A shell of mass 200 g is fired by a gun of mass 100 kg. If the muzzle speed of the shell is 80 ms-1, then the recoil speed of the gun is

Here,Mass of the shell, m = 200g = 200 ×10-3 kgMass of the gun, M = 100 kgMuzzle speed of the shell, V = 80 ms-1Recoil speed of the gun, v = ?According to the principle of conservation of linear momentum,mV + Mv = 0v = mVM = -(200 × 10-3kg)(80 ms-1)100 kg= -16 × 10-2 ms-1 = -16 cm s-1-ve sign shows that the recoil speed of the gun will be in a direction opposite to that of the shell.