could someone plz help me with the following
A particular filament rating of 60W emits 5% of this power as visible light. The average wavelength of visible light is 550nm.
Calculate the number of photons of visible light emitted per second from the lamp.
Thanks
The 5% power is defined as the energy required for
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number of photons to be emitted per second.
Hence Power =
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x
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where
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= photon energy =
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/lambda
Power =
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x
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/lambda -----> 5/100 x 60 =
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x (6.63 x 10
-34) x (3 x 10
8) / (550 x 10
-9)
Thus
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is found to be
8.3 x 1018 which is the required answer.
Sorry for late reply...........but I was kinda busy.
