Two 4.0-Ω resistors are connected in parallel, and this combination is connected in series with 3.0 Ω. What is the effective resistance of this combination?
A)1.2 Ω
B)5.0 Ω
C)7.0 Ω
D)8.0 Ω
E)11 Ω

Question

Quizplus · Accepted Answer

The two 4.0-Ω resistors in parallel have an equivalent resistance of 2.0 Ω (1/R = 1/4 + 1/4 = 1/2, so R = 2 Ω). Adding the 3.0 Ω resistor in series gives a total resistance of 5.0 Ω (2.0 Ω + 3.0 Ω = 5.0 Ω).

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