Newton's Third Law: Equal & Opposite Forces?

AI Thread Summary
Newton's Third Law states that for every action force, there is an equal and opposite reaction force, but this does not imply that the forces are balanced. For example, when a person walks, they exert a downward force on the ground, which propels them forward, while the Earth exerts an equal and opposite force that does not result in a balanced state. The key distinction is that these forces act on different bodies, meaning they do not cancel each other out. Newton's Second Law explains that acceleration occurs due to a net force, which can exist even when forces are equal and opposite. Therefore, while the forces are equal and opposite, they do not create a balanced system.
Faded Maximus
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Newtons third law states that for every force there is an equal an opposite force. This doesn't mean that these forces are balanced though? Things like cars or people walking can still accelerate so these forces can't be balanced?
 
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When you walk you push down on the ground and it moves you forwards.

At the same time, the Earth pushes back on you and moves backwards.

Equal and opposite.
 
Since they are equal and opposite though, would that imply that they are balanced forces?
 
The proper statement of Newton's third law is:

If body A exerts a force on body B, then body B exerts a force on body A that is equal in magnitude and opposite in direction to the force exerted by body A.

By definition, they are equivalent. Newton's 2nd law deals with accelerations due to a net force.
 
Faded Maximus said:
Since they are equal and opposite though, would that imply that they are balanced forces?

The answer is no because the two forces act on different bodies.
 

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