according to newton's 3rd law, an action reaction pair of forces have equal magnitudes in the same direction or equal magnitudes in opposite direction?

Explanation:

According to newton's 3rd law of motion, the action and reaction force act in two different objects. For every action, there is an equal and opposite reaction.

Let F₁₂ is the force that object 1 experienced on object 2 and F₂₁ is the force that object 2 will experience on object 2. So,

F₁₂ = -F₂₁

So, an action-reaction pair of forces have equal magnitudes in the opposite direction.

c because the action was the roller coaster reaches bottom of hill (action) reaction would be blood tends to drain away from head

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