Question 3

A hammer of mass 500 g, moving at 50 m s^{-1}, strikes a nail. The nail stops the hammer in a very short time of 0.01 s. What is the force of the nail on the hammer?

Answer

Mass of the hammer, *m* = 500 g = 500 / 1000 = 0.5 kg

Initial velocity of the hammer, *u* = 50 m/s

Time taken, *t* = 0.01

Since the hammer comes to rest,

Velocity of the hammer, *v* = 0

Using Newton’s second law of motion:

The hammer strikes the nail with a force of −2500 N. By Newton’s third law of motion, nail exerts an equal force in the opposite direction on the hammer, thus the force of the nail on the hammer is equal and opposite, i.e., +2500 N.

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- NCERT Chapter

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