The action and reaction forces described by Newton's third law
Correct answer: B. act on different bodies and therefore never cancel
- A. act on the same body and cancel out
- B. act on different bodies and therefore never cancel
- C. are unequal in magnitude
- D. act in the same direction
Explanation
The pair is equal in magnitude and opposite in direction but acts on two different bodies, which is why they cannot cancel each other and why motion is possible at all. When you push a wall, your force acts on the wall and the wall's force acts on you. Forces only cancel when they act on the same body.
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About Newton's Laws of Motion
Newton’s laws explain inertia, the relation between net force and acceleration, and action-reaction pairs. Questions involve free-body diagrams, balanced and unbalanced forces, F = ma, force as the rate of change of momentum, and identifying genuine third-law pairs, which act on different bodies.
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