Question 54
MediumOriginal questionWhat is the total resistance of the circuit shown, as seen by the battery?
Show the answer and explanation
CorrectNot quiteAnswer B
Correct answer: B
Explanation
R2 and R3 in parallel: 12 × 6 ÷ (12 + 6) = 72 ÷ 18 = 4 Ω.
R1 is in series with that: 4 + 4 = 8 Ω.
Worth noting
22 Ω adds all three; 2 Ω puts all three in parallel; 13 Ω averages the parallel pair instead of combining it.
- Concept
- A series–parallel circuit
- Typical timeTypical
- 60 s
- Your timeYours
- —
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