A 10 ohm resistor is connected in series with a variable resistor and a 12 V battery. If the current is 0.5 A, what is the value of variable resistor?
Q1. A 10 ohm resistor is connected in series with a variable resistor and a 12 V battery. If the current is 0.5 A, what is the value of variable resistor?
Answer: 14 ohm
Explanation: I = V/R_total, so 0.5 = 12 / (10 + R), hence R = 14 ohm.