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How many photons per second does a one w...

How many photons per second does a one watt bulb emit if its efficiency is `10%` and the wavelength of light emitted is 500 nm

A

`6.52xx10^(17)`

B

`2.53xx10^(17)`

C

`5.321xx10^(11)`

D

`6.21xx10^(12)`

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The correct Answer is:
B
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