In a certain material there is a current of 18 A flowing through a surface to the right,and there is an equal amount of positive and negative charge passing through the surface producing the current.How much negative charge passes through the surface?
A)9 C/s toward the right
B)9 C/s toward the left
C)18 C/s toward the right
D)18 C/s toward the left
E)36 C/s toward the left

Question

Quizplus · Accepted Answer

Since the current is 18 A and is produced by an equal amount of positive and negative charge moving through the surface, half of this current, or 9 A, can be attributed to the movement of negative charges. Current direction is opposite to the movement of negative charges, so if the current is to the right, the negative charges move to the left, making 9 C/s toward the left the correct answer.

In a Certain Material There Is a Current of 18