If a man increase his speed by $2 \,m/s$ , his K.E. is doubled, the original speed of the man is

A car accelerates from rest to $u\,m / s$. The energy spent in this process is $E\,J$. The energy required to accelerate the car from $u\,m / s$ to $2u\,m / s$ is $nE\,J$. The value of $n$ is ..............

Two solids $A$ and $B$ of mass $1\, kg$ and $2\, kg$ respectively are moving with equal linear momentum. The ratio of their kinetic energies $(K.E.)_{ A }:( K.E. )_{ B }$ will be $\frac{ A }{1},$ so the value of $A$ will be ..... .

If kinetic energy of a body is increased by $300\%$ than percentage change in momentum will be

A wooden block of mass $M$  is suspended by a cord and is at rest. A bullet of mass $m,$ moving with a velocity $v$ passes through the block and comes out with a velocity $v/2$  in the same direction. If there is no loss in kinetic energy, then upto what height the block will rise

A particle of mass $0.1 \,kg$ is subjected to a force which varies with distance as shown. If it starts its journey from rest at $x=0$, then its velocity at $x=12 \,m$ is .............. $m / s$