A monochromatic light of frequency `3xx10^(14)Hz` is produced by a LASER, emits the power of `3xx10^(-3)` W. Find how many number of photons are emitted per second.

Options

A. `1.5xx10^(16)`
B. `2.5xx10^(16)`
C. `4.5xx10^(16)`
D. `8.5xx10^(16)`

Answer

A

Explanation

(a) : Energy of a photon, E + hv
`E=(6.63xx10^(-34)s)(3xx10^(14)Hz)-19.89xx10^(-20)J`
Power of the source, `P=3xx10^(-3)W`
Number of photons emitted per second,
`N=(P)/(E)=(3xx10^(-3)W)/(19.89xx10^(-20)J)=1.5xx10^(16)`