Calculate the energy radiated is one minute by a blackbody of surface area `200 cm^2` at `127^@C` (`sigma = 5.7 xx 10^-8 Jm^-2s^-1K^-4`)

Calculate the energy radiated in one minute by a black body of surface area 100 cm^2 when it is maintained at 227^@C ( sigma= 5.67 xx 10^-8 J/m^2sK^4 )

Calculate the energy radiated is one minutes by a black body of surface area 400cm^2 ,when it is maintained at 127^@C .

The energy of 6000 J is radiated in 5 minutes by a body of surface area 100 cm^2 . Find emissive power of a body.

Calculate the energy radiated in 30 seconds by perfectly black sphere of radius5cm maintained at 127^@C . (Stefan's constant s = 5.7 xx 10^-8 J//m^2sk^4)

A small blackened solid copper sphere of radius 2.5cm is placed in an evaculated chamber. The temperature of the chamber is maintained at 100^@C . At what rate energy must be supplied to the copper sphere to maintain its temperature at 110^@C . ( sigma = 5.76 xx 10^-8 Js^-1m^-2K^-4 ) Treat sphere as black body.

Assuming that the sun radiates as a black body, calculate the energy radiated per minute by unit area of its surface. Surface temperature of the sun = 5727^@C and Stefan's constant = 5.7 xx10^-8 Jm^-2K^-4s^-1 .

A 60 watt filament lamp loses all its energy by radiation from its surface. The emissivity of the surface is 0.5. The area of the surface is 5 xx 10^-5m^3 . Find the temperature of the filament ( sigma = 5.67 xx 10^-8m^2s^-4K^-4 )

Energy is emitted from a hole in an electric furnace at the rate of 20W when that temperature of the furnace is 727^@C . What is the area of the hole ( sigma = 5.7 xx 10^-8 Js^-1m^-2K^-4 )