Question

A point source emitting photons of 2 eV energy and 1 W of power is kept at a distance of 1m from a small piece of a photoelectric material of area 10-4 m2 . If the efficiency of generation of photoelectrons is 10%, then the number of photoelectrons generated are 𝑓×1012 per second. The value of 𝑓 is __________ (rounded off to two decimal places).
Given: 1eV = 1.6 × 10−19 J

Answer 1

The correct answer is: 2.3 to 2.70 (approx)