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Question
Three bulbs B1 (230V, 40W), B2 (230V, 60W) and B3 (230V, 100W) are connected in series to a 230V supply. Which bulb glows the brightest?
Solution
The bulb B1 (230V, 40W) will glow the brightest when connected in series with B2 and B3 because the resistance `(R = V^2/P)` is highest for B1.
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