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

Question

Quizplus · Accepted Answer

The equivalent resistance of two resistors in parallel is given by:
1/Req = 1/R1 + 1/R2
1/Req = 1/4.0 + 1/4.0
1/Req = 0.5
Req = 2.0 Ω
Therefore, the equivalent circuit consists of a 2.0 Ω resistor in series with a 3.0 Ω resistor, which gives a total equivalent resistance of:
Req_total = 2.0 + 3.0 = 5.0 Ω

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