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The number of photons of wavelength 540 ...

The number of photons of wavelength `540 nm` emitted per second by an electric bulb of power `100 W` is (taking `h = 6 xx 10^(-34) sec`)

A

100

B

1000

C

`3 xx 10^(20)`

D

`3 xx 10^(10)`

Text Solution

Verified by Experts

The correct Answer is:
B
Power =` (Nhc)/(lamda)`
`implies100 = (Nxx(6xx10^(-34))(3xx10^(8)))/(540 xx 10^(-9))`
`implies N (100xx540 xx 10^(-9))/(18 xx 10^(-26))= 3 xx10^(20)`
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Knowledge Check

  • The number of photons emitted per second by a 62W source of monochromatic light of wavelength 4800 A^(@) is

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