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Phycology is the study of

(a) Algae (b) Fungi (c) Bacteria (d) All the above Ans. a (47)

1. Who is regarded as the “Father of Indian Phycology”

(a) Prof. M.O.P. Iyenger (b) Prof. J.N. Mishra (c) Prof. R.R. Mishra (d) Prof. R.N. Singh Ans. a (9)

65. A wire extends by 1 mm when a force is applied. Double the force is applied to another wire of same material and length but half the radius of cross-section. The elongation of the wire in mm will be

(a) 8 (b) 4 (c) 2 (d) 1 Answer-a (10)

Which one of the following sets forms the biodegradable polymer

Ans. b (15)

Escape velocity on the earth

(a) Is less than that on the moon (b) Depends upon the mass of the body (c) Depends upon the direction of projection (d) Depends upon the height from which it is projected Answer: d (5)

Buna – S is a polymer of

a. Butadiene only b. Butadiene and styrene c. Sturene only d. Butadiene nitryl Ans. b (15)

On complete hydrogenation, natural rubber produces

a. Ethylene- propylene copolymer b. Vulcanised rubber c. Polypropylene d. Polybutylene Ans. a (6)

Ebonite is

a. Polropene b. Natural rubber c. Synthetic rubber d. Highly vulcanized rubber Ans. d (7)

Which of the following statement is correct regarding the drawbacks of raw rubber

a. It is plastic in nature b. It has little durability c. It has large water-absorption capacity d. All of these Ans. d (8)

What is the percentage of sulphur used in vulcanization of rubber

a. 05% b. 03% c. 30% d. 55.0% Ans. a (7)

Natural rubber has

a. All cis- configuration b. All trans-configuration c. Alternate cis – and trans-configuration d. Random cis-and trans-configuration Ans. a (8)

Buna – N synthetic rubber is a copolymer of

Ans. c (10)

Which of the following is used in vulcanization of rubber

a. SF6 b. CF4 c. Cl2 F2 d. C2 F2 Ans. a (14)

The synthetic polymer which resembles natural rubber is

a. Neoprene b. Chloroprene c. Glyptal d. Nylon Ans. a (8)

The monomer of natural polymer rubber is

a. Neoprene b. Isoprene c. Chloroprene d. Butadiene Ans. b (7)

Heating of rubber with sulphur is known as

a. Galvanisation b. Vulcanisation c. Bessemerisation d. Sulphonation Ans. b (11)

151. A uniform solid cylinder of mass M and radius R rotates about a frictionless horizontal axle. Two similar masses suspended with the help two ropes wrapped around the cylinder. If the system is released from rest then the acceleration of each mass will be

(a) 4mg/M+2m (b) 4mg/M+4m (c) 2mg/M+m (d) 2mg/M+2m Ans. b (19)

150. A cylinder of mass M and radius r is mounted on a frictionless axle over a well. A rope of negligible mass is wrapped around the cylinder and a bucket of mass m is suspended from the rope. The linear acceleration of the bucket will be

(a) Mg/M+2m (b) 2Mg/m+2M (c) Mg/2M+m (d) 2mg/M+2m Ans. d (82)

149. A massless string is wrapped round a disc of mass M and radius R. Another end is tied to a mass m which is initially at height h from ground level as shown in the fig. If the mass is released then its velocity while touching the ground level will be

(a) √(2gh) (b) √(2gh)M/m (c) √(2ghm/M) (d) √(4mgh/2m+M) Ans. d (63)

148. A uniform disc of radius R and mass M can rotate on a smooth axis passing through its centre and perpendicular to its plane. A force F is applied on its rim. See fig. What is the tangential acceleration

(a) 2F/M (b) F/M (c) F/2M (d) F/4M Ans. a (34)

The escape velocity of a rocket launched from the surface of the earth

(a) Does not depend on the mass of the rocket (b) Does not depend on the mass of the earth (c) Depends on the mass of the planet towards which it is moving (d) Depends on the mass of the …

If acceleration due to gravity on the surface of a planet is two times that on surface of earth and its radius is double that of earth. Then escape velocity from the surface of that planet in comparison to earth will be

(a) 2 ve (b) 3 ve (c) 4 ve (d) None of these Answer: a (6)

Neoprene (Synethetic Rubber) is a polymer of

a. propene b. Vinyl chloride c. Chloroprene d. Butadiene Ans.c (5)

If the radius of a planet is R and its density is p , the escape velocity from its surface will be

(a) ve ∝ pR (b) ve ∝√pR (c) ve ∝ (√p/R) (d) ve ∝ (1/√pR) Answer: b (4)

Escape velocity on earth is 11.2 km/s. What would be the escape velocity on a planet whose mass is 1000 times and radius is 10 times that of earth

(a) 112 km/s (b) 11.2 km/s (c) 1.12 km/s (d) 3.7 km/s Answer: a (4)

57. A wire of length L and radius r is rigidly fixed at one end. On stretching the other end of the wire with a force F, the increase in its length is l. If another wire of same material but of length 2L and radius 2r is stretched with a force of 2F, the increase in its length will be

(a) l (b) 2l (c) l /2 (d) l /4 Answer-a (12)

56. Liquids have no Poisson’s ratio, because

(a) It has no definite shape (b) It has greater volume (c) It has lesser density than solid (d) None of the above Answer-a (3)

The angular velocity of rotation of star (of mass M and radius R) at which the matter start to escape from its equator will be

Answer: c (1)

55. If Young’s modulus for a material is zero, then the state of material should be

(a) Solid (b) Solid but powder (c) Gas (d) None of the above …

54. The elastic limit for a gas

(a) Exists (b) Exists only at absolute zero (c) Exists for a perfect gas (d) Does not exist Answer-a (20)

52. If the density of the material increases, the value of Young’s modulus

(a) Increases (b) Decreases (c) First increases then decreases (d) First decreases then increases Answer-a (18)

51. The longitudinal strain is only possible in

(a) Gases (b) Fluids (c) Solids (d) Liquids Answer-c (11)

49.The quality of the material which opposes the change in shape, volume or length is called

(a) Intermolecular repulsion (b) Intermolecular behaviour (c) Viscosity (d) Elasticity Answer-d (8)

Given mass of the moon is 1/81 of the mass of the earth and corresponding radius is 1/4 of the earth. If escape velocity on the earth surface is 11.2 km/s, the value of same on the surface of the moon is

(a) 0.14 km/s (b) 0.5 km/s (c) 2.5 km/s (d) 5 km/s Answer: c (4)

47. When compared with solids and liquids, the gases have

(a) Minimum volume elasticity (b) Maximum volume elasticity (c) Maximum Young’s modulus (d) Maximum modulus of rigidity Answer-a (13)

The escape velocity of a body on the surface of the earth is 11.2 km/s. If the earth’s mass increases to twice its present value and the radius of the earth becomes half, the escape velocity would become

(a) 5.6 km/s (b) 11.2 km/s (remain unchanged) (c) 22.4 km/s (d) 44.8 km/s Answer: c (5)

The escape velocity on earth is 11.2 km/s. On another planet having twice radius and 8 times mass of the earth, the escape velocity will be

(a) 3.7 km/s (b) 11.2 km/s (c) 22.4 km/s (d) 43.2 km/s Answer: c (5)

45. In suspended type moving coil galvanometer, quartz suspension is used because

(a) It is good conductor of electricity (b) Elastic after effects are negligible (c) Young’s modulus is greater (d) There is no elastic limit Answer-b (12)