A 6 Ω resistor and a 12 Ω resistor are connected in parallel. What is the total resistance?
Answer and explanation
Correct answer: C. 4 Ω
- Step 1: For parallel resistors .
- Step 2: , so Ω.
Answer
4 Ω.
Why not the others: 18 Ω: that is the formula for resistors in series. 9 Ω: it averages the two resistances. 72 Ω: it multiplies the resistances without dividing by their sum.
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