Q. 34.3( 42 Votes )

# 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 :

Given,

Mass, m = 500 g

= kg

= 0.5 kg

Initial velocity, u = 50 m/s

Final velocity, v = 0 (As the hammer stops)

Acceleration, a =?

Time, *t* = 0.01 s

We know that,

v = u + at

0 = 50 + a × 0.01

0.01 a = - 50

a *=* -

*=* - 5000 m/s^{2}

We know that:

Force, F = m × a

F = 0.5 × (- 5000)

= - 2500 N

Here, the negative sign indicated that this force is opposing motion.

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