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The power of a heater is 500W at 800^(@)...

The power of a heater is 500W at `800^(@)C`. What will be its power at `200^(@)C` it `alpha=4xx10^(-4)` per `.^(@)C`?

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To find the power of the heater at 200°C given its power at 800°C and the temperature coefficient of resistance, we can follow these steps: ### Step 1: Understand the relationship between power and resistance The power \( P \) of a heater can be expressed as: \[ P = \frac{V^2}{R} \] Where \( V \) is the voltage and \( R \) is the resistance. Since the voltage remains constant, we can relate the power at two different temperatures with their respective resistances. ...
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