A certain dye absorbs light of `lamda = 4000 Å` and then fluresces light of `5000 Å`. Assuming that under given conditions `50 %` of the absorbed energy is re-emitted out as fluorescence, calculate the ratio of number of quanta emitted out to the number of quanta absorbed.A. `(5)/(8)`B. `(8)/(5)`C. `(3)/(8)`D. `(8)/(3)`

A certain dye absorbs light of `lamda = 4000 Å` and then fluresces li

1.	A certain dye absorbs light of `lamda = 4000 Å` and then fluresces light of `5000 Å`. Assuming that under given conditions `50 %` of the absorbed energy is re-emitted out as fluorescence, calculate the ratio of number of quanta emitted out to the number of quanta absorbed.A. `(5)/(8)`B. `(8)/(5)`C. `(3)/(8)`D. `(8)/(3)`
Answer» Correct Answer - A (a) `E_(emit ted)= (50)/(100) xx E_(ab so rbed)` No. of emitted photons `xx` Energy of emitted photon `= (50)/(100)` `xx` No . Of absorbed photon xx Energy of absorbed photon. `:. n_e xx (12400)/(5000) = (50)/(100) xx n_a xx (12400)/(4000)` `:. (n_e)/(n_a) = (5)/(8)`.

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