A car is moving with velocity $V$. If stop after applying break at a distance of $20\; m$. If velocity of car is doubled, then how much distance it will cover (travel) after applying break

A bullet fired into a fixed target loses half of its velocity after penetrating $3\,cm$. How much further it will penetrate before coming to rest assuming that it faces constant resistance to motion?........$cm$

An engine of a train, moving with uniform acceleration, passes the signal-post with velocity $u$ and the last compartment with velocity $v$. The velocity with which middle point of the train passes the signal post is

A metro train starts from rest and in five seconds achieves $108\, km/h$. After that it moves with constant velocity and comes to rest after travelling $45\, m$ with uniform retardation. If total distance travelled is $395\,m$, then total time of travelling is.......$sec$

The velocity acquired by a body moving with uniform acceleration is $30\,ms ^{-1}$ in $2$ seconds and $60\,ms ^{-1}$ in four seconds. The initial velocity is $.............\frac{m}{s}$