$A$ bomb of mass $16 \ kg$ at rest explodes into two pieces of masses $4 \ kg$ and $12 \ kg.$ The velocity of the $12 \ kg$ mass is $4 \ m s^{-1}.$ The kinetic energy of the other mass is .............. $J$.

State and explain the law of conservation of momentum for a system of particles.

Newton's third law of motion leads to the law of conservation of

$A$ projectile moving vertically upwards with a velocity of $200\, ms^{-1}$ breaks into two equal parts at a height of $490\, m$. One part starts moving vertically upwards with a velocity of $400\, ms^{-1}$. How much time will it take,after the break up,for the other part to hit the ground? .............. $s$

$A$ bomb initially at rest explodes by itself into three equal mass fragments. The velocities of two fragments are $(1\hat{i}+3\hat{j}) \ m/s$ and $(2\hat{i}-4\hat{j}) \ m/s$. The velocity of the third fragment (in $m/s$) is

$A$ $1 \; kg$ stationary bomb explodes into three parts having mass ratio $1:1:3$. The parts with equal mass move in perpendicular directions with a velocity of $30 \; m/s$. What is the velocity of the third (heavier) part?