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An electric heater radiates 1000 W of thermal power from a coil of surface area 0.020 m². Treating the coil as a blackbody, find its temperature. Use Stefan's constant sigma = 6.00 * 10⁻⁸ W m⁻² K⁻⁴.

1. 955 deg C
2. 955 K
3. 1025 deg C
4. 1025 K

Correct answer: 955 K

Solution

From P = sigma*A*T⁴, T = (1000/(6e-8 * 0.020))^(1/4) which is about 955 K.

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