A gun of mass 20 kg has bullet of mass 0.1 kg in it. The gun is free to recoil 804 J of recoil energy are released on firing the gun. The speed of bullet (ms-1) is

Here, m1=20kg         m2=0.1kgwhere, v1 = velocity of recoil of gunand      v2 = velocity of bullet.As,        m1v1=m2v2           (∵momentum is conserved)                         v1=m2m1v2=0.120v2=v2200Recoil energy of gun =12m1v12=12×20v22002                                    804=10v224×104=v224×103                                    v2=804×4×103ms−1