You are on a frictionless horizontal plane. How can you get off if no horizontal force is exerted by pushing against the surface?

$A$ man (mass $= 50\, kg$) and his son (mass $= 20\, kg$) are standing on a frictionless surface facing each other. The man pushes his son so that he starts moving at a speed of $0.70\, ms^{-1}$ with respect to the man. The speed of the man with respect to the surface is ........ $ms^{-1}$

$A$ bomb is projected upwards. At its topmost point,it explodes into three identical fragments. The first fragment reaches the ground in $10 \ s$,and the other two reach the ground in $20 \ s$ each. Find the maximum height $h$ reached by the original bomb. (in $m$)

$A$ bomb at rest explodes into three pieces of equal masses. If two pieces move perpendicular to each other,each with a speed $v$,then the speed of the third piece is:

$A$ bullet is fired from a gun. If the gun recoils freely,the kinetic energy of the gun will be

$A$ shell,in flight,explodes into four unequal parts. Which of the following is conserved?