays and at high temperature Sol: Enzyme is most active at optimum temperature and pH 21. In which of the following compounds, nitrogen exhibits highest oxidation state? (1) NH 2 OH (2) N 2 H 4 (3) NH 3 (4) N 3 H Sol: Oxidation state of N is N3H = –1/3 22. Bond order of 1.5 is shown by: (1) O 2 (2) O2 (3) O2 (4) O22 1 1 Sol: Bond Order = (N b  N a )  (10  7)  1.5 2 2 23. Maximum number of electrons in a subshell with l = 3 and n = 4 is: (1) 12 (2) 14 (3) 16 (4) 10 Sol: i.e. 4f maximum number of electrons that can be accommodated in f-subshell = 14 24. The correct set of four quantum numbers for the valence electron of rubidium atom (Z = 37) is (1) 5, 1, 0, +1/2 (2) 5, 1, 1, +1/2 (3) 6, 0, 0, +1/2 (4) 5, 0, 0, +1/2 Sol: i.e. [Kr]5s1 so n = 5, l = 0, m = 0, s = +1/2 25. In a reaction, A + B  Product, rate is doubled when the concentration of B is doubled, and rate increases by a factor of 8 when the concentrations of both the reactants (A and B) are doubled, rate law for the reaction can be written as: (1) Rate = k[A]2 [B] (2) Rate = k[A] [B]2 (3) Rate = k[A]2 [B]2 (4) Rate = k[A] [B] Sol: A + B Product r1  [A]x [B]y r2  [A]x [2B]y  2r1  2  [A]x [B]y  2 y  2  y  1 r3  [2A]x [2B]y  8r1  8  [A]x [B]y = 2x × 2y = 23 = 2x = 22 Rate = k [A]2 [B] 26. A mixture of potassium chlorate, oxalic acid and sulphuric acid is heated. During the reaction which element undergoes maximum change in the oxidation number? (1) C (2) S (3) H (4) Cl Sol: ClO3 changes to Cl– Cl5  Cl1 Amity Institute for Competitive Examinations : Phones: 24336143/44, 25573111/2/3/4, 95120-2431839/42 -5 - Visit:MyCollegeBag.in Free Coaching for HC Verma , Last Year question Paper, Sample Papers. MyCollegeBag.in The Best Place for Free And Fare Education CBSE-2012 (Pre) Chemistry 27. Which one of the following sets of monosaccharides forms sucrose? (1) -D-Glucopyranose and -D-fructopyranose (2) -D-Galactopyranose and -D-Glucopyranose (3) -D-Glucopyranose and -D-fructofuranose (4) -D-Glucopyranose and -D-fructofuranose CH2 OH H CH2 OH H O CH2 OH O H H OH OH H Sol: HO O H H OH   OH OH 28. Which one of the following statements regarding photochemical smog is not correct? (1) Photochemical smog does not cause irritation in eyes and throat (2) Carbon monoxide does not play any role in photochemical smog formation (3) Photochemical smog is an oxidizing agent in character (4) Photochemical smog is formed through photochemical reaction involving solar energy. Sol: Factual 29. Which of the following statements is not valid for oxoacids of phosphorus? (1) All oxoacids contain atleast one P = O unit and one P – OH group (2) Orthophosphoric acid is used in the manufacture of triple superphosphate. (3) Hypophosphorous acid is a diprotic acid. (4) All oxoacids contain tetrahedral four coordinated phosphorous O HO P OH Sol: H  KCN H 3O LiAlH4 30. In the following sequence of reactions CH3  Br  A  B  ether C, the end product (C) is (1) Ethyl alcohol (2) Acetone (3) Methane (4) Acetaldehyde  KCN H 3O LiAlH 4 Sol: [a] CH3  Br  CH 3CN  CH 3COOH  CH3  CH 2  OH (A) (B) (C) 31. Which of the following acids does not exhibit optical isomerism? (1) Tartaric acid (2) Maleic acid (3) -amino acids (4) Lactic acid HOOC COOH Maleic acid will not show optical isomerism Sol: due to absence of H H chirality. Amity Institute for Competitive Examinations : Phones: 24336143/44, 25573111/2/3/4, 95120-2431839/42 -6 - Visit:MyCollegeBag.in Free Coaching for HC Verma , Last Year question Paper, Sample Papers. MyCollegeBag.in The Best Place for Free And Fare Education CBSE-2012 (Pre) Chemistry 32. Which nomenclature is not according to IUPAC system? H3C CH2 CH2 OH C CH2 C Br CH CH2 CH2 (1) O O (2) 1-Bromo-prop-2-ene 5-oxohexanoic acid H3C CH3 CH3 CH3 CH HC H3C CH2 C CH2 HC H3C (3) Br CH3 (4) 4-bromo-2,4-dimethylhexane 2-methylpentan-3-ylbenzene Sol: The correct name of compound will be 3-Bromoprop-1-ene 33. The pair of species with the same bond order is (1) N2, O2 (2) O22 , B2 (3) O2 , NO (4) NO, CO Sol: O22  B.O.  1 B2  B.O.  1 34. In the extraction of copper from its sulphide ore, the metal is finally obtained by the reduction of cuprous oxide with: (1) Carbon monoxide (CO) (2) Copper (I) sulphide (Cu2S) (3) Sulphur dioxide (SO2) (4) Iron sulphide (FeS) Sol: Cu2O is reduced with Cu2S It is self reduction phenomena 35. The correct order of decreasing acid strength of trichloroacetic acid (A), trifluoroacetic acid (B), acetic acid (C) and formic acid (D) is: (1) A > C > B > D (2) B > A > D > C (3) B > D > C > A (4) A > B > C > D Sol: Due to –I effect. 36. Aluminium is extracted from alumina (Al2O3) by electrolysis of a molten mixture of : (1) Al2O3 + KF + Na3AlF6 (2) Al2O3 + HF + NaAlF4 (3) Al2O3 + CaF2 + NaAlF4 (4) Al2O3 + Na3AlF6 + CaF2 Sol: Alumina + Fluorspar + Cryolite 37. Which of the following species contains three bond pairs and one lone pair around the central atom? (1) PCl3 (2) H 2 O (3) BF 3 (4) NH2 Sol: P Cl Cl Cl Amity Institute for Competitive Examinations : Phones: 24336143/44, 25573111/2/3/4, 95120-2431839/42 -7 - Visit:MyCollegeBag.in Free Coaching for HC Verma , Last Year question Paper, Sample Papers. MyCollegeBag.in The Best Place for Free And Fare Education CBSE-2012 (Pre) Chemistry 38. Which of the following statements is false? (1) Both starch and cellulose are polymers of glucose (2) Artificial silk is derived from cellulose (3) Nylon-66 is an example of elastomer (4) The repeat unit in natural rubber is isoprene Sol: Factual 39. The number of octahedral void(s) per atom present in a cubic close-packed structure is (1) 4 (2) 1 (3) 3 (4) 2 Sol: In ccp the no. of atoms present per unit cell is 4 and total no. of O.V = 4 per atom the no. of O.V. = 1 40. Among the following compounds the one that is most reactive towards electrophilic nitration is: (1) Benzene (2) Benzoic acid (3) Nitrobenzene (4) Toluene CH3 Sol: In , CH3 is ortho para directing and also ring activator.. 41. Identify the wrong statement in the following: (1) Atomic radius of the elements decreases as one moves across from left to right in the 2nd period of the periodic table (2) Amongst isoelectronic species, smaller the positive charge on the carbon, smaller is the ionic radius (3) Amongst isoelectronic species, greater the negative charge on the anion, larger is the ionic radius (4) Atomic radius of the elements increases as one moves down the first group of the periodic table. Sol: With increasing positive charge, effective nuclear charge increases so ionic radii decreases. 42. In a zero-order reaction for every 10° rise of temperature, the rate is doubled. If the temperature is increased from 10°C to 100°C, the rate of the reaction will become: (1) 128 times (2) 256 times (3) 512 times (4) 64 times r2 Sol:  2 for every 10° r1 Temperature is raised from 10° to 100° T rn So  2 10  29 r1 rn  r1  512 43. Which of the statements is not true? (1) K 2Cr2O7 solution becomes yellow on increasing the pH beyond 7 (2) On passing H2S through acidified K2Cr2O7 solution, a milky colour is observed (3) Na2Cr2O7 is preferred over K2Cr2O7 in volumetric analysis (4) K2Cr2O7 solution in acidic medium is orange Sol: Factual Amity Institute for Competitive Examinations : Phones: 24336143/44, 25573111/2/3/4, 95120-2431839/42 -8 - Visit:MyCollegeBag.in Free Coaching for HC Verma , Last Year question Paper, Sample Papers. MyCollegeBag.in The Best Place for Free And Fare Education CBSE-2012 (Pre) Chemistry 44. In which of the following reactions, standard reaction entropy change (S°) is positive and standard Gibb’s energy change (G°) decreases sharply with increasing temperature? 1 1 1 1 (1) C graphite  O2 (g)  CO 2 (g) (2) C graphite  O2 (g)  CO(g) 2 2 2 2 1 1 (3) CO(g)  O 2 (g)  CO 2 (g) (4) Mg(s)  O 2 (g)  MgO(s) 2 2 1 Sol: C(g)  O2 (g)  CO(g) 2 S° = +ve 45. When Cl2 gas reacts with hot and concentrated sodium hydroxide solution, the oxidation number of chlorine changes from (1) Zero to + 1 and zero to –3 (2) Zero to +1 and zero to –5 (3) Zero to –1 and zero to + 5 (4) Zero –1 and zero to + 3 Sol: Cl2  NaOH(hot conc.)  NaCl  NaClO3 In NaCl , oxidation no. of Cl is –1 and in ClO3 , oxidation no. of Cl is +5 46. Predict the products in the given reaction CHO 50% KOH  Cl O O - OH OH O  -  O (1) (2) Cl Cl OH OH O OH OH - OH O   (3) (4) OH OH Cl Cl OH CHO COOK Sol: 50% KOH   Cl Cl Cl Amity Institute for Competitive Examinations : Phones: 24336143/44, 25573111/2/3/4, 95120-2431839/42 -9 - Visit:MyCollegeBag.in Free Coaching for HC Verma , Last Year question Paper, Sample Papers. MyCollegeBag.in The Best Place for Free And Fare Education CBSE-2012 (Pre) Chemistry 47. Which one of the alkali metals, forms only, the normal oxide, M2O on heating in air (1) Na (2) Rb (3) K (4) Li Sol: Li  O2  Li 2O Other forms peroxides and super oxides also 48. Which one of the following is an outer orbital complex and exhibits paramagnetic behaviour? (1) [Co(NH3 )6 ]3+ (2) [Ni(NH3)6 ]2+ (3) [Zn(NH3 )6 ]2+ (4) [Cr(NH3 )6 ]3+ Sol: [Ni(NH3 )6 ]2+ Here in Ni2+ the configuration is 3d8 4s0 4p0 4d 0 sp3d2 bybridized Hence it gives outer orbital octahedral complex which is paramagnetic 49. Sulphur trioxide can be obtained by which of the following reaction:   (1) H2SO4  PCl5  (2) CaSO4  C    (3) Fe2 (SO4 )3  (4) S  H 2SO4   Sol: Fe2 (SO4 ) 3  3SO3  Fe 2O3 50. Standard enthalpy of vapourisation vapH– for water at 100°C is 40.66 kJmol–1. The internal energy of vapourisation of water at 100°C (in kJ mol–1) is (1) +40.66 (2) +37.56 (3) –43.76 (4) +43.76 Sol: H2 O(l)  H 2 O(g) V1 of liq. H2O = 18 ml nRT and V2 of H2O (vap) = P 1 0.0821 373   30.6233 lit 1 V = (30623.3 ml – 18 ml) = 30605.3 ml = 30.605 lit E = H – PV = 40.66 × 103J – 1 × 30.605 × 101.325 J = 36557.9 = 37.5589 kJ mol–1  Amity Institute for Competitive Examinations : Phones: 24336143/44, 25573111/2/3/4, 95120-2431839/42 - 10 - Visit:MyCollegeBag.in Free Coaching for HC Verma , Last Year question Paper, Sample Papers. MyCollegeBag.in The Best Place for Free And Fare Education CBSE - 2012 (Pre) BIOLOGY CODE – B 51. Removal of introns and joining of exons in a defined order during transcription in called (1) Splicing (2) Looping (3) Inducing (4) Slicing Ans. 52. Common cold differs from pneumonia in, that (1) Pneumonia pathogen infects alveoli whereas the common cold affects nose and respiratory passage but not the lungs (2) Pneumonia is a communicable disease whereas the common cold is a nutritional deficiency disease (3) Pneumonia can be prevented by a live attenuated bacterial vaccine whereas the common cold has no effective vaccine (4) Pneumonia is caused by a virus while the common cold is caused by the bacterium Haemophilus influenzae Ans. 53. Which one of the following in not a property of cancerous cells whereas the remaining three are ? (1) They show contact inhibition (2) They compete with normal cells for vital nutrients (3) They do not remain confined in the area of formation (4) They divide in an uncontrolled manner Ans. 54. How many plants in the list given below have composite fruits that develop from an inflorescence ? Walnut, poppy, radish, fig, pineapple, apple, tomato, mulberry. (1) Three (2) Four (3) Five (4) Two Ans. 55. An organic substance that can withstand environmental extremes and cannot be degraded by any enzyme is (1) Cellulose (2) Cuticle (3) Sporopollenin (4) Lignin Ans. 56. Both, autogamy and geitonogamy are prevented in (1) Maize (2) Papaya (3) Cucumber (4) Castor Ans. 57. Which part of the human ear plays no role in hearing as such but is otherwise very much required ? (1) Ear ossicles (2) Eustachian tube (3) Organ of Corti (4) Vestibular apparatus Ans. 58. Water containing cavities in vascular bundles are found in (1) Pinus (2) Sunflower (3) Maize (4) Cycas Ans. 59. Which one of the following is a case of wrong matching ? (1) Callus - Unorganised mass of cells produced in tissue culture (2) Somatic hybridization - Fusion of two diverse cells (3) Vector DNA - Site for t-RNA synthesis (4) Micropropagation - In vitro production of plants in large numbers Ans. Amity Institute for Competitive Examinations : Phones: 24336143/44, 25573111/2/3/4, 95120-2431839/42 - 11 - Visit:MyCollegeBag.in Free Coaching for HC Verma , Last Year question Paper, Sample Papers. MyCollegeBag.in The Best Place for Free And Fare Education CBSE-2012 (Pre) Biology 60. Which one out of A – D given below correctly represents the structural formula of the basic amino acid? A B C D NH2 NH2 CH2OH NH2 H – C – COOH H – C – COOH CH2 H – C – COOH CH2 CH2 CH2 CH2 CH2 OH NH2 CH2 C CH2 O OH CH2 NH2 Options : (1) B (2) C (3) D (4) A Ans. (3) 61. A patient brought to a hospital with myocardial infarction is normally immediately given (1) Statins (2) Penicillin (3) Streptokinase (4) Cyclosporin–A Ans. (3) 62. What is the figure given below showing in particular ? (1) Vasectomy (2) Ovarian cancer (3) Uterine cancer (4) Tubectomy Ans. 63. Ribosomal RNA is actively synthesized in (1) Ribosomes (2) Lysosomes (3) Nucleolus (4) Nucleoplasm Ans. (3) 64. Which one of the following does not differ in E.coli and Chlamydomonas ? (1) Cell membrane (2) Ribosomes (3) Chromosomal Organization (4) Cell wall Ans. 65. Which one is the most abundant protein in the animal world ? (1) Insulin (2) Trypsin (3) Haemoglobin (4) Collagen Ans. 66. Consumption of which one of the following foods can prevent the kind of blindness associated with vitamin ‘A’ deficiency ? (1) Bt-Brinjal (2) ‘Flaver Savr’ tomato (3) Canolla (4) Golden rice Ans. Amity Institute for Competitive Examinations : Phones: 24336143/44, 25573111/2/3/4, 95120-2431839/42 - 12 - Visit:MyCollegeBag.in Free Coaching for HC Verma , Last Year question Paper, Sample Papers. MyCollegeBag.in The Best Place for Free And Fare Education CBSE-2012 (Pre) Biology 67. Which one of the following options gives one correct example each of convergent evolution and divergent evolution ? Convergent evolution Divergent evolution (1) Thorns of Bougainvillia and Eyes of Octopus and mammals tendrils of Cucurbita (2) Eyes of octopus and mammals Bones of forelimbs of vertebrates (3) Thorns of Bougainvillia and Wings of butterflies and birds tendrils of Cucurbita (4) Bones of forelimbs of Wings of butterfly and birds vertebrates Ans. 68. The gynoecium consists of many free pistils in flowers of (1) Michelia (2) Aloe (3) Tomato (4) Papaver Ans. 69. Evolution of different species in a given area starting from a point and spreading to other geographical areas is known as (1) Divergent evolution (2) Adaptive radiation (3) Natural selection (4) Migration Ans. 70. Which one of the following statements is false in respect of viability of mammalian sperm ? (1) Sperms must be concentrated in a thick suspension (2) Sperm is viable for only up to 24 hours (3) Survival of sperm depends on the pH of the medium and is more active in alkaline medium (4) Viability of sperm is determined by its motility Ans. 71. A single strand of nucleic acid tagged with a radioactive molecule is called (1) Probe (2) Vector (3) Selectable marker (4) Plasmid Ans. 72. Measuring Biochemical Oxygen Demand (BOD) is a method used for (1) Working out the efficiency of R.B.Cs. about their capacity to carry oxygen (2) Estimating the amount of organic matter is sewage water (3) Working out the efficiency of oil driven automobile engines (4) Measuring the activity of Sacccharomyces cerevisae in producing curd on a commercial scale Ans. 73. Yeast is used in the production of (1) Cheese and butter (2) Citric acid and lactic acid (3) Lipase and pectinase (4) Bread and beer Ans. 74. In an area where DDT had been used extensively, the population of birds declined significantly because (1) Many of the birds eggs laid, did not hatch (2) Birds stopped laying eggs (3) Earthworms in the area got eradicated (4) Cobras were feeding exclusively on birds Ans. 75. Pheretima and its close relatives derive nourishment from (1) Small pieces of fresh fallen leaves of maize, etc (2) Sugarcane roots (3) Decaying fallen leaves and soil organic matter (4) Soil insects Ans. (3) Amity Institute for Competitive Examinations : Phones: 24336143/44, 25573111/2/3/4, 95120-2431839/42 - 13 - Visit:MyCollegeBag.in Free Coaching for HC Verma , Last Year question Paper, Sample Papers. MyCollegeBag.in The Best Place for Free And Fare Education CBSE-2012 (Pre) Biology 76. People who have migrated from the planes to an area adjoining Rohtang Pass about six months back (1) Have the usual RBC count but their haemoglobin has very high binding affinuty of O2 (2) Have more RBCs and their haemoglobin has a lower binding affinity of O2 (3) Are not physically fit to play games like football (4) Suffer from altitude sickness with symptoms like nausea, fatigue, etc Ans. 77. Which one of the following is correctly matched ? (1) Bakane of rice seedlings – F.Skoog (2) Passive transport of nutrients – ATP (3) Apoplast – Plasmodesmata (4) Potassium – Readily immobilisation Ans. 78. Maximum nutritional diversity is found in the group (1) Plantae (2) Fungi (3) Animalia (4) Monera Ans. 79. Which one of the following is common to multicellular fungi, filamentous algae and protonema of mosses ? (1) Multiplication by fragmentation (2) Diplontic life cycle (3) Members of kingdom Plantae (4) Mode of Nutrition Ans. 80. In which one of the following options the two examples are correctly matched with their particular type of immunity ? Examples Type of immunity (1) Mucus coating of epithelium Physiological barriers lining the urinogenital tract and the HCl in stomach (2) Polymorpho-nuclear leukocytes Cellular barriers and monocytes (3) Anti-tetanus and anti-snake bite Active immunity injections (4) Saliva in mouth and Tears in Physical barriers eyes Ans. 81. Which one of the following pairs of hormones are the examples of those that can easily pass through the cell membrane of the target cell and bind to a receptor inside it (mostly in the nucleus) (1) Cortisol, testosterone (2) Insulin, glucagon (3) Thyroxin, Insulin (4) Somatostatin, oxytocin Ans. 82. Closed vascular bundles lack (1) Pith (2) Ground tissue (3) Conjunctive tissue (4) Cambium Ans. 83. Which one of the following is wrong statement ? (1) Nitrosomonas and Nitrobacter are chemoautotrophs (2) Anabaena and Nostoc are capable of fixing nitrogen in free-living state also (3) Root nodule forming nitrogen fixers live as aerobes under free-living conditions (4) Phosphorus is a constituent of cell membranes, certain nucleic acids and all proteins Ans. Amity Institute for Competitive Examinations : Phones: 24336143/44, 25573111/2/3/4, 95120-2431839/42 - 14 - Visit:MyCollegeBag.in Free Coaching for HC Verma , Last Year question Paper, Sample Papers. MyCollegeBag.in The Best Place for Free And Fare Education CBSE-2012 (Pre) Biology 84. The figure below is the diagrammatic representation of the E.Coli vector pRB 322. Which one of the given options correctly identifies its certain component (s) ? (1) ampR, tetR- antibiotic resistance genes (2) ori-original restriction enzyme (3) rop-reduced osmotic pressure (4) Hind III, EcoRI-selectable markers Ans. 85. Which one of the following is a correct statement ? (1) Origin of seed habit can be traced in pteridophytes (2) Pteridophyte gametophyte has a protonemal and leafy stage (3) In gymnosperms female gametophyte is free-living (4) Antheridiophores and archegoniophores are present in pteridophytes Ans. 86. Widal Test is carred out to test (1) Typhoid fever (2) Malaria (3) Diabetes mellitus (4) HIV/AIDS Ans. 87. The maximum amount of electrolytes and water (70 – 80 percent) from the glomerular filtrate is reabsorbed in which part of the nephron ? (1) Descending limb of loop of Henle (2) Ascending limb of loop of Henle (3) Distal convoluted tubule (4) Proximal convoluted tubule Ans. 88. The Test-tube Baby Programme employs which one of the following techniques ? (1) Zygote intra fallopian transfer (ZIFT) (2) Intra cytoplasmic sperm injection (ICSI) (3) Intra uterine insemination (IUI) (4) Gamete intra fallopian transfer (GIFT) Ans. 89. Which one of the following is a wrong statement ? (1) Eutrophication is a natural phenomenon in freshwater bodies (2) Most of the forests have been lost in tropical areas (3) Ozone in upper part of atmosphere is harmful to animals (4) Greenhouse effect is a natural phenomenon Ans. (3) 90. Identify the possible line “A” in the following food chain : Plant insect frog “A” Eagle (1) Parrot (2) Rabbit (3) Wolf (4) Cobra Ans. 91. The human hind brain comprises three parts, one of which is (1) Hypothalamus (2) Spinal cord (3) Corpus callosum (4) Cerebellum Ans. 92. PCR and Restriction Fragment Length Polymorphism are the methods for (1) Genetic Fingerprinting (2) Study of enzymes (3) Genetic transformation (4) DNA sequencing Ans. 93. Which one of the following areas in India, is a hotspot of biodiversity ? (1) Western Ghats (2) Eastern Ghats (3) Gangetic Plain (4) Sunderbans Ans. Amity Institute for Competitive Examinations : Phones: 24336143/44, 25573111/2/3/4, 95120-2431839/42 - 15 - Visit:MyCollegeBag.in Free Coaching for HC Verma , Last Year question Paper, Sample Papers. MyCollegeBag.in The Best Place for Free And Fare Education CBSE-2012 (Pre) Biology 94. Phyllode is present in (1) Opuntia (2) Asparagus (3) Euphorbia (4) Australian Acacia Ans. 95. The highest number of species in the world is represented by (1) Lichens (2) Fungi (3) Mosses (4) Algae Ans. 96. Motile zygote of Plasmodium occurs in (1) Human liver (2) Gut of female Anopheles (3) Salivary glands of Anopheles (4) Human RBCs Ans. 97. Select the correct statement regarding the specific disorder of muscular or skeletal system (1) Gout-inflammation of joints due to extra deposition of calcium (2) Muscular dystrophy-age related shortening of muscles (3) Osteoporosis-decrease in bone mass and higher chances of fractures with advancing age (4) Myasthenia gravis-Auto immune disorder which inhibits sliding of myosin filaments Ans. 98. Vexillary aestivation is characteristic of the family (1) Brassicaceae (2) Fabaceae (3) Asteraceae (4) Solanaceae Ans. 99. Give below is the representation of a certain event at a particular stage of a type of cell division. Which is this stage ? (1) Both prophase and metaphases of mitosis (2) Prophase I during meiosis (3) Prophase II during meiosis (4) Prophase of Mitosis Ans. 100. Which statement is wrong for viruses ? (1) Antibiotics have no effect on them (2) All are parasites (3) All of them have helical symmetry (4) They have ability to synthesize nucleic acids and proteins Ans. 101. The correct sequence of cell organelles during photorespiration is (1) Chloroplast, -vacuole, -peroxisome (2) Chloroplast,-Golgibodies,-mitochondria (3) Chloroplast,-Rough Endoplasmic reticulum,-Dictyosomes (4) Chloroplast,-mitochondria,-peroxisome Ans. 102. Which one of the following is an example of carrying out biological control of pests/diseases using microbes ? (1) Lady bird beetle against aphids in mustard (2) Trichoderma sp. against certain plant pathgens (3) Nucleopolyhedrovirus against white rust in Brassica (4) Bt-cotton to increase cotton yield Ans. Amity Institute for Competitive Examinations : Phones: 24336143/44, 25573111/2/3/4, 95120-2431839/42 - 16 - Visit:MyCollegeBag.in Free Coaching for HC Verma , Last Year question Paper, Sample Papers. MyCollegeBag.in The Best Place for Free And Fare Education CBSE-2012 (Pre) Biology 103. The extinct human who lived 1,00,000 to 40,000 years ago, in Europe, Asia and parts of Africa, with short stature, heavy eye brows, retreating for heads, large jaws with heavy teeth, stocky bodies, a lumbering gait and stooped posture was (1) Ramapithecus (2) Homo habilis (3) Neanderthal human (4) Cro-magnan humans Ans. 104. A normal-visioned man whose father was colour-blind, marries a woman whose father was also colour-blind. They have their first child as a daughter. What are the chances that this child would be colour-blind ? (1) 50% (2) 100% (3) Zero percent (4) 25% Ans. 105. Best defined function of Manganese in green plants is (1) Water absorption (2) Photolysis of water (3) Calving cycle (4) Nitrogen fixation Ans. 106. Even in absence of pollinating agents seed-setting is assured in (1) Fig (2) Commellina (3) Zostera (4) Salvia Ans. 107. What was the most significant trend in the evolution of modern man (Homo sapiens) from his ancestors? (1) Upright posture (2) Shortening of jaws (3) Binocular vision (4) Increasing cranial capacity Ans. 108. The most abundant prokaryotes helpful to humans in marking curd from milk and in production of antibiotics are the ones categorised as (1) Heterotrophic bacteria (2) Cyanobacteria (3) Archaebacteria (4) Chemosynthetic autotrophs Ans. 109. A person entering an empty room suddenly finds a snake right in front on opening the door. Which one of the following is likely to happen in his neuro-hormonal control system ? (1) Sympathetic nervous system is activated releasing epinephrin and norepinephrin from adrenal cortex (2) Sympathetic nervous system is activated releasing epinephrin and norepinephrin from adrenal medulla (3) Neurotransmitters diffuse rapidly across the cleft and transmit a nerve impulse (4) Hypothalamus activates the parasympathetic division of brain Ans. 110. Which one single organisms or the pair of organisms is correctly assigned to its or their named taxonomic group ? (1) Nostoc and Anabaena are examples of protista (2) Paramecium and Plasmodium belong to the same kingdom as that of Penicillium (3) Lichen is a composite organism formed from the symbiotic association of an algae and a protozoan (4) Yeast used in making bread and beer is a fungus Ans. Amity Institute for Competitive Examinations : Phones: 24336143/44, 25573111/2/3/4, 95120-2431839/42 - 17 - Visit:MyCollegeBag.in Free Coaching for HC Verma , Last Year question Paper, Sample Papers. MyCollegeBag.in The Best Place for Free And Fare Education CBSE-2012 (Pre) Biology 111. In a normal pregnant woman, the amount of total gonadotropin activity was assessed. The result expected was (1) High level of circulating HCG to stimulate estrogen and progesterone synthesis (2) High level of circulating FSH and LH in the uterus to stimulate implantation of the embryo (3) High level of circulating HCG to stimulate endometrial thickening (4) High levels of FSH and LH in uterus to stimulate endometrial thickening Ans. 112. Which part would be most suitable for raising virus-free plants for micropropagation ? (1) Node (2) Bark (3) Vascular tissue (4) Meristem Ans. 113. The Leydig cells as found in the human body are the secretory source of (1) Androgens (2) Progesterone (3) Intestinal mucus (4) Glucagon Ans. 114. Which one of the following is not a part of a transcription unit in DNA ? (1) The structural gene (2) The inducer (3) A terminator (4) A promoter Ans. 115. Gymnosperms are also called soft wood spermatophytes because they lack (1) Xylem fibres (2) Cambium (3) Phloem fibres (4) Thick-walled tracheids Ans. 116. Cycas and Adiantum resemble each other in having (1) Vessels (2) Seeds (3) Motile Sperms (4) Cambium Ans. 117. A certain road accident patient with unknown blood group needs immediate blood transfusion. His one doctor friend at once offers his blood. What was the blood group of the donor ? (1) Blood group A (2) Blood group B (3) Blood group AB (4) Blood group O Ans. 118. Compared to those of humans, the erythrocytes in frog are (1) Nucleated and without haemoglobin (2) Without nucleus but with haemoglobin (3) Nucleated and with haemoglobin (4) Very much smaller and fewer Ans. 119. A nitrogen-fixing microbe associated with Azolla in rice fields is (1) Tolypothrix (2) Spirulina (3) Anabaena (4) Frankia Ans. 120. What is correct to say about the hormone action in humans ? (1) FSH stimulates the secretion of estrogen and progesterone (2) Glucagon is secreted by -cells of Islets of Langerhans and stimulates glycogenolysis (3) Secretion of thymosins is stimulated with aging (4) If females, FSH first binds with specific receptors on ovarian cell membrane Ans. Amity Institute for Competitive Examinations : Phones: 24336143/44, 25573111/2/3/4, 95120-2431839/42 - 18 - Visit:MyCollegeBag.in Free Coaching for HC Verma , Last Year question Paper, Sample Papers. MyCollegeBag.in The Best Place for Free And Fare Education CBSE-2012 (Pre) Biology 121. Cymose inflorescence is present in (1) Brassica (2) Solanum (3) Sesbania (4) Trifolium Ans. 122. Which one of the following is correctly matched ? (1) Yeast – Zoospores (2) Onion – Bulb (3) Ginger – Sucker (4) Chlamydomonas – Conidia Ans. 123. What is true about ribosomes ? (1) These are self - splicing introns of some RNAs (2) The prokaryotic ribosomes are 80S, where “S” stands for sedimentation coefficient (3) These are composed of ribonucleic acid and proteins (4) These are found only in eukaryotic cells Ans. 124. A process that makes important difference between C3 and C4 plants is (1) Photorespiration (2) Transpiration (3) Glycolysis (4) Photosynthesis Ans. 125. Placentation in tomato and lemon is (1) Axile (2) Parietal (3) Free central (4) Marginal Ans. 126. If one strand of DNA has the nitrogenous base sequence as ATCTC, what would be the complementary RNA strand sequence ? (1) ATCGU (2) TTAGU (3) UAGAC (4) AACTG Ans. 127. Select the correct statement from the following regarding cell membrane (1) Fluid mosaic model of cell membrane was proposed by Singer and Nicolson (2) Na+ and K+ ions move across cell membrane by passive transport (3) Proteins make up 60 to 70% of the cell membrane (4) Lipids are arranged in a bilayer with polar heads towards the inner part Ans. 128. For transfomation, micro-particles coated with DNA to be bombarded with gene gun are made up of (1) Gold or Tungsten (2) Silver or Platinum (3) Platinum or Zinc (4) Silicon or Platinum Ans. 129. Which one is a true statement regarding DNA polymerase used in PCR ? (1) It remains active at hight temperature (2) It is used to ligate introduced DNA in recipient cells (3) It serves as a selectable marker (4) It is isolated from a virus Ans. 130. The upright pyramid of number is absent in (1) Grassland (2) Pond (3) Forest (4) Lake Ans. Amity Institute for Competitive Examinations : Phones: 24336143/44, 25573111/2/3/4, 95120-2431839/42 - 19 - Visit:MyCollegeBag.in Free Coaching for HC Verma , Last Year question Paper, Sample Papers. MyCollegeBag.in The Best Place for Free And Fare Education CBSE-2012 (Pre) Biology 131. Signals for parturition originate from (1) Fully developed foetus only (2) Both placenta as well as fully developed foetus (3) Oxytocin released from maternal pituitary (4) Placenta only Ans. 132. Given below is an imaginary pyramid of numbers. What could be one of the possibilities about certain organisms at some of the different levels ? TC 10 SC 50 PC 500 PP 1 (1) Level PC is “rats” and level SC is “cats” (2) Level PC is “insects” and level SC is “small insectivorous birds” (3) Level PP is “phytoplanktons” in sea and “Whale” on top level TC (4) Level one PP is “pipal trees” and the level SC is “sheep Ans. 133. The common bottle cork is a product of (1) Vascular Cambium (2) Dermatogen (3) Phellogen (4) Xylem Ans. 134. Nuclear membrane is absent in (1) Nostoc (2) Penicillium (3) Agaricus (4) Volvox Ans. 135. The cyanobacteria are also referred to as (1) Blue green algae (2) Protists (3) Golden algae (4) Slime moulds Ans. 136. Which one of the following microbes forms symbiotic association with plants and helps them in their nutrition ? (1) Trichoderma (2) Azotobacter (3) Aspergillus (4) Glomus Ans. 137. Which one of the following is not a functional unit of an exosystem ? (1) Stratification (2) Energy flow (3) Decomposition (4) Productivity Ans. 138. During gamete formation, the enzyme recombinase participates during (1) Prophase-II (2) Metaphase-I (3) Anaphase-II (4) Prophase-I Ans. Amity Institute for Competitive Examinations : Phones: 24336143/44, 25573111/2/3/4, 95120-2431839/42 - 20 - Visit:MyCollegeBag.in Free Coaching for HC Verma , Last Year question Paper, Sample Papers. MyCollegeBag.in The Best Place for Free And Fare Education CBSE-2012 (Pre) Biology 139. Anxiety and eating spicy food together in an otherwise normal human, may lead to (1) Vomiting (2) Indigestion (3) Jaundice (4) Diarrhoea Ans. 140. Removal of RNA polymerase III from nucleoplasm will affect the synthesis of (1) rRNA (2) tRNA (3) hnRNA (4) mRNA Ans. 141. In which one of the following, the genus name, its two characters and its phylum are not correctly matched, whereas the remaining three are correct ? Genus Phylum Two Characters Name (a) Jointed appendages (1) Periplaneta Arthropoda (b) Chitinous exoskeleton (a) Body segmented (2) Pila Mollusca (b) Mouth with radula (a) Spiny Skinned (3) Asterias (b) Water vascular Echinodermata system (a) Pore bearing (4) Sycon Porifera (b) Canal system Ans. 142. F2 generation in a Mendelian cross showed that both genotypic and phenotypic ratios are same as 1 : 2 : 1. It represents a case of (1) Monohybrid cross with incomplete dominance (2) Co-dominance (3) Dihybrid cross (4) Monohybrid cross with complete dominance Ans. 143. Select the correct statement from the ones given below with respect to Periplaneta americana (1) Grinding of food is carried out only by the mouth parts (2) Nervous system located dorsally, consists of segmentally arranged ganglia joined by a pair of longitudinal connectives (3) Males bear a pair of short thread like anal styles (4) There are 16 very long Malpighian tubules present at the junctions of midgut and hindgut Ans. 144. Cirrhosis of liver is caused by the chronic intake of (1) Cocaine (2) Opium (3) Alcohol (4) Tobacco (Chewing) Ans. Amity Institute for Competitive Examinations : Phones: 24336143/44, 25573111/2/3/4, 95120-2431839/42 - 21 - Visit:MyCollegeBag.in Free Coaching for HC Verma , Last Year question Paper, Sample Papers. MyCollegeBag.in The Best Place for Free And Fare Education CBSE-2012 (Pre) Biology 145. Monascus purpureus is a yeast used commercially in the production of (1) Blood cholesterol lowering statins (2) Ethanol (3) Streptokinase for removing clots from the blood vessels (4) Citric acid Ans. 146. The coconut water and the edible part of coconut are equivalent to (1) Embryo (2) Endosperm (3) Endocarp (4) Mesocarp Ans. 147. Companion cells are closely associated with (1) Guard cells (2) Sieve elements (3) Vessel elements (4) Trichomes Ans. 148. Given below is the diagrammatic representation of one of the categories of small molecular weight organic compounds in the living tissues. Identify the category shown and the one blank component “X” in it Category Component O "X" (1) Nucleoside Uracil HOCH2 (2) Cholesterol Guanin (3) Amino acid NH 2 (4) Nucleotide Adenine Ans. OH OH 149. Which one of the following is not a gaseous biogeochemical cycle in ecosystem ? (1) Carbon cycle (2) Sulphur cycle (3) Phosphorus cycle (4) Nitrogen cycle Ans. 150. Which one of the following is the correct statement for respiration in humans ? (1) About 90% of carbon dioxide (CO2) is carried by haemoglobin as carbamino-haemoglobin (2) Cigarette smoking may lead to inflammation of bronchi (3) Neural signals from pneumotoxic centre in pons region of brain can increase the duration of inspiration (4) Workers in grinding and stone-breaking industries may suffer, from lung fibrosis. Ans.  Amity Institute for Competitive Examinations : Phones: 24336143/44, 25573111/2/3/4, 95120-2431839/42 - 22 - Visit:MyCollegeBag.in Free Coaching for HC Verma , Last Year question Paper, Sample Papers. MyCollegeBag.in The Best Place for Free And Fare Education CBSE - 2012 (Pre) PHYSICS CODE – B 151. In a CE transistor amplifier, the audio signal voltage across the collector resistance of 2 k is 2V. If the base resistance is 1 k and the current amplification of the transistor is 100, the input signal voltage is (1) 10 mV (2) 0.1 V (3) 1.0 V (4) 1 mV 2 2  103 Sol:  100  Vi 103  Vi = 10 mV 152. A coil of resistance 400  is placed in a magnetic field. If the magnetic flux  (wb) linked with the coil varies with time t (sec) as  = 50 t2 + 4, the current in the coil at t = 2 sec is (1) 1 A (2) 0.5 A (3) 0.1 A (4) 2 A d Sol: |emf | =  100t dt at t = 2, emf = 200 V 200 i= = 0.5 A 400 153. Liquid oxygen at 50 K is heated to 300 K at constant pressure of 1 atm. The rate of heating is constant. Which one of the following graphs represents the variation of temperature with time? Temp. Temp. Temp. Temp. (1) (2) (3) (4) Time Time Time Time Sol: Factual 154. One mole of an ideal gas goes form an initial state A to final state B via two processes: It first undergoes isothermal expansion from volume V to 3V and then its volume is reduced from 3V to V at constant pressure. The correct P-V diagram representing the two processes is: (1) (2) (3) (4) Amity Institute for Competitive Examinations : Phones: 24336143/44, 25573111/2/3/4, 95120-2431839/42 - 23 - Visit:MyCollegeBag.in Free Coaching for HC Verma , Last Year question Paper, Sample Papers. MyCollegeBag.in The Best Place for Free And Fare Education CBSE-2012 (Pre) Physics Sol: Factual 155. A solid cylinder of mass 3 kg is rolling on a horizontal surface with velocity 4 ms–1. It collides with a horizontal spring of force constant 200 Nm–1. The maximum compression produced in the spring will be (1) 0.2 m (2) 0.5 m (3) 0.6 m (4) 0.7 m 2 1 1 (3  R 2 )  4  1 Sol:  3(4) 2       Kx2 2 2 2 R 2  x = 0.6 m 156. An electric dipole of moment ‘p’ is placed in an electric field of intensity ‘E’. The dipole acquires a position such that the axis of the dipole makes an angle  with the direction of the field. Assuming that the potential energy of the dipole to be zero when  = 90°, the torque and the potential energy of the dipole will respectively be (1) pE cos, – pE sin (2) pE sin, – pE cos (3) pE sin, – 2pE cos (4) pEsin, 2pEcos   Sol: Potential energy =  P.E 157. The horizontal range and the maximum height of a projectile are equal. The angle of projection of the projectile is 1 (1)  = 45° (2)   tan 1   (3)   tan 1 (4) (4)   tan 1 (2)  4 u 2 sin 2  2u 2 sin  cos  Sol:  2g g  tan  = 4  = tan–1 (4) 158. If the nuclear radius of 27Al is 3.6 Fermi, the approximate nuclear radius of 64Cu in Fermi is: (1) 3.6 (2) 2.4 (3) 1.2 (4) 4.8 Sol: R  A1/3 1/3  3.6   27  3       R = 4.8 F  R   64  4 159. Two similar coils of radius R are lying concentrically with their planes at right angles to each other. The currents flowing in them are I and 2I, respectively. The resultant magnetic field induction at the centre will be 0 I 5 0 I 3 0 I 0 I (1) (2) (3) (4) R 2R 2R 2R 2  0 I   0  2 I  5 0 I Sol: B =  2R   2R  = 2R     160. When a biconvex lens of glass having refractive index 1.47 is dipped in a liquid, it acts as a plane sheet of glass. This implies that the liquid must have refractive index (1) less than that of glass (2) equal to that of glass (3) less than one (4) greater than that of glass 1  2  1 1  Sol:    1    f  1  R 1 R 2  Amity Institute for Competitive Examinations : Phones: 24336143/44, 25573111/2/3/4, 95120-2431839/42 - 24 - Visit:MyCollegeBag.in Free Coaching for HC Verma , Last Year question Paper, Sample Papers. MyCollegeBag.in The Best Place for Free And Fare Education CBSE-2012 (Pre) Physics 161. Two ideal diodes are connected to a battery as shown in the circuit. The D1 current supplied by the battery is (1) 0.5 A (2) 0.75 A D2 (3) zero (4) 0.25 A Sol: D1 is forward bias while D2 is reverse bias 5V 5 i= = 0.5 A 10 162. Two spheres A and B of masses m1 and m2 respectively collide. A is at rest initially and B is moving with v velocity v along x-axis. After collision B has a velocity in a direction perpendicular to the original 2 direction. The mass A moves after collision in the direction (1)  = tan–1 (–½) to the x-axis (2) same as that of B (3) opposite to that of B (4)  = tan–1 (½) to the x-axis Sol: m1v1 cos  = m2v....(i) After collision v/2 m1v1 sin  = m2v/2....(ii) Before collision 1 1 B A Divide : (ii) by (i) tan  =  = tan–1 O.................  O B 2 2 v Rest v1 A     163. A particle has initial velocity (2i  3 j ) and acceleration (0.3i  0.2 j ). The magnitude of velocity after 10 seconds will be (1) 9 units (2) 92 units (3) 52 units (4) 5 units    Sol: v  u  at = (2iˆ  3 ˆj )  (0.3iˆ  0.2 ˆj )  10 = (5iˆ  5 ˆj )   | v | 5 2 units 164. The height which the weight of a body becomes 1/16th, its weight on the surface of earth (radius R) is (1) 4 R (2) 5 R (3) 15 R (4) 3 R g g Sol:  2 16  h  1    R  h  1   = 4 (h = 3R)  R 165. Four point charges –Q, –q, 2q and 2Q are placed, one at each corner of the square. The relation between Q and q for which the potential at the centre of the square is zero is 1 1 (1) Q (2) Q = – q (3) Q (4) Q = q q q Amity Institute for Competitive Examinations : Phones: 24336143/44, 25573111/2/3/4, 95120-2431839/42 - 25 - Visit:MyCollegeBag.in Free Coaching for HC Verma , Last Year question Paper, Sample Papers. MyCollegeBag.in The Best Place for Free And Fare Education CBSE-2012 (Pre) Physics k ( Q ) k (  q) k (2 q) k (2Q ) –Q –q Sol: O =    x x x x Q+q=0 2Q 2q  Q = –q 166. When a string is divided into three segments of length l1, l2 and l3, the fundamental frequencies of these three segments are v1, v2 and v3 respectively. The original fundamental frequency (v) of the string is 1 1 1 1 (1)    (2) v  v1  v2  v3 v v1 v2 v3 1 1 1 1 (3) v = v1 + v2 + v3 (4)    v v1 v2 v3 v Sol: v = 2l v v1 = 2l 1 v v2 = 2l 2 v v3 = 2l 3 1 1 1 1  vv v v 1 2 3 167. A ring is made of a wire having a resistance R0 = 12 . Find the points A and B, as shown in the figure, at which a current carrying conductor should be connected so that the resistance R of the sub circuit 8 between these points is equal to  l1 3 l1 1 l1 5 A B (1)  (2)  l2 2 l2 8 l1 1 l1 3 (3)  (4)  l2 3 l2 8 l2  A A  3 Sol:  l  l   8....(i)  1 2  (l1  l2 )  12.... (ii) A l1 1 Solving l  2 2 Amity Institute for Competitive Examinations : Phones: 24336143/44, 25573111/2/3/4, 95120-2431839/42 - 26 - Visit:MyCollegeBag.in Free Coaching for HC Verma , Last Year question Paper, Sample Papers. MyCollegeBag.in The Best Place for Free And Fare Education CBSE-2012 (Pre) Physics 168. A geostationary satellite is orbiting the earth at a height of 5R above the surface of the earth, R being the radius of the earth. The time period of another satellite in hours at a height of 2R from the surface of the earth is 6 (1) (2) 5 (3) 10 (4) 62 2 Sol:  T 2  r3 3/2  24   6 R       T   3R  24 =2 2 T T= 6 2    169. ABC is an equilateral triangle with O as its centre. F1 , F2 and F3 represent three forces acting along the sides AB, BC and AC respectively. If the  total torque about O is zero then the magnitude of F3 is (1) 2(F1 + F2) (2) F1 + F2 F1  F2 (3) F1 – F2 (4) A 2 F3 x x Sol: F2 × x – F3 × x + F1 × x = 0 x B F3 = F1 + F2 C F2 F1 170. If the radius of a star is R and it acts as a black body, what would be the temperature of the star, in which the rate of energy production is Q? 1/ 4 1/ 2  Q  Q  Q  1/ 4 (1)  2   4R   (2) 4R 2  (3)  2   4R   (4)  4R Q /   2 ( stands for Stefan’s constant) Sol: Q = 4R2T4 1/4  Q   T=  2   4R   171. When a mass is rotating in a plane about a fixed point, its angular momentum is directed along: (1) the tangent to the orbit (2) a line perpendicular to the plane of rotation (3) the line making an angle of 45° to the plane of rotation (4) the radius Sol: Factual Amity Institute for Competitive Examinations : Phones: 24336143/44, 25573111/2/3/4, 95120-2431839/42 - 27 - Visit:MyCollegeBag.in Free Coaching for HC Verma , Last Year question Paper, Sample Papers. MyCollegeBag.in The Best Place for Free And Fare Education CBSE-2012 (Pre) Physics 172. Two sources of sound placed close to each other, are emitting progressive waves given by y1 = 4 sin 600 t and y2 = 5 sin 608 t. An observer located near these two sources of sound will hear: (1) 4 beats per second with intensity ratio 81 : 1 between waxing and waning (2) 4 beats per second with intensity ratio 25 : 16 between waxing and waning (3) 8 beats per second with intensity ratio 25 : 16 between waxing and waning (4) 8 beats per second with intensity ratio 81 : 1 between waxing and waning I1 ( A1  A2 ) 2 81 Sol:   I 2 ( A1  A2 ) 2 1 Beat frequency = 304 – 300 = 4 Hz. 173. A car of mass 1000 kg negotiates a banked curve of radius 90 m on a frictionless road. If the banking angle is 45°, the speed of the car is (1) 10 ms–1 (2) 20 ms–1 (3) 30 ms–1 (4) 5 ms–1 v2 Sol: tan    v  90  10  tan 45º  30 m / sec rg 174. The magnifying power of a telescope is 9. When it is adjusted for parallel rays the distance between the objective and eyepiece is 20 cm. The focal length of lenses are (1) 11 cm, 9 cm (2) 10 cm, 10 cm (3) 15 cm, 5 cm (4) 18 cm, 2 cm Sol: f0 + fe = 20... (i) f0 a... (ii) fe Solving, f0 = 18 cm fe = 2 cm 175. What is the flux through a cube of side ‘a’ if a point charge of q is at one of its corner? q 2q q q (1) 6a 2 (2) (3) (4) 2 0 0 8 0 0 Sol: Application of Gauss’s theorem 176. An -particle moves in a circular path of radius 0.83 cm in the presence of a magnetic field of 0.25 Wb/m2. The de Broglie wavelength associated with the particle will be (1) 0.01 Å (2) 1 Å (3) 0.1 Å (4) 10 Å 2  P  Sol: 0.83  10   ... (i)  2eB  h  6.6  1034  13   2 19   9.94  10 m  0.01 Å p  0.83  10  2  1.6  10  0.25  Amity Institute for Competitive Examinations : Phones: 24336143/44, 25573111/2/3/4, 95120-2431839/42 - 28 - Visit:MyCollegeBag.in Free Coaching for HC Verma , Last Year question Paper, Sample Papers. MyCollegeBag.in The Best Place for Free And Fare Education CBSE-2012 (Pre) Physics 177. The figure shows a logic circuit with two inputs A and B and the output C. The voltage wave forms across A, B and C are as given. The logic circuit gate is A B C 0 t1 t2 t3 t4 t5 t6 (1) NAND gate (2) OR gate (3) NOR gate (4) AND gate Sol: A B C 0 0 0 1 0 1 0 1 1 1 1 1 or Gate 178. A compass needle which is allowed to move in a horizontal plane is taken to a geomagnetic pole. It: (1) will stay in east-west direction only (2) will become rigid showing no movement (3) will stay in any position (4) will stay in north-south direction only Sol: Magnetic field is vertical at poles. 179. A spherical planet has a mass Mp and diameter Dp. A particle of mass m falling freely near the surface of this planet will experience an acceleration due to gravity, equal to (1) 4 GMp m / Dp2 (2) 4GMp / Dp2 (3) GMp m/Dp2 (4) GMp / Dp2 GM P GM P 4GM P Sol: g 2  2  R ( DP /2 ) DP2 180. A 200 W sodium street lamp emits yellow light of wavelength 0.6 m. Assuming it to be 25% efficient in converting electrical energy to light, the number of photons of yellow light it emits per second is (1) 3 × 1019 (2) 1.5 × 1020 (3) 6 × 1018 (4) 62 × 1020 25 Sol: Energy emitted = 200   50 W  50 J / sec. 100 50  0.6  106 No. of photons = 34 8  1.5  1020 6.6  10  3  10 A B 181. The potential energy of a particle in a force field is: U   , where A and B are positive constants r2 r and r is the distance of particle from the centre of the field. For stable equilibrium the distance of the particle is (1) B/A (2) B/2A (3) 2A/B (4) A/B Amity Institute for Competitive Examinations : Phones: 24336143/44, 25573111/2/3/4, 95120-2431839/42 - 29 - Visit:MyCollegeBag.in Free Coaching for HC Verma , Last Year question Paper, Sample Papers. MyCollegeBag.in The Best Place for Free And Fare Education CBSE-2012 (Pre) Physics  dV   2 A  2 Sol: F      3   r  c  dr   r  2A  r B 182. An electrons of a stationary hydrogen atom passes from the fifth energy level to the ground level. The velocity that the atom acquired as a result of photon emission will be 24m 24h R 25h R 25 m (1) 25h R (2) 25 m (3) 24 m (4) 24 h R (m is the mass of the electron, R, Rydberg constant and h, Planck’s constant) E  Sol: Momentum of atom, P     C   P  E hcR  1  h  R  24   24h  R  Velocity of H2 atom =   = mc  mc 1  25   m  25    25 m  m       183. In the circuit shown the cells A and B have negligible resistances. For VA = 12V, R1 = 500  and R = 100  the galvanometer (G) shows no deflection. The value of VB is R1 G R VA VB (1) 6 V (2) 4 V (3) 2 V (4) 12 V 12 1 Sol: i   A 600 50 1 P.D. across, R = 100  = 100   2 volt 50 184. Monochromatic radiation emitted when electron on hydrogen atom jumps from first excited to the ground state irradiates a photosensitive material. The stopping potential is measured to be 3.57 V. The threshold frequency of the material is (1) 2.5 × 1015 Hz (2) 4 × 1015 Hz (3) 5 × 1015 Hz (4) 1.6 × 1015 Hz 19 19  1 34 Sol: 1.6  10  3.75  13.6  1.6  10 1    6.6  10 vTh  4 Solving, vTh = 1.6  1015 Hz 185. A mixture consists of two radioactive materials A1 and A2 with half lives of 20 s and 10 s respectively. Initially the mixture has 40 g of A1 and 160 g of A2. The amount of the two in the mixture will become equal after (1) 40 s (2) 60 s (3) 80 s (4) 20 s 40  20  10 Sol: 160  80  40  10 t = 40 sec. Amity Institute for Competitive Examinations : Phones: 24336143/44, 25573111/2/3/4, 95120-2431839/42 - 30 - Visit:MyCollegeBag.in Free Coaching for HC Verma , Last Year question Paper, Sample Papers. MyCollegeBag.in The Best Place for Free And Fare Education CBSE-2012 (Pre) Physics 186. If voltage across a bulb rated 220 Volt-100 Watt drops by 2.5% of its rated value, the percentage of the rated value by which the power would decrease is (1) 10% (2) 20% (3) 2.5% (4) 5% V2 Sol: P R P V 100  2  100  2  2.5  5% I II III P V 187. Transfer characteristics [output voltage(V0) vs input voltage (Vi)] V0 for a base biased transistor in CE configuration is as shown in the figure. For using transistor as a switch, it is used (1) in region I (2) in region III (3) both in region (I) and (III) (4) in region II Sol: Factual Vi 188. C and Si both have same lattice structure, having 4 bonding electrons in each. However, C is insulator where as Si is intrinsic semiconductor. This is because (1) The four bonding electrons in the case of C lie in the third orbit, whereas for Si they lie in the fourth orbit (2) In case of C the valance band is not completely filled at absolute zero temperature (3) In case of C the conduction band is partly filled even at absolute zero temperature (4) The four bonding electrons in the case of C lie in the second orbit, whereas in the case of Si they lie in the third Sol: Factual 189. Two persons of masses 55 kg and 65 kg respectively, are at the opposite ends of a boat. The length of the boat is 3.0 m and weighs 100 kg. The 55 kg man walks up to the 65 kg man and sits with him. If the boat is in still water the centre of mass of the system shifts by (1) 0.75 m (2) 3.0 m (3) 2.3 m (4) zero Sol: There is no external force. D C 190. A thermodynamic system is taken through the cycle ABCD 2P Pressure as shown in figure. Heat rejected by the gas during the cycle is P A B (1) P V (2) 2 PV (3) 4 PV (4) ½ PV V 3V Sol: W = –2PV Volume  Q = W + E  Q = –2PV 191. The motion of a particle along a straight line is described by equation: x = 8 + 12t – t3 where x is in metre and t in second. The retardation of the particle when its velocity becomes zero, is (1) 12 ms–2 (2) 24 ms–2 (3) zero (4) 6 ms–2 dv Sol: v   12  3t 2  0  t  2 sec. dt d2x a 2  6t  12 ms2 dt Amity Institute for Competitive Examinations : Phones: 24336143/44, 25573111/2/3/4, 95120-2431839/42 - 31 - Visit:MyCollegeBag.in Free Coaching for HC Verma

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