Is the Total Force Between a Book and the Earth 10 N?

AI Thread Summary
The discussion centers on the forces between a book and the Earth, specifically questioning whether the total force is 10 N due to Newton's third law. It clarifies that while the Earth pulls the book with 5 N and the book pulls the Earth with 5 N, these forces do not sum to create a total force of 10 N acting on either object. Instead, the relevant force acting on the book is solely the 5 N from the Earth, which is the force needed to lift it. Any additional forces acting on other objects in the vicinity would depend on their mass and the gravitational influence from both the Earth and the book, but they would not experience a combined force of 10 N. Therefore, the total force between the book and the Earth remains 5 N in terms of lifting the book.
defetey
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This is not really a homework question, just a question I came up with. If the Earth is pulling, for example, a book with a force of 5 N, that means, due to Newton's 3rd law, that the book is also pulling the Earth with a force of 5 N.

Does this mean the total force between them is actually 10 N (since they are each pulling each other with a force of 5 N)? That would imply you would need over 10 N to pick up the book, but I know you only need anything over 5 N. So what am I missing here?
 
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defetey said:
This is not really a homework question, just a question I came up with. If the Earth is pulling, for example, a book with a force of 5 N, that means, due to Newton's 3rd law, that the book is also pulling the Earth with a force of 5 N.

Does this mean the total force between them is actually 10 N (since they are each pulling each other with a force of 5 N)? That would imply you would need over 10 N to pick up the book, but I know you only need anything over 5 N. So what am I missing here?

I believe it is because the only forces being exerted on the book are by you and the earth. Whatever force the book exerts on anything else is irrelevant; the only relevant forces are the ones acting on the book.
 
But if something was between them, would it experience 10 N of force (5 from the book and 5 from the Earth)?
 
no it wouldn't ... gravitational force is field force acting on any mass by any mass..
So the thing in between would experience a force based on it mass according to Newtons law of gravitation by both the Earth and the book but their magnitudes would be different(not 5N).

And there's no 10N force ... since 5 acts on the book and 5 on the Earth which are both separate bodies.
 
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