If a body looses half of its velocity on penetrating $3 \,cm$ in a wooden block, then how much will it penetrate more before coming to rest ........... $cm$

If the coefficient of restitution be $0.5,$ what is the percentage loss of energy on each rebounding of a ball dropped from a height ............ $\%$

If a body of mass $200\, g$ falls from a height $200 \,m$ and its total $P.E.$ is converted into $K.E.$ at the point of contact of the body with earth surface, then what is the decrease in $P.E.$ of the body at the contact $(g = 10\,m/{s^2})$ ............ $\mathrm{J}$

A ball of mass $2\,kg$ and another of mass $4\,kg$ are dropped together from a $60$ feet tall building. After a fall of $30$ feet each towards earth, their respective kinetic energies will be in the ratio of

A stationary particle explodes into two particles of a masses $m_1$ and $m_2$ which move in opposite directions with velocities ${v_1}$ and ${v_2}.$ The ratio of their kinetic energies ${E_1}/{E_2}$ is

Two masses of $1 \,gm$ and $4 \,gm$ are moving with equal kinetic energies. The ratio of the magnitudes of their linear momenta is