Question

While running, a person dissipates about 0.60 J of mechanical energy per step per kilogram of body mass. If a 62 kg person develops a power of 67 W during a race, how fast is the person running? (Assume a running step is 1.5 m long.)

Answer 1

A 62 kg person produces 0.60*62 = 37.2 J of work per step (1.5 m). That is 24.8 J per meter.
Power in Watts (J/s) is V (m/s)*24.8 J/m
67 = 24.8 V
V = 2.7 m/s

Answer 2

thank you so much drwls