Electrical mathQuestion 651 of 1506

A 12 V supply feeds 100 Ω, 200 Ω and 300 Ω resistors in series. The 200 Ω resistor fails shorted. What is the new circuit current?

30 mA
20 mA
40 mA
60 mA

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Correct answer: 30 mA

The total is now 100 + 300 = 400 Ω. I = 12 V / 400 Ω = 0.03 A = 30 mA. It was 20 mA before.

Source: Lessons in Electric Circuits I: DC (Kuphaldt), 5.7: Component Failure Analysis

Questions last reviewed: 18 October 2026

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