Question

Identify action-reaction pairs in the following situations:

(a) A man takes a step.

(b) A snowball hits a girl in the back.

(c) A baseball player catches a ball.

(d) A gust of wind strikes a window.

Short answer

(a) As the man takes a step, the reaction is the force of the Earth on his foot.

(b) The action is the force exerted on the girl’s back, and the reaction is the force exerted on the snowball.

(c) The action is the force of the glove on the ball; the reaction I the force of the ball on the glove.

(d) The action is the force exerted on the window by the air molecules; the reaction is the force on the air molecules exerted by the window.

Step-by-step solution

A concept:

Action-reaction pairs are forces of equal magnitude and opposite directions acting on different objects. It never affects the same object. 3. Newton's law tells us that forces are interactions. An object cannot exert a force on another object without feeling a reaction force itself.

(a) A man takes a step:

When a person takes a step, the action is the force exerted by his foot on the ground, and the reaction is the force exerted by the Earth on his foot.

(b) A snowball hits a girl in the back:

The force the snowball puts on the girl's back is the action; the force the girl's back exerts on the snowball is the response.

(c) A baseball player catches a ball:

The action is the force of the glove on the ball; the reaction I the force of the ball on the glove.

(d) A gust of wind strikes a window:

The action is the force exerted on the window by the air molecules; the reaction is the force on the air molecules exerted by the window. In each situation, we might exchange the terms "action" and "response."