Does Newtons 3rd law corespond with pressure?

AI Thread Summary
When a sharp pencil is pushed against a desk, the tip experiences the same force as the desk but has a significantly smaller surface area. Pressure, defined as P = F / A, indicates that the pressure exerted by the pencil tip is greater than that on the desk due to its smaller area. This leads to the conclusion that while the forces are equal, the pressures differ because of the varying contact surfaces. The discussion emphasizes that only the contact surface area matters for pressure calculations. Thus, the pressures are not the same, as the resultant pressure is influenced by the area of contact.
zeromodz
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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?


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

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