Question

(a) Monochromatic light of frequency $6.0\times {10}^{14}Hz$ is produced by a laser. The power emitted is $2.0\times {10}^{-3}W$. Estimate the number of photons emitted per second on an average by the source.
(b) Draw a plot showing the variation of photoelectric current versus the intensity of incident radiation on a given photosensitive surface.

Answer 1

(A). $power=\frac{Energy}{sec}=\frac{nhv}{sec}n/sec.=\frac{power}{hv}=\frac{2\times {10}^{-3}}{6.6\times {10}^{-34}\times 6\times {10}^{14}}=5\times {10}^{15}$

(B).