- For every action (force), there is an equal and opposite reaction: FA = -FB
- In other words, If object A exerts a force on Object B, Then object B exerts an equal and opposite force on object A.
- Notice the negative symbol on “FB” since force is a vector quantity the “opposite” force that B is exerting on A has to be negative (Vector in the opposite direction.
![](https://phys207-project.physics.wisc.edu/angelo-madruga/wp-content/uploads/sites/7/2020/10/954152-1-768x480.jpg)
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