A 4 Ω resistor and a 12 Ω resistor are connected in parallel. What is the total resistance?
Answer and explanation
Correct answer: D. 3 Ω
- Step 1: For parallel resistors .
- Step 2: , so Ω.
Answer
3 Ω.
Why not the others: 16 Ω: that is the formula for resistors in series. 8 Ω: it averages the two resistances. 48 Ω: it multiplies the resistances without dividing by their sum.
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