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प्रश्न
A heating element is marked 210 V, 630 W. Find the resistance of the element when connected to a 210 V dc source.
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उत्तर
∵ Power is given as, `P= V^2/R,∴R = V^2/P = 210^2/630 = 70Ω`
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संबंधित प्रश्न
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| Current A |
Voltage V |
Current A |
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