A 100 W point source emits monochromatic light of wavelength `6000 A` Q. Calculate the total number of photons emitted by the source per second.A. `5xx10^(20)`B. `8xx10^(20)`C. `6xx10^(21)`D. `3xx10^(20)`

A 100 W point source emits monochromatic light of wavelength `6000 A`

1.	A 100 W point source emits monochromatic light of wavelength `6000 A` Q. Calculate the total number of photons emitted by the source per second.A. `5xx10^(20)`B. `8xx10^(20)`C. `6xx10^(21)`D. `3xx10^(20)`
Answer» Correct Answer - D Energy of a photon of wavelength `lamda`, `E=hv=((hc)/(lamda))` `E=((6.6xx10^(-34))xx(3xx10^(8)))/(6000xx10^(-10))` `=3.3xx10^(-19)J` So, if n is the number of photons emitted per second, `nE=("energy")/("second")="power"(P)` Hence, `n=(P)/(E)=(100)/(3.3xx10^(-19))` `approx3xx10^(20)`, photons `s^(-1)`

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A 100 W point source emits monochromatic light of wavelength `6000 A` Q. Calculate the total number of photons emitted by the source per second.A. `5xx10^(20)`B. `8xx10^(20)`C. `6xx10^(21)`D. `3xx10^(20)`

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