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**

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