Final answer:
The action force is the paddle pushing against the water, and the reaction force is the water pushing back against the paddle, propelling the boat forward. Newton's Third Law of Motion explains this interaction, which doesn't cancel out because the forces act on different systems.
Step-by-step explanation:
The action and reaction forces refer to a pair of forces acting in opposite directions, as defined by Newton's Third Law of Motion. When a paddle pushes against water (the action), it causes the water to exert an equal and opposite force back onto the paddle (the reaction).
This interaction between the paddle and the water causes the boat to move forward. Similarly, when a rower uses their arms to row, they apply a force on the oars (the action) which then apply a force on the water.
The water then pushes back against the paddles with an equal but opposite force (the reaction), which propels the boat forward. This interaction does not involve significant frictional forces but rather the applied force and its reaction.
Additionally, it's crucial to recognize that while action-reaction forces are equal in magnitude and opposite in direction, they do not cancel out because they act on different systems. This concept explains why objects like boats are able to move, as seen with other examples such as rockets and cars being propelled forward by a thrust reaction force.