Who has more power:
A: 500 Joules of work in 300 minutes.
B: 800 Joules or work in 400 minutes.

A monochromatic source emitting light of wavelength 600 nm has a power output of 66 W. Calculate the number of photons emitted by this source in 2 minutes.

A person holds a bundle of hay over his head for 30 minutes and gets tired. Has he done some work or not? Justify your answer.

A man weighing 49 kg carries a bag of 2 kg . He climbs to the top of a building 100 m tall in 5 minute . Calculate the work done by the man and the power he develops .

4 xx 10^(-4) joules of work is done in moving a charge of 5 microcoulomb from a point A to another point B. Then the potential difference between A and B is