A 4 Ω resistor and a 3 Ω resistor are connected in parallel. What is the total resistance?
Answer and explanation
Correct answer: B. 12/7 Ω
- Step 1: For parallel resistors .
- Step 2: , so Ω.
Answer
12/7 Ω.
Why not the others: 7 Ω: that is the formula for resistors in series. 7/2 Ω: it averages the two resistances. 12 Ω: it multiplies the resistances without dividing by their sum.
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