The temperature and the surface area of the body are `227^(@)C` and `0.15 m` respectively. If its transmitting power is negligible and reflecting power is `0.5`, then calculate the thermal power of the body.
(Given `sigma-5.67xx10^(-4)J//m^(2)//s//K`)

If reflecting and transmitting powers of a body are 0.2 and 0.3 units, then its Absorptive power will be

A filament of an evacuated light blue has length 10 cm, diameter 0.2mm and emissivity 0.2. Calculate the power it radiates at 2000 K ( sigma=5.67xx10^-8 J/m^2k^4 )

A black body of mass .0.10 g is kept in a black enclosure or temperature 27^(@) C. The temperature of the body is 127^(@) C and the area of the emittimg surface in 10^(-3) m^(2) . If its specific heat capacity is 420 J kg^(-1)k^(-1) find the rate of cooling of the body . sigma = 5.67xx10^(-8)Wm^(-2)K^(-4) .

Assume that the total surface area of a human body is 1-6m^(2) and that it radiates like an ideal radiator. Calculate the amount of energy radiates per second by the body if the body temperature is 37^(@)C . Stefan contant sigma is 6.0xx10^(-s)Wm^(-2)K^(-4) .

A metal ball of surface area 200 cm^(2) and temperature 527^(@)C is surrounded by a vessel at 27^(@)C . If the emissivity of the metal is 0.4, then the rate of loss of heat from the ball is (sigma = 5.67 xx10^(-8)J//m^(2)-s-k^(4))