Equal force $F ( > mg)$ is applied to string in all the $3$ cases. Starting from rest, the point of application of force moves a distance of $2 m$ down in all cases. In which case the block has maximum kinetic energy?

$A$ block of mass $m$ is hung vertically from an elastic thread of force constant $mg/a$. Initially the thread was at its natural length and the block is allowed to fall freely. The kinetic energy of the block when it passes through the equilibrium position will be :

A bomb of mass $30\,kg$at rest explodes into two pieces of masses $18\,kg$ and $12\,kg$. The velocity of $18\,kg$ mass is $6\,m{s^{ - 1}}$. The kinetic energy of the other mass is ....... $J$

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

If momentum is increased by $20\%$ , then K.E. increases by ........... $\%$

A particle of mass $m_1$ is moving with a velocity $v_1$ and another particle of mass $m_2$ is moving with a velocity $v_2$ . Both of them have the same momentum but their different kinetic energies are $E_1$ and $E_2$ respectively. If $m_1 > m_2$ then