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If mean wavelength of light radiated by ...

If mean wavelength of light radiated by `100 W` lamp is `5000 Å` , then number of photons radiated per second are

A

`3 xx 10^(23)`

B

`2.5 xx 10^(22)`

C

`2.5 xx 10^(20)`

D

`5 xx 10^(17)`

Text Solution

Verified by Experts

The correct Answer is:
C
`P = (nhc)/(lambda t) rArr (n)/(t) = (P . lambda)/(hc) = (100 xx 5000 xx 10^(-10))/(6.6 xx 10^(-34) xx 3 xx 10^(8))`
`= 2.50 xx 10^(20)`
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