A source emits monochromatic light of frequency 5.5×1014 Hz at a rate of 0.1 W. Of the photons given out, 0.15% fall on the cathode of a photocell which gives a current of 6μA in an external circuit.
a. Find the energy of a photon.
b. Find the number of photons leaving the source per second.
c. Find the percentage of the photons falling on the cathode which produce photoelectrons.