Rocket engineers use newton's third law during launch. identify the action force.

A. exhaust gases push down on the earth

B. rocket travels upward

C. earth pushes back on the exhaust gases

The answer is A. Newton's third law of motion states that for every action, there is an equal and opposite reaction. A rocket exerts a large force on the gas that is in the rocket chamber (action). The gas thus exerts a large reaction force forward on the rocket (reaction). The large reaction force is called thrust.