A ball of mass $200\,g$ rests on a vertical post of height $20\,m$. A bullet of mass $10\,g$, travelling in horizontal direction, hits the centre of the ball. After collision both travels independently. The ball hits the ground at a distance $30\,m$ and the bullet at a distance of $120\,m$ from the foot of the post. The value of initial velocity of the bullet will be $............m/s$ (if $\left.g =10 m / s ^2\right)$

What percentage of kinetic energy of a moving particle is transferred to a stationary particle when it strikes the stationary particle of $5$ times its mass? (Assume the collision to be head-on elastic collision)

The principle of conservation of linear momentum can be strictly applied during a collision between two particles provided the time of impact is

 A lorry and a car moving with the same $K.E.$  are brought to rest by applying the same retarding force, then

A block of mass $m$ is moving with a velocity $u$ on a smooth horizontal surface towards a wedge of same mass initially kept at rest. Wedge is free to move in any direction. Initially the block moves up the smooth incline plane of the wedge to a height $h$ and again moves down back to the horizontal plane. In this process the wedge gains a velocity equal to

A sphere strikes a wall and rebounds with coefficient of restitution $1/3$. If it rebounds with a velocity of $0.1\, m/sec$ at an angle of $60^o$ to the normal to the wall, the loss of kinetic energy is