question_answer

  A bullet of mass 0.02 kg is fired from a gun weighing 7.5 kg. If the initial velocity of the bullet is 200 m/s, calculate the speed with which the gun recoils.

Answer:

                  Here, the mass of the bullet, Mass of gun,     Velocity of bullet, and the speed of gun,                                                        (1) According to law of conservation of momentum, Total momentum of system after firing = Total momentum of system before firing i.e.,                               (1) (Since initial velocities of gun and bullet before firing is zero.) or or            or               or                                            (1)