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")

The emissivity of tungsten is approximately 0.35. A tungsten sphere 1

1.	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")
Answer» 1020 W 2020 W 3020 W 4020 W Answer :B