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प्रश्न
An electric bulb is marked 100 W, 250 V. How much current will the bulb draw if connected to a 250 V supply?
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उत्तर
Given 250 V, I = ?
∵ P = VI
⇒ 100 = 250 × I
∴ I = `100/250 = 0.4` Amp.
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