WBJEE · Physics · Current Electricity
An electric bulb marked as 50W-200V is connected across a \(100 \mathrm{V}\) supply. The present power of the bulb is
- A \(37.5 \mathrm{W}\)
- B \(25 \mathrm{W}\)
- C \(12.5 \mathrm{W}\)
- D \(10 \mathrm{W}\)
Answer & Solution
Correct Answer
(C) \(12.5 \mathrm{W}\)
Step-by-step Solution
Detailed explanation
We know that \[ R=\frac{V^{2}}{P} \] Given \(\quad V=200 \mathrm{V}, P=40 \mathrm{W}\) and \(\quad V=100 \mathrm{V}\) Hence, \(\quad R=\frac{V^{2}}{P}=\frac{200 \times 200}{50}\)…
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