Question

If a 50microAmps current is flowing then how many electrons pass a point each minute to 2 sig figs? Please add an explanation as I'm completely lost.

Answer 1

The equation you need to use is $Q=IT$ where Q is the charge in C, I is the current in Amps and T is the time in seconds.

So we have T = 60s
I = $50 \times 10^-^6$A
let's work out Q
$Q=IT = (50\times 10^{-6}) \times 60 = 3 \times 10^-^3$C
this is the total charge passing a point in a minute so divide by the charge of one electron ($1.6 \times 10^{-19}$) to find the number of electrons passing the point in a minute which equals $1.875 \times 10^{16}$