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Does Newtons 3rd law corespond with pressure?

  1. May 19, 2010 #1
    If I were to take a standard sharp led pencil and push it on my desk, the tip of pencil will feel the same force as the force exerted on the desk, but what about the pressure?

    Since pressure is defined as:

    P = F / A

    The surface area of the tip of the sharp pencil is far smaller than the surface area of the desk, so does that mean that the pressures will be different? Or are they the same due to a resultant pressure?

  2. jcsd
  3. May 19, 2010 #2


    User Avatar

    Staff: Mentor

    Only contact surface counts, and it is identical for both objects.
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