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प्रश्न
A heating element is marked 210 V, 630 W. What is the value of the current drawn by the element when connected to a 210 V dc source?
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उत्तर
In dc source, P = VI. Given that P = 630 W and V = 210 V. Therefore, `I = P/V = 630/210 = 3 A` .
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