A shell of mass $0.020\; kg$ is fired by a gun of mass $100\; kg$. If the muzzle speed of the shell is $80 \;m s^{-1}$, what is the recoil speed in $m/s$ of the gun ?

Particle $A$ of mass $m _{1}$ moving with velocity $(\sqrt{3} \hat{i}+\hat{j})\, ms ^{-1}$ collides with another particle $B$ of mass $m _{2}$ which is at rest initially. Let $\overrightarrow{ V }_{1}$ and $\overrightarrow{ V }_{2}$ be the velocities of particles $A$ and $B$ after collision respectively. If $m _{1}=2\, m _{2}$ and after collision $\overrightarrow{ V }_{1}=(\hat{ i }+\sqrt{3} \hat{ j })\, ms ^{-1},$ the angle between $\overrightarrow{ V }_{1}$ and $\overrightarrow{ V }_{2}$ is$......^o$

A ball is moving towards the wall as shown in diagram then its momentum is conserved

Two bodies of mass $4 \mathrm{~g}$ and $25 \mathrm{~g}$ are moving with equal kinetic energies. The ratio of magnitude of their linear momentum is :

A projectile is fired with velocity $u$ at an angle $\theta$ with horizontal. At the highest point of its trajectory it splits up into three segments of masses $m, m$ and $2 \,m$. First part falls vertically downward with zero initial velocity and second part returns via same path to the point of projection. The velocity of third part of mass $2 \,m$ just after explosion will be

A $1 \;kg$ stationary bomb is exploded in three parts having mass $1: 1: 3$ respectively. Parts having same mass move in perpendicular direction with velocity $30\; ms ^{-1}$, then the velocity of bigger part will be