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A modern 200 W sodium street lamp emits ...

A modern 200 W sodium street lamp emits yellow light of wavelength 0.6 `mum`. Assuming it to be 25% efficient in converting electrical energy to light, the number of photons of yellow light it emits per second is

A

`1.5xx10^(20)`

B

`6xx10^(18)`

C

`62xx10^(20)`

D

`3xx10^(19)`

Text Solution

Verified by Experts

The correct Answer is:
A
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