Physics
posted by Sandhu .
A 12.0 kg shell is launched at an angle of 55 degrees above the horizon with an initial velocity of 150 m/s. When at its highest point, the shell explodes into 2 fragments  1 fragments is 3 times heavier than the other. The 2 fragments reach the ground at the same time, ignore air resistance. If the heavier fragment lands back at the same point from which the shell was launched, where will the 2nd fragment land and how much energy was released by the explosion?

consider the explosion. You know momentum before, so the sum of the momentum after must equal that. That means the heavier fragment had exactly equal and opposite the veloity of the shell just before explosion, then that leaves the other fragement momentum. Some tricky algebra will be required.

I have the same problem and I can't figure it out the answers on these forums are useless