Question

A  100 W lamp has steady current of 0.83 A in its filaments. How long is required for 1 mol electrons to pass through the lamp?

Answer 1

Explanations & Calculations

• The current is given and let's assume the amount does not change.
• Then you can calculate how much charge does a mole of elections include.

$\qquad\qquad \begin{aligned} \small \text{Charge} &=\small 6.023\times10^{23}\times(-1.6\times10^{-19}C) \end{aligned}$

• Once this is calculated, you can proceed with the formula $\small Charge = Current\times time$ to calculate the time it would take for that amount to flow.

$\qquad\qquad \begin{aligned} \small 6.023\times10^{23}\times|-1.6\times10^{-19}C|&=\small 0.83\,A\times t \end{aligned}$

• The t in the equation gives the time, you can give it a try.