Is a nuclear submarine engine is one of the most obvious application of the action-reaction principle?
Rocket is better A nuclear submarine engine is a steam engine. The propeller is a screw. Steam engines are OK examples of action-reaction, but it’s sometimes a bit hard to see both components. Another action-reaction example would be a kid in a wagon who pushes against something, maybe a garden planter. The wagon moves one direction and the planter falls over the other direction. Such an example makes it easy to see both the action and the reaction. BTW, the action is the push, while the reaction is the movement of the wagon.
