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Question Bank No: 3

1. Which of the following does not affect the maximum height attained by projectile?

a)		Acceleration of the projectile
b)		Magnitude of initial velocity
c)		Mass of Projectile
d)		Angle of Projection

2. Which of the following is a self adjustment force?

a)		Static in friction
b)		Limiting Friction
c)		Dynamic Friction
d)		Sliding Friction

3. A toy of mass 1 kg is placed on a spring balance. Suddenly the toy jumps upwards. When it happens the reading of the spring balance changes from 1 kg to 1.10 kg. What will be the maximum value of the upward acceleration of the toy? Take $g = 10 {ms}^{2}$

a)		$1 {ms}^{- 2}$
b)		$0.1 {ms}^{- 2}$
c)		0.0 $1 {ms}^{- 2}$
d)		$0.001 {ms}^{- 2}$

4. The rotational KE of two bodies of moments of inertia $9 kg m^{2}$ and $1 kg m^{2}$ are the same. The ratio of their angular momenta is

a)		1:2
b)		1:3
c)		1:9
d)		3:1

5. A carnot engine whose whose sink is at 300K has an efficiency of 40%. By how much should the temperature of source be increased so as to increase its efficiency by 50% of original efficiency?

a)		250K
b)		275K
c)		325K
d)		380K

6. The potential gradiant along the length uniform wire is 10 v/m. The length of wire is 1m. What is the p.d across two points on the wire seperated by 25cm?

a)		2.5V
b)		5V
c)		7.5V
d)		10V

7. A 1000 kg lift is supported by a cable that can support 2000kg. The shortest distance in which the lift can be supported when it is descending with a speed of 2.5 m/s is ( $g = 10 m / s^{2})$

a)		5/16m
b)		5/32 m
c)		1m
d)		2m

8. Consider a car moving along a straight horizontal road with a speed of 72km/h. If the coefficient of static friction between road and tyres is 0.5, the shortest distance in which the car can be stopped is

a)		30m
b)		40m
c)		72m
d)		20m

9. Earth radius is R and acceleration due to gravity at its surface is g. If a body of mass m falls from a height h = R/5 from earth surface, its potential energy decreases by

a)		mgh
b)		4/5 mgh
c)		5/6 mgh
d)		6/7 mgh

10. If kinetic energy of a body increases by 0.1%. The percent increase in its momentum will be

a)		0.05%
b)		0.1%
c)		1%
d)		10%

11. Fast neutrons can easily be slowed down by

a)		the use of lead shield
b)		passing them through water
c)		elastic collision with heavy nuclei
d)		applying a strong electric field

12. A ball is dropped from height 10m. It is embedded in sand 1 meter and stops

a)		only momentum remains conserved
b)		only kinetic energy remains conserved
c)		both momentum and kinetic energy are conserved
d)		neither momentum nor kinetic energy conserved

13. In which case does the potential energy decrease

a)		on compressing the spring
b)		on stretching a spring
c)		on moving a body against gravitational pull
d)		on the rising of an air bubble in water

14. The kinetic energy of body of mass 2kg and momentum 2Ns is

a)		1J
b)		2J
c)		3J
d)		4J