UPSC Physics- Laws of Motion, Force, Work, Energy and Power, Centre of Mass

Ball bearings are used in bicycles, cars, etc., because 

In cricket match, while catching a fast moving ball, a fielder in the ground gradually pulls his hands backwards with the moving ball to reduce the velocity to zero. The act represents 

Statement A: Pulling a lawn roller is easier than pushing it.
Statement B: Pushing increases the apparent weight and hence the force of friction.

It is difficult to cut things with a blunt knife because

Statement A: When a gun is fired it recoils, i.e., it pushes back, with much less velocity than the velocity of the bullet.
Statement B: Velocity of the recoiling gun is less because the gun is much heavier than the bullet.

Two teams are pulling a rope with equal and opposite forces each of 5 kN in a tug of war so that a condition of equilibrium exists. What will be the tensile force in the rope?

Column-I
A. Rocket propulsion P. Force
B. Agent which causes Acceleration Q. Momentum
C. Product of mass and Velocity R. S.I. unit of force
D. Newton S. Law of Conservation momentum

Statement A: While walking on ice, one should take small steps to avoid slipping.
Statement B: This is because smaller steps ensure smaller friction.

Thomas and Mary are playing carom board. They arrange the seeds in the vertical order. Thomas strikes on the seeds with the striker, with a great speed. He finds that, the stakes do not fall down. On the other hand, when he strikes the seeds with less speed, all the seeds of the stakes fell down. Which property of force this shows?

A man getting down a running bus, falls forward because.