A man squeezes a pin between his thumb and finger, as shown in figure

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A man squeezes a pin between his thumb and finger, as shown in figure.
image
The finger exerts a force of 84 N on the pinhead.
The pinhead has an area of 6.0 X 10-5 m^2.
Explain why the pin causes more pain in the man’s thumb than in his finger.

Answer:
Pressure is the force per unit area. When a force acts over a large area of the object, it produces a small pressure. But if the same force acts over a small area of the object, it produces a large pressure. In this case surface area of pintip is less than the surface area of pinhead. So pressure is more in man’s thumb.