Viewing Saved Work Revert to Last Response 20. [0/1 Points] DETAILS PREVIOUS ANSWERS MY NOTES ASK YOUR TEACHER A current exists whenever electric charges move. If AQ is the net charge that passes through a surface during a time period At, then the average current during this time interval is defined as average current = AQ 22 - Q1 At t2 - t1 If we take the limit of this average current over smaller and smaller time intervals, we get what is called the current I at a given time t1: I = lim AQ _do At-0 At dt Thus the current is the rate at which charge flows through a surface. The current in a wire is defined as the derivative of the charge: I(t) = Q'(t). What does I(t) dt represent? It represents the change in the charge Q from time t = a to t = b. It represents the charge Q at time t. It represents the current I at time t. It represents the change in the current I from time t = a to t = b. X Submit