Physicshard · Past Paper
A 100W-220V bulb and a 60W-220V bulb are connected in series to a 220V supply. What is the total power consumed by the bulbs together?
A160 W
B37.5 W
C80 W
D100 W
✓ Correct Answer: B — 37.5 W
R1=V^2/P1=484, R2=V^2/P2=806.6. R_total=1290.6. P_total=V^2/R_total = 48400/1290.6 ≈ 37.5W.
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