Q. 25.0( 2 Votes )
If someone presses a pointed needle against your skin, you are hurt. But if someone presses a rod against your skin with the same force, you easily tolerate. Explain.
The pressure (P) on any surface depends on the force(F) and area(A) as given by:
Now, lesser the area of contact of the object, higher will be the pressure. In case of a needle, the area of contact is just a point as compared to a rod. Hence the same amount force will produce a larger pressure in case of a needle, because of which we can get hurt.
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