Does Newtons 3rd law corespond with pressure?

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SUMMARY

This discussion focuses on the relationship between Newton's Third Law of Motion and the concept of pressure. When a sharp pencil is pushed against a desk, both the pencil and the desk experience equal and opposite forces, as stated by Newton's Third Law. However, the pressure exerted by the pencil differs due to its smaller surface area, calculated using the formula P = F / A. The contact surface area is identical for both objects, leading to a nuanced understanding of how force and pressure interact.

PREREQUISITES
  • Understanding of Newton's Third Law of Motion
  • Basic knowledge of pressure calculations (P = F / A)
  • Familiarity with concepts of force and area
  • Knowledge of contact mechanics
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  • Research the effects of surface area on pressure in different materials
  • Learn about contact mechanics and its applications in engineering
  • Investigate how pressure varies in different physical scenarios
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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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