Question

Shoveling snow can be extremely taxing since the arms have such a low efficiency in this activity. Suppose a person shoveling a sidewalk metabolizes food at the rate of 800 W. (The efficiency of a person shoveling is 3%.)

(a) What is her useful power output (in W)?

(b) How long (in s) will it take her to lift 2,500 kg of snow 1.20 m? (This could be the amount of heavy snow on 60.0 ft of sidewalk.)

(c) How much waste heat (in J) will she generate in the process?

Answer 1