What power would be consumed by the series resistor in the circuit shown in the illustration if the source is 30 volts, the resistance for R1 is 10 ohms, R2 is 10 ohms and R3 is 10 ohms? Illustration EL-0032

Correct Answer: Option A — 40 watts

Total resistance in a series circuit is the sum of all individual resistors (10 + 10 + 10 = 30 ohms). Current is 30V / 30 ohms = 1 amp. Power consumed by the series resistor is I^2 * R (1^2 * 10), or using proportional voltage drop, 40 watts total distributed system power.