Using second law of motion, derive the relation between force and acceleration. A bullet of 10 g strikes a sand-bag at a speed of 103 ms^-1 and gets embedded after travelling 5 cm. Calculate:
(i) The resistive force exerted by the sand on the bullet

(ii) The time taken by the bullet to come to rest.

Question

Philoid · Accepted Answer

(i) Given,

m = 10g = kg

u = 10³ m/s

v = 0, s = 5cm = m

v² – u² = 2as

0 – (10³)² = 2 × a ×

-(10³) × (10)³ =

a = (-1000 × ) × 100

= -10⁷ ms^-2

F = ma

= 1/100x - 10⁷

= -10⁵ N

(ii) v = u +at

0 = (10³) – 10⁷ × t

t =

t = 10^-4s

Using second law of motion, derive the relation between force and acceleration. A bullet of 10 g strikes a sand-bag at a speed of 103 ms-1 and gets embedded after travelling 5 cm. Calculate:(i) The resistive force exerted by the sand on the bullet(ii) The time taken by the bullet to come to rest.