# Work done by moving electrons through electric potential?

## Homework Statement

A parallel-plate capacitor is charged to an electric potential of 100 V by moving 4x10^19 electrons from one plate to the other. How much work was done?

## Homework Equations

How much work was done?

## The Attempt at a Solution

Work is then simply equals to -q*deltaV. Q= number of electrons times charge per electron.

W= +4E19 * 1.6E-19 * 100= 640 J

But the answer I was given was 320 J. I don't see a divisible of 2 anywhere that I can account for.

cepheid
Staff Emeritus
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## Homework Statement

A parallel-plate capacitor is charged to an electric potential of 100 V by moving 4x10^19 electrons from one plate to the other. How much work was done?

## Homework Equations

How much work was done?

## The Attempt at a Solution

Work is then simply equals to -q*deltaV. Q= number of electrons times charge per electron.

W= +4E19 * 1.6E-19 * 100= 640 J

But the answer I was given was 320 J. I don't see a divisible of 2 anywhere that I can account for.