Laws of Motion ...

When a bullet is fired at a target, its velocity decreases by half after penetrating 30 cm into it. The additional thickness it will penetrate before corning to rest is

If a person with a spring balance and a body hanging from it goes up and up in an aeroplane, then the reading of the weight of the body as indicated by the spring balance will

The time period of a simple pendulum measured inside a stationary lift isfound to be T. If the lift starts accelerating upwards with an acceleration g/3, the time period is

A ball of mass 400 gm is dropped from a height of 5 m. A boy on the ground hits the ball vertically upwards with a bat with an average force of 100 newton so that it attains a vertical height of 20 m. The time for which the ball remains in contact with the bat is [g = 10 m/s²]

The linear momentum p of a body moving in one dimension varies with time according to the equation p = a + bt², where a and b are positive constants. The net force acting on the body is

A body is imparted motion from rest to move in a straight line. If it is then obstructed by an opposite force, then

A second\'s pendulum is mounted in a rocket. Its period of oscillation decreases when the rocket

n small balls each of mass m impinge elastically each second on a surface with velocity u. The force experienced by the surface will be

A ball of mass 0.5 kg moving with a velocity of 2 m/s strikes a wall normally and bounces back with the same speed. If the time of contact between the ball and the wall is one millisecond, the average force exerted by the wall on the ball is