If 5% of the energy supplied to a bulb is irradiated as visible light, how many quanta are emitted per second by a 100 W lamp? (Assume, wavelength of visible light as `5.6xx10^(-5)cm`)A. `1.4xx10^(19)`B. `3xx10^(3)`C. `1.4xx10^(-19)`D. `3xx10^(4)`

If 5% of the energy supplied to a bulb is irradiated as visible light,

1.	If 5% of the energy supplied to a bulb is irradiated as visible light, how many quanta are emitted per second by a 100 W lamp? (Assume, wavelength of visible light as `5.6xx10^(-5)cm`)A. `1.4xx10^(19)`B. `3xx10^(3)`C. `1.4xx10^(-19)`D. `3xx10^(4)`
Answer» Correct Answer - A Energy radiated as visible light `=(5)/(100)xx100=5Js^(-1)` Let n be the number of photons emitted per second. then, `nhv=E=5` `thereforen=(5lamda)/(hc)=(5xx5.6xx10^(-7))/((6.62x10^(-34))(3xx10^(8)))=1.4xx10^(19)`

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If 5% of the energy supplied to a bulb is irradiated as visible light, how many quanta are emitted per second by a 100 W lamp? (Assume, wavelength of visible light as `5.6xx10^(-5)cm`)A. `1.4xx10^(19)`B. `3xx10^(3)`C. `1.4xx10^(-19)`D. `3xx10^(4)`

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