Jet propulsion

Jet propulsion is a fun way for things to move. It works by shooting out a stream of air or water in the opposite direction. When something pushes on another thing, that other thing pushes back with an equal force. This idea is called Newton's third law.

Many machines use jet propulsion. Jet engines power airplanes, helping them fly high in the sky. In the water, pump-jets help boats and ships move quickly. Rockets and special space engines also use jet propulsion to travel through space.

Some sea animals use jet propulsion to move too. Octopuses and salps, which are tiny sea creatures, can squirt water out of their bodies to zoom away quickly. The flying squid can use jet propulsion underwater and also in the air when it jumps out of the water.

Jet propulsion helps both machines and animals move fast and efficiently. It’s a clever trick used all around us, from the sky to the deep blue sea.