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 :

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 body of mass $5 \,kg$  explodes at rest into three fragments with masses in the ratio $1 : 1 : 3$. The fragments with equal masses fly in mutually perpendicular directions with speeds of $21 \,m/s$. The velocity of the heaviest fragment will be

$A$ system of $N$ particles is free from any external forces. Which of the following is true for the magnitude of the total momentum of the system?

A shell at rest at the origin explodes into three fragments of masses $1\ kg$ , $2\ kg$ and $m\ kg$ . The $1\ kg$ and $2\ kg$ pieces fly off with speeds of $5\ ms^{-1}$ along $x-axis$ and $6\ ms^{-1}$ along $y-axis$ respectively. If the $m\, kg$ piece flies off with a speed of $6.5\ ms^{-1}$ , the total mass of the shell must be    ......... $kg$

A bullet mass $10\, gm$ is fired from a gun of mass $1\,kg$. If the recoil velocity is $5\, m/s$, the velocity of the muzzle is ........ $m/s$