Question

On which laws is the principle of rocket propulsion based?

Answer 1

Newton's third law of motion

1. According to Newton's third law of motion, there is always an equal and opposite reaction to every action.
2. Furthermore, the action and reaction take place in two separate bodies. When two bodies collide, they exchange force that is of equal magnitude but acts in opposite directions.

Principle of rocket propulsion

1. The propulsion system's purpose is to generate thrust. Thrust is the force that moves a rocket through the air and through space. The rocket's engine pushes the rocket upward by releasing hot burning fuel in a downward direction, while the gases exert an equal and opposite force.
2. The conservation of momentum principle states that when two bodies contact, their momentum before and after the collision remains constant.
3. The momentum of the rocket and the gases is zero when it is stationary. The momentum of the rocket and the gases are equal and opposing after the fuel is ignited. As a result, the overall momentum is nil. Therefore, the principle is met.

Hence, the principle of rocket propulsion is based on newton's third law of motion.