Action–reaction pairs
What Action–reaction pairs means in Physics A-Level, as defined for AQA, OCR.
Definitions of Action–reaction pairs
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Reference: OCR
If body A exerts a force on body B, then B exerts an equal-magnitude force on A in the opposite direction, acting on a different body.
Two forces equal in magnitude, opposite in direction, of the same type, acting on two different bodies.
Topics that use Action–reaction pairs
- Newton’s laws of motion (AQA A-Level)
- Newton’s laws of motion (OCR A-Level)
Related terms
- Acceleration
- Area under a graph
- Change in momentum and direction
- Equilibrium
- Force–time graphs
- Resultant force
- Resultant force and motion
- Safety applications of impulse
Using Action–reaction pairs in the exam
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