A hammer with 10 J of kinetic energy hits a nail and pushes it 5.0 mm into a plank.

Question

Both the hammer and nail come to rest after the collision.
What is the average force that acts on the nail while it moves the 5.0 mm?

Answer 1

KE=mv²/2
v²= 2•KE/m
a= v²/2s
F=ma=mv²/2s= 2m•KE/2s m=
= KE/s=10/0.005 =2000 N

Answer 2

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