In a spring gun having spring constant $100\, {N} / {m}$ a small ball $'B'$ of mass $100\, {g}$ is put in its barrel (as shown in figure) by compressing the spring through $0.05\, {m}$. There should be a box placed at a distance $'d'$ on the ground so that the ball falls in it. If the ball leaves the gun horizontally at a height of $2\, {m}$ above the ground. The value of $d$ is $….{m} .$ $\left(g=10\, {m} / {s}^{2}\right)$

The potential energy of a long spring when stretched by $2\,cm$ is $U$. If the spring is stretched by $8\,cm$, potential energy stored in it will be $…….\,U$

Two bodies $A$ and $B$ of masses $m$ and $2m$ respectively are placed on a smooth floor. They are connected by a spring. A third body $C$ of mass $m$ moves with velocity $V_0$ along the line joining $A$ and $B$ and collides elastically with $A$ as shown in fig. At a certain instant of time $t_0$ after collision, it is found that instantaneous velocities of $A$ and $B$ are the same. Further at this instant the compression of the spring is found to be $x_0$. Determine the spring constant

A ball of mass $m_1$ falls from height $h_1$ from rest to strike a spring of force constant $K$, which forces another ball of mass $m_2$ to jump on a horizontal floor at a height $h_2$ below from it. Find the horizontal distance at which ball of mass $m_2$ strikes from the position of start :- [Spring does not move]

A spring block system is placed on a rough horizontal floor. The block is pulled towards right to give spring some elongation and released.