Force Problem of normal force of the table

AI Thread Summary
The discussion centers on determining the normal force exerted by a table on a book when an additional downward force is applied by a hand. It concludes that the normal force is equal to the gravitational force (mg) plus the force applied by the hand. This is supported by Newton's Third Law, which states that forces between two bodies are equal in magnitude and opposite in direction. Therefore, the normal force must account for both the weight of the book and the additional force from the hand. The final conclusion is that the normal force is greater than mg when a hand presses down on the book.
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Homework Statement


A hand presses down on a book. Is the normal force of the table on the book larger than, smaller than, or equal to mg? (m is the book mass)


Homework Equations


F+mg


The Attempt at a Solution


I want to say the normal force is equal to mg. Am i correct?
 
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Wikipedia of Newton's 3rd Law:

Whenever a first body exerts a force F on a second body, the second body exerts a force −F on the first body. F and −F are equal in magnitude and opposite in direction.

The downward force of the book is F(weight) + F(applied by hand).
Book acting on table.

Now the table acting on book has the same magnitude of force but opposite direction (N3rd law). Force(normal).

Hope that helps.
 

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