The difference between a fuse and a circuit breaker is that a fuse is a one time circuit element while a circuit breaker is a multiple use device. If you were designing a circuit for a reading lamp, you should include a circuit breaker so you don't have to replace it every time.
Final velocity = 0, thus final kinetic energy is 0
Initial kinetic energy:
0.5mv²
= 0.5 x 0.48 x 4.08²
= 4.0 J
Decrease in kinetic energy = 4 - 0 = 4 Joules
