A charge of 36 C passes through a circuit every 6 s. If the circuit can generate 6 W of power, what is the circuit's resistance?

1 Answer
Feb 18, 2016

R = (6W)/(6A)^2= (6W)/(36A) = 1/6text( Ohms) ~= 0.17 Omega
The circuit's resistance is around 0.17 Ohms.

Explanation:

The current, I, is equal to the charge passing through a point, every second.

I = dq / ds = 36C / 6 s = 6 C/s = 6 Amperes.

Now use, Power = P = I^2 R, and rearrange to make the resistance, R, the subject:

R = P/I^2
Enter known values for P and I.

R = (6W)/(6A)^2= (6W)/(36A) = 1/6text( Ohms) ~= 0.17 Omega