If a 12v battery is in a circuit with two resistors. r1 and r2. R2 is 60ohms. A voltmeter measuring on either side of r2 gives a reading of 8v.

Calculate the current in the circuit and the resistance of r1.

Am I right in thinking the v = i/r
8 = 7.5 / 60
so the current is 7.5amps

Would this mean I could work out the total resistance by multiplying the original 12v by the current?
12 x 7.5 = 90 meaning r1 = 30?

1 answer

NO. V=IR, so I=V/R=8/60 amps