A shell is fired from a cannon with velocity v m/sec at an angle 0 with the horizontal direction' At the highest point it its path it explodes into two pieces of equal mass. One of the pieces retraces its path to the cannon and the speed in m/sec of the other piece immediately after the explosion is
As the shell is at the highest point, hence the velocity of the shell before explosion must be entirely horizontal i.e. v cos Now when the explosion takes place, the total momentum before and after the collision must be the same( explosion consists of only internal forces). The piece which retraces its path to the cannon has velocity -v cos immediately after collision.Let P2 be the momentum of second particle, then