`10^-3` W of `5000A` light is directed on a photoelectric cell. If the current in the cell is `0.16muA`, the percentage of incident photons which produce photoelectrons, isA. `40%`B. `0.04%`C. `20%`D. `10%`

`10^-3` W of `5000A` light is directed on a photoelectric cell. If the

1.	`10^-3` W of `5000A` light is directed on a photoelectric cell. If the current in the cell is `0.16muA`, the percentage of incident photons which produce photoelectrons, isA. `40%`B. `0.04%`C. `20%`D. `10%`
Answer» Correct Answer - B Number of photons falling per second : `N_p=(10^-3)/((6.6xx10^-34xx3xx10^8)/(5000xx10^-10))=2.5xx10^15` Let `N_e` is the number of photoelectrons emitted per second. `I=(q)/(t)=(N_ee)/(1)impliesN-e=(I)/(e)=(0.16xx10^-6)/(1.6xx10^-19)=10^12` percentage of photons producing photoelectrons `=(N_e)/(N_p)xx100=(10^12)/(2.5xx10^15)xx100=0.04%`

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`10^-3` W of `5000A` light is directed on a photoelectric cell. If the current in the cell is `0.16muA`, the percentage of incident photons which produce photoelectrons, isA. `40%`B. `0.04%`C. `20%`D. `10%`

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