A bulb emits light of wavelength `4500Å` .The bilb is nrated as `150` and `8%` of the energy is emmitted as light .How amny photon are emitted by the bulb per second?

A bulb emits light of wavelength `4500Å` .The bilb is nrated as `150`

1.	A bulb emits light of wavelength `4500Å` .The bilb is nrated as `150` and `8%` of the energy is emmitted as light .How amny photon are emitted by the bulb per second?
Answer» A `150 W` bulb emits `150 J` of energy per second .The energy emitted by the bulb as light is `150 xx (8)/(100) = 12 J` Let the bulb emit n potons per second `E = nhv = (nhv)/(lambda)` `:. N = (E xx lambda)/(c xx h)` `= (12 J xx 45000 xx 10^(-19)m)/(3 xx 10^(8) ms^(-1) xx 6.63 xx 10^(-34) Js)` `= 2.715 xx 10^(19)`

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A bulb emits light of wavelength `4500Å` .The bilb is nrated as `150` and `8%` of the energy is emmitted as light .How amny photon are emitted by the bulb per second?

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