The surface of a black body is at a tempera ture `727^(@)C` and its cross section is `1m^(2)` Heat radi ated from this surface in one minute in Joules is (Stefan's constant `=5.7 xx 10^(-8) W//m^(2)//k^(4))` .

The surface of a black body is at a temperature 727^(@)C and its cross section is 1m^(2) Heat radiated from this surface in one minute in Joules is (Stefan's constant =5.7 xx 10^(-8) W//m^(2)//k^(4)) .

The surface of a black body is at a temperature 727^(@)C and its cross-section is 1 m^(2) . Heat radiated from this surface in one minute in joules is (Stefan's constant = 5.7 xx 10^(-8) W//m^(2) // k^(4) )

Assuming a filament in a 100W light bulb acts like a perfect blackbody, what is the temperature of the hottest portion of the filament if it has a surface area of 6.3 xx 10^(-5) m^(2) ? The Stefan-Boltzmann constant is 5.67 xx 10^(-8) W //(m^(2).K^(2)) .

A body which has a surface area 5.00 cm^(2) and a temperature of 727^(@)C radiated 300 j of energy each minute. What is the emissivity of body? Steafan's constant =5.67xx10^(-8) Wm^(-2) K^(-4) .

A metallic sphere having radius 0.08 m and mass m = 10 kg is heated to a temperature of 227^(@)C and suspended inside a box whose walls ae at a temperature of 27^(@)C . The maximum rate at which its temperature will fall is:- (Take e =1 , Stefan's constant sigma = 5.8 xx 10^(-8) W//m^(-2)K^(-4) and specific heat of the metal s = 90 cal//kg//deg J = 4.2 "Joules"//"Calorie")

A metallic sphere having radius 0.08 m and mass m = 10 kg is heated to a temperature of 227^(@)C and suspended inside a box whose walls ae at a temperature of 27^(@)C . The maximum rate at which its temperature will fall is:- (Take e =1 , Stefan's constant sigma = 5.8 xx 10^(-8) W//m^(-2)K^(-4) and specific heat of the metal s = 90 cal//kg//deg J = 4.2 "Joules"//"Calorie")

A metallic sphere having radius 0.08 m and mass m = 10 kg is heated to a temperature of 227^(@)C and suspended inside a box whose walls ae at a temperature of 27^(@)C . The maximum rate at which its temperature will fall is:- (Take e =1 , Stefan's constant sigma = 5.8 xx 10^(-8) W//m^(-2)K^(-4) and specific heat of the metal s = 90 cal//kg//deg J = 4.2 "Joules"//"Calorie")

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)

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.