Question

A student who weighs 500 newtons climbed the stairs from the first floor to the third floor, 15 meters above,
in 20 seconds.
a. How much work did she do?
b. What was her power?

Answer 1

Well, the 20 seconds gives us enough information to actually calculate the power she has on her feet :)

Well, the work is 500*15=7500J, that is 7.5 kJ or about 18 calories (1 cal is 418J?) The power is that 7.5 kJ divided by 20 seconds: 375W. That's... OK, I suppose...