Gravitational force and normal force.

AI Thread Summary
A 0.25kg book experiences a downward force of 9.5 N from a hand pushing on it. The weight of the book, calculated using F=ma, is approximately 2.45 N. To find the normal force exerted by the table, one must consider both the gravitational force and the additional force from the hand. The normal force is the sum of the weight and the applied force, resulting in a total of 11.95 N. Utilizing a free body diagram can help clarify the equilibrium of forces acting on the book.
jimmyboykun
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Homework Statement



1) A 0.25kg book rest on a table. A downward force of 9.5 N is exerted on the top of the book by a hand pushing down on the book.

2)what is the size of the normal force exerted by the table on the book

Homework Equations



F=ma

The Attempt at a Solution



1) what I did 0.25kg*9.81m/s^2= 2.4525N and I then 2.4525N+9.5N= 11.95N

2) wouldn't the normal force be equal to the weight(gravity) so wouldn't the answer be 11.95N or could I subtract 11.95 from 9.5N?
 
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If you draw a free body diagram of the book and the force from the hand pressing down, the magnitude of the normal force keeping the book in equilibrium will become crystal clear.
 
SteamKing said:
If you draw a free body diagram of the book and the force from the hand pressing down, the magnitude of the normal force keeping the book in equilibrium will become crystal clear.

ok I didn't taught about the free body diagram thanks.
 
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