Popeye,of mass 70 kg,has just downed a can of spinach.He accelerates quickly and stops Bluto,of mass 700 kg (Bluto is very dense),who is charging in at 5.0 m/s.What was Popeye's remarkable speed?
A) 10 m/s
B) 31 m/s
C) 50 m/s
D) 100 m/s

Question

Quizplus · Accepted Answer

Using the conservation of momentum, the initial momentum of Bluto (700 kg * 5 m/s = 3500 kg*m/s) must equal the momentum of Popeye (70 kg * v) since he stops Bluto. Solving for v gives v = 3500 kg*m/s / 70 kg = 50 m/s.

Popeye,of Mass 70 Kg,has Just Downed a Can of Spinach