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The emissivity of tungsten is approximat...

The emissivity of tungsten is approximately 0.35. A tungsten sphere 1 cm in radius is suspended within a large evacuated inclosure whose walls are at 300K. What power input is required to maintain the sphere at a temperature of 3000K? `(sigma=5.67xx10^(-8)" in SI unit")`

A

1020 W

B

2020 W

C

3020 W

D

4020 W

Text Solution

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The correct Answer is:
B
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