Which term refers to equal and opposite forces exerted in response to applied forces?

The term that refers to equal and opposite forces exerted in response to applied forces is known as reaction forces. This concept is rooted in Newton's third law of motion, which states that for every action, there is an equal and opposite reaction. When one object exerts a force on a second object, the second object exerts a force of equal magnitude but in the opposite direction back on the first object. This interaction is crucial in understanding how objects behave when forces are applied and is fundamental in various applications, ranging from everyday situations, like walking, to complex engineering and physical systems.

The other terms provided pertain to different aspects of force interplay. Action forces typically refer to the initial forces that cause a change in the motion of an object, but they do not emphasize the necessary counteracting force. Forces of friction specifically relate to the resistance that one surface or object encounters when moving over another, which is a result of both reaction and action forces at play. Dynamic forces usually refer to forces that are involved during motion, without a direct emphasis on the interaction of action and reaction forces.