A thin brass rectangular sheet of sides 10 cm and 5 cm is heated in a furnace to 500^(@) C and taken out. How much electric power is needed to maintain the sheet at this temperature ? Its emissivity is 0.25.

A thin brass rectangular sheet of sides 10 cm and 5 cm is heated in a

1.	A thin brass rectangular sheet of sides 10 cm and 5 cm is heated in a furnace to 500^(@) C and taken out. How much electric power is needed to maintain the sheet at this temperature ? Its emissivity is 0.25.
Answer» SOLUTION :`Q=esigmaT^(4)A=0.25xx5.67xx10^(-8)XX(773)^(4)xx10^(-2)=50.62` W