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Homework Help: Gravitational force and normal force.

  1. Dec 7, 2013 #1
    1. The problem statement, all variables and given/known data

    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

    2. Relevant equations


    3. 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?
  2. jcsd
  3. Dec 7, 2013 #2


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    Staff Emeritus
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    Homework Helper

    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.
  4. Dec 7, 2013 #3
    ok I didn't taught about the free body diagram thanks.
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