Question
a hammer weighing 1 kg moving with a speed of 20 m/s strikes the head of a nail driving it 10 cm into a wall. Neglecting the mass of the nail, calculate a) the acceleration during the impact, b) the time interval during impact, c) impulse.
Solution
Here,
m = 1 kg, u = 20 m/s
s = 10 cm = 0.1 m
v = 0, a = ?
a) As,
v2 = u2 + 2as
b) v = u + at 
c) Impulse = F. t
= m (v-u)
= 1 (0-20)
= -20 N.s.
