Question

Hence,
5.4
a 10g bullet moving at 200m/s stops after penetrating 5 Cm of wooden plank. the average force exerted by the bullet will be ?
a) 2000N
b) -2000N
c) 4000N
d) -4000N

Answer 1

Given,

Mass (m) = 10 g

= 0.01 kg

Initial Velocity (u) = 200 m/s

Final Velocity (v) = 0 m/s

Distance (S) = 5 cm

= 0.05 m

v² = u²+2aS

0 = (200)² + (2*a*0.05)

-40000 = 0.1a

-400000 m/s² = a

F = ma

= 0.01*(-400000) N

= -4000 N (Option d)

I hope this helps.