A bullet emerges from a barrel of length 1.2m with a speed of  640 m/s. Assuming constant acceleration, the approximate time that it spends in the barrel after the gun is fired is……….ms

Given  s=1.2 m           v=640 m/s            u=0From equation  v2−u2=2as                     640×640=2a×1.2                    a=64×64×1022.4 =8×64×1033From equation  v=u+at                        t=va=640×38×64×103=38×10−2=0.375×10−2=3.75ms