Determine the surface area of the filament of a 100W incandescent lamp radiating out its labelled power at 3000K. Given `sigam = 5.7 xx 10^(-8)Wm^(-2)K^(-4)`, and emissivity `epsilon` of the material of the filament = 0.3.

What will be the surface area of a filament of 200 W incandescent lamp at 2000 K. sigma = 5.67 xx 10^(-8) Wm^(-2) K^(-4) and emissivity e = 0.3?

Calculate the temperature (in K) at which a perfect black body radiates energy at the rate of 5.67W cm^(-2) . Given sigma = 5.67 xx 10^(8)Wm^(-2)K^(-4) .

At what temperature will the filament of 100 W lamp operate if it is supposed to be perfectly black of area 1 cm^(2) . Given sigma = 5.67 xx 10^(-5) erg cm^(-2) s^(-1) K^(-4) .

An electric bulb has a filameent of surface area 20" cm"^(2) . The filament is raised to a temperature of 1727^(0)C , when a current passes through it. If Stefan.s constant is 5.7xx10^(-8)W//m^(2)k^(4) and the emissivity of the filament is 0.5, the electric power being consumed to maintain this temperature is

The radiant power of a furnace of surface area of 0.6m^(2) is 34.2KW The temperature of the furance s [sigma = 5.7 xx 10^(-8) Wm^(-2) K^(-4) .

The power of a black body at temperature 200K is 544 watt. Its surface area is (sigma = 5.67 xx 10^(-8) wm^(-2) K^(-4))

How much energy in radiated per minute from the filament of an incandescent lamp at 3000 K, if the surface area is 10^(-4)m^(2) and its emissivity is 0.4 ? Stefan's constant sigma = 5.67 xx 10^(-8) Wm^(-2)K^(-4) .