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A 2 mW laser operates at a wavelength of...

A 2 mW laser operates at a wavelength of 500 nm. The number of photons that will be emitted per second is: [Given Planck’s constant `h = 6.6 xx 10^(-34)Js`, speed of light `c = 3.0 xx 10^(8) m//s`]

A

`5 xx 10^(15)`

B

`1 xx 10^(16)`

C

`1.5 xx 10^(16)`

D

` 2xx 10^(16)`

Text Solution

Verified by Experts

The correct Answer is:
A
Number of photons = `("Power")/((hc//lambda))= 5 xx 10^(15) s .`
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