«

»

Current in Parallel Circuits

[poll id=”161″]

ANSWER

C. 2.5A

Begin by finding the total resistance of this circuit. Because this is a parallel circuit, total resistance is measured with the formula: 1/R = 1/R1 + 1/R2 e.t.c.

1/R = 1/8 + 1/8 + 1/4 = 1/2

Thus, R=2Ω

To find the current of I3, use the formula: I = V/R

I = 10/4Ω = 2.5A

If one wanted to confirm their answer, they could find the currents of the other resistors and add up them. They should add up to the total current (I = V/R = 10/2Ω = 5A).