How Many Electrons Cross a Point in a Wire with a Given Current?

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A wire has a current given by
i (t ) =15 2 cos (2π 60t ) [A].
Determine how many electrons cross a particular point on the wire, moving from right to left, in
the time interval 0 < t < 0.001
I don't get this one. What equation do Ineed to use? I can't find the right one, but it seems so easy. :confused:
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XodoX said:
A wire has a current given by
i (t ) =15 2 cos (2π 60t ) [A].
Determine how many electrons cross a particular point on the wire, moving from right to left, in
the time interval 0 < t < 0.001

Hi XodoX! :smile:

Hint: current = charge per time, so ∫(current)d(time) = charge :wink:
 


I don't get it. Couldn't I just plug in the numbers and substract both equations?