how momentum of bullet is equal to the momentum of gun
Answers
Conservation of momentum is the law that is held true when the gun is fired and a "kick" is felt. When a bullet is fired from a gun, total momentum before is zero since nothing is moving. After firing the bullet there is a momentum in the forward direction. The gun must therefore have the same magnitude of momentum but in the opposite direction so that they cancel each other out leaving the total momentum still equal to zero. For this reason the gun must have a recoil velocity after the bullet is fired (i.e. the gun 'jumps' backwards and a 'kick' is felt).
As the bullet is propelled through the barrel, it gains momentum. In order for the entire system of the gun and the ammunition to have equal momentum, the gun must gain momentum in the opposite direction from the bullet. Momentum is a vector quantity, having both a direction and a direction. The faster an object is moving or the more mass it has, the more momentum it has in the direction of its motion (momentum = mass velocity). Because momentum is a conserved quantity, it cannot be created or destroyed (momentum before = momentum after). It can only be transferred between objects. Momentum is conserved because of Newton's third law of motion.