Question

The 8-cm-long nail is embedded into the wood wall on its half-length. You take a 2.9 kg hummer and strike the nail, completely embedding the nail into the wall. The initial speed of the hummer is 12 m/s. What is the average force acting on the nail?

Answer 1

given
mass of the hammer, m = 2.9 kg
initial velocity, vi = 12 m/s
final velocity, vf = 0 m/s
displaceent, d = 8/2 = 4 cm = 0.04 m

let a is the acceleration of the hammer, a = (vf^2 -vi^2)/(2*d)

= (0^2 - 12^2)/(2*0.04)

= -1800 m/s^2

The average of magnitude of force acting on the hammer, F = m|a|

= 2.9*1800

= 5220 N

According to Newtons third law the hammer also exerts the same amount of force on the nail.

so, the average force acting on the nail = 5220 N <<<<<<<<------------Answer