A white-hot metal wire at 3000 K has a radius of 0.075 cm. Calculate the rate per unit length at which it emits radiation if its emissivity is 0.35. Ignore the radiation it receives from the surroundings. Take Stefan'sconstant `sigma=5.7xx10^(-8)W//m^(2)K.`

The wavelength of maximum intensity of radiation emitted by a star is 289.8 nm . The radiation intensity for the star is : (Stefan’s constant 5.67 xx 10^(-8)Wm^(-2)K^(-4) , constant b = 2898 mu m K )-

The wavelength of maximum intensity of radiation emitted by a star is 289.8 nm . The radiation intensity for the star is : (Stefan’s constant 5.67 xx 10^(-8)Wm^(-2)K^(-4) , constant b = 2898 mu m K )-

The temperature of the tungsten filament of a 60 W electric bulb is T= 2000 K. Find the surface area ofthe filament. The emmissivity of the surface is e= 0.30. Neglect radiation received from surrounding. Take sigma=5.7xx10^(-8)w//M^(2)k.

A 500W lamp loses all of its energy by emission of radiation from the surface. If the area of the surface of the filament is 2.0cm^(2) and its emissivity is 0.5, estimate the temperature of its filameiit. Given that Stefan constant, sigma =5.7xx10^(-8)W//m^(2)K^(4). Neglect radiation receivedby lamp from surrounding.

A 100 watt filament loses all its power by radiation when it is heated to a temperature of 2500 K. If the diameter of the filament is 0.2 mm and the surface emissivity of the filament is 0.5, find the length of the filament. (Stefan's constant sigma = 5.67 xx10^-8 W/m^2k^4 )

What is the temperature at which a black body radiates heat at the rate of one kilowatt per unit area ? (Stefan 's constant sigma = 5.7 xx 10^(-8) S.Iunits)

Calculate the temperature at which a perfect black body radiates at the rate of 1 W cm^(-2) , value of Stefan's constant, sigma = 5.67 xx 10^(-5) W m^(-2) K^(-8)

Calculate the temperature at which a perfect black body radiates at the rate of 1 W cm^(-2) , value of Stefan's constant, sigma = 5.67 xx 10^(-5) W m^(-2) K^(-8)

Calculate the temperature at which a perfect black body radiates at the rate of 1 W cm^(-2) , value of Stefan's constant, sigma = 5.67 xx 10^(-8) W m^(-2)K^(-4)

A hot body at 800^@C is radiating 500 J of energy per minute. Calculate the surface area of the body if emissivity is 0.23 and Stefan's constant is 5.67 xx 10^(-8) Wm^(-2) K^(.-4) .