Question

A carpenter swings a 3-kg hammer so that its speed is 5 m/s just before it strikes a nail. the nail is driven 6 mm into a block of wood. assuming that a constant force resisted the motion of the nail, what must have been the magnitude of the force?

Answer 1

According to question

Mass of Hammer    M = 3 Kg
Speed of Hammer     v = 5 m/sec

Distance  = v /t
   6 mm = 5/t
     0.006 = 5/t
t = 83 sec
Thus acceleration = v/t = 5/83 = 0.06 m/s^2
Thus 

F = M * a
   = 3 *  0.06
   = 0.18 N