System of Particles and Rotational Motion Questions And Answers.

1.A gun fires a bullet of mass 50g with a velocity of 30m/s. Because of this, the gun is pushed back with a velocity of 1m/s. The mass of the gun is?
A. 5.5kg
B. 3.5kg
C. 1.5kg
D. 0.5kg

2.A body of mass 5kg is raised vertically to a eight of 10m by a force of 170N. The velocity of the body at this height will be?
A. 37m/s
B. 22m/s
C. 15m/s
D. 9.8m/s

3.A position dependent force, F = 7-2x+3x2-N acts on a small body of mass 2kg and displaces it from x = 0 to x = 5m. The work done in joules is
A. 135
B. 270
C. 35
D. 70

4.A particle of mass M is moving in a horizontal circle of radius R with uniform speed v. When it moves from one point to a diametrically opposite point, its?
A. Kinetic energy changes by (Mv)2/4
B. Momentum does not change
C. Momentum changes by 2Mv
D. Kinetic energy changes by (Mv)2

5.Two identical balls A and B collide head on elastically. If velocities of A and B, before the collision are +0.5m/s and -0.3m/s respectively, then the velocities after the collision, are?
A. -0.5m/s and +0.3m/s
B. +0.5m/s and +0.3m/s
C. +0.3m/s and -0.5m/s
D. -0.3m/s and +0.5m/s