Question

Since the force that acts on a bullet when a gun is fired is equal and opposite to the force that acts on the gun, doesn't this imply a zero net force, and therefore the impossibility of an accelerating bullet?

Answer 1

When a gun is fired, the bullet is accelerated down the barrel by the force exerted by the hot gases produced by the combustion of gunpowder. According to Newton's third law of motion, the gun experiences an equal and opposite reaction force. However, the gun's mass is much greater than the bullet's, so the acceleration of the gun is negligible compared to the acceleration of the bullet.

Step-by-step explanation:

According to Newton's third law of motion, for every action, there is an equal and opposite reaction. When a gun is fired, the bullet is accelerated down the barrel by the force exerted by the hot gases produced by the combustion of gunpowder. This force is the action force. As a result of Newton's third law, the gun experiences a reaction force in the opposite direction. However, the gun is much more massive than the bullet, so the acceleration of the gun is negligible compared to the acceleration of the bullet.

Therefore, the statement that the force on the bullet is equal and opposite to the force on the gun does not imply a zero net force. The bullet can accelerate because the force acting on it is greater than the force acting on the gun due to their different masses.