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प्रश्न
A hammer of mass 500 g, moving at 50 ms−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?
उत्तर
The force of the nail on the hammer,
F = `"Change in momentum of hammer"/ "Time"`
F = `(m (v - u))/t`
F = `(0.50 kg (0 - 50 ms^-1))/(0.01 s)`
F = `(0.50 kg (0 - 50 ms^-1))/(0.01 s)`
F = -2500 N
The minus sign denotes the force that the nail applies to the hammer when it acts in the opposite direction of the hammer.
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