Monochromatic light of frequency `6.0 xx 10^(14) Hz` is produced by a laser. The power emitted is `2 xx 10^(-3)` w. The number of photons emitted, on the average, by the sources per second is

Options

A. `5 xx 10^(14)`
B. `5 xx 10^(15)`
C. `5 xx 10^(16)`
D. `5 xx 10^(17)`

Answer

B

Explanation

`n=(P)/(hv)=(2xx10^(-3))/(6.62xx10^(-34)xx6xx10^(14))=5xx10^(15)`