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?
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/s2
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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