Question
A body at rest explodes in three fragments. What is the velocity of the centre of mass of exploded part?
Solution
Zero.
In the absence of external force, the centre of mass moves with constant velocity. Since before explosion the body was at rest, therefore, the velocity of the centre of mass is zero before an explosion. Hence it will also be zero after the explosion.
In the absence of external force, the centre of mass moves with constant velocity. Since before explosion the body was at rest, therefore, the velocity of the centre of mass is zero before an explosion. Hence it will also be zero after the explosion.
