A 100 W light bulb has a tungsten filament (emissivity = 0.30) which i – McqOptions

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1.	A 100 W light bulb has a tungsten filament (emissivity = 0.30) which is required to operate at 2780 K. If the bulb is completely evacuated, calculate the minimum surface area of the tungsten filament
A.	0.98 * 10 <sup>-4</sup> m<sup>2</sup>
B.	1.98 * 10 <sup>-4</sup> m<sup>2</sup>
C.	2.98 * 10 <sup>-4</sup> m<sup>2</sup>
D.	3.98 * 10 <sup>-4</sup> m<sup>2</sup>
Answer» B. 1.98 * 10 <sup>-4</sup> m<sup>2</sup>

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