A 100 W lamp operated on a 120 V circuit has a current (assumed steady) of 0.83 A in its filament. We have to find the time in which 1 mol of electrons will pass through the lamp.

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The current flowing through the filament of the lamp is 0.83 A. Therefore, 0.83 C pf charge carried by electrons passes through the filament per second. As the charge of an electron is , the number of electrons that flow out through the filament per second will be

The time required for one mol of electrons, that is electrons to pass through the filament will be

As

we have