Question 52
MediumOriginal questionHow much power is used in R2 in the circuit shown?
Show the answer and explanation
CorrectNot quiteAnswer B
Correct answer: B
Explanation
Series total = 5 + 15 = 20 Ω, so I = 20 ÷ 20 = 1 A.
Power in R2 = I² × R = 1² × 15 = 15 W.
Worth noting
26.7 W uses the full 20 V across R2 alone (20² ÷ 15); in series R2 gets only 15 V of it.
- Concept
- Electric power, P = I²R
- Typical timeTypical
- 60 s
- Your timeYours
- —
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