Physics question

Question

A 126 kg railroad car carrying a 53.5 kg passenger travels alone on a level frictionless track with a constant horizontal speed of Vx = 12.6 m/s. At some later time the person riding on the car jumps up (with vertical speed of Vy = +3.0 m/s) and onto an overhanging tree limb. What is the car's new speed?

Answer 1

Since the car is traveling at a constant speed of 12.6 m/s, then all things (or persons) in it are also traveling at 12.6 m/s. So if one person jumps up to an overhanging tree, the car still continues at 12.6 m/s.

 

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