Question

A 12 g bullet is accelerated from rest to a speed of 700 m/s as it travels 20 cm in gun barrel. Assuming the acceleration to be constant, how large was the accelerating force?

Answer 1

m = 12 g = 12/1000 kg = 0.012 kg,
u = 0 m/s
v = 700 m/s
S (distance) = 20 cm = 20/100 m = 0.2 m

Formula used:
v² = u² + 2aS
(700)² = (0)² + 2. a. (0.2)
490000 = 0.4 a
a = 490000/0.4
a = 1225000 m/s²
Force = mass×accelaration
Force= 1225000 × 0.012
= 14700 newton