Problems with Newton's third Law

AI Thread Summary
When a horse pulls a cart with a force of 500 N, the cart exerts an equal and opposite force of 500 N on the horse, as stated by Newton's third law. However, the net force acting on the cart is not zero because the force exerted by the horse is what causes the cart to move. The 500 N force acting on the cart is responsible for its acceleration, while the reaction force acts on the horse. Understanding this distinction clarifies how the cart can still move despite the equal forces. The discussion concludes that recognizing the different forces acting on the horse and cart resolves the confusion.
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Homework Statement



This is more of a concept problem than one of number manipulation. I was wondering, if when a horse pulls forward on a cart with a force of 500 N and the cart pulls back with a force of 500 N by Newton's 3rd Law, how does the cart move if the net force is 0?

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The Attempt at a Solution


 
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The net force on the cart isn't 0 N, it's 500N.
The Newton 3 reaction force is acting on the horse.
 
how it is zero?..
you said that the horse pulls the cart with a force of 500N , in this case you have a force of 500N acting on the cart ..
Now, you said that by Newtons third law there should be another 500N force, but pay attention this other force is acting on the horse! not the cart, so that's why the cart is moving! .. can you see the difference now? .. if not ask again .. :)
 
Thanks a bunch, yeah it makes sense now
 

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