Question

Determine the total charge entering a terminal between t = 1 and t = 2 s and t = 2 s if the current passing the terminal is I = (3t² -t) A.

Answer 1

$dq=Idt,$

$q=\intop_1^2(3t^2-t)dt=(t^3-0.5t^2)|_1^2=5.5~C.$