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Question
A heating element is marked 210 V, 630 W. Find the resistance of the element when connected to a 210 V dc source.
Solution
∵ Power is given as, `P= V^2/R,∴R = V^2/P = 210^2/630 = 70Ω`
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RELATED QUESTIONS
What conclusion can you draw from the following observations on a resistor made of alloy manganin?
| Current A |
Voltage V |
Current A |
Voltage V |
| 0.2 | 3.94 | 3.0 | 59.2 |
| 0.4 | 7.87 | 4.0 | 78.8 |
| 0.6 | 11.8 | 5.0 | 98.6 |
| 0.8 | 15.7 | 6.0 | 118.5 |
| 1.0 | 19.7 | 7.0 | 138.2 |
| 2.0 | 39.4 | 8.0 | 158.0 |
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