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Sahay Sir > Question Answers > Uncategorised (JEE Advanced Physics by BM Sharma + GMP Solutions) > The emissivity of tungsten is aproximately 0.35. A tungsten sphere 1 cm in radius is suspended within a large evacuated enclosure whose walls are at 300 K. What power input is required to maintain the sphere at a temperature of 3000 K if heat conduction along the support

The emissivity of tungsten is aproximately 0.35. A tungsten sphere 1 cm in radius is suspended within a large evacuated enclosure whose walls are at 300 K. What power input is required to maintain the sphere at a temperature of 3000 K if heat conduction along the support

A thin brass rectangular sheet of sides 15.0 and 12.0 cm is heated in a furnace to 600C and taken out. How much electric power is needed to maintain the sheet at this temperature given that its emissivity is 0.250?