# Calculating current given the current density and area

1. Mar 20, 2015

### CivilSigma

Hello, I am having trouble getting the correct solution to the following problem, even though I think my steps all are correct!! What did I do wrong?

1. The problem statement, all variables and given/known data

2. Relevant equations
Current = current density * area
Current = charge/time So, time = charge / current

3. The attempt at a solution
For the first part I get: $$Current = 6.67\cdot10^6 A/m^2 * 1.41\cdot10^{-3} =9404.7A$$
For the second part I get: $$time=\frac{4.77*10^{20} electrons \cdot 1.602\cdot10^{-19} C/electron}{9404.7A}=0.00813s$$

And as I stated, I'm not getting the correct answer. As you can see my units all match up. Do you see a math error? Or have I misunderstood a concept.

Thank you,
-Sakon

2. Mar 20, 2015

### Bystander

Yes. Check your units one more time.

3. Mar 21, 2015

### CivilSigma

Thank you, know I know 1mm^2=10^-6 m^2