Two spheres P and Q of same colour having radii 8 cm and 2 cm are maintained at temperatures 127°𝐶  and 527°𝐶  respectively. The ratio of energy radiated by P and Q is

A sphere of radius R has an absolute temperature T and it radiates power P. A second sphere has a radius 2R. The spheres can be assumed to be black-body radiators. Determine: a. the power radiated by the second sphere, when its absolute temperature is T b. the absolute temperature of the second sphere, when it radiates power P

A spherical body of area A and emissivity e=0.6 is kept inside a perfectly black body. Energy radiated per second by the body at temperature T is

A sphere of metal with emissivity 0.8360.836 is at temperature 297.0 ∘C297.0 ∘C in an environment with 16.5 ∘C.16.5 ∘C. The sphere has a radius 59.1 cm.59.1 cm..

A sphere with emissivity 0.613 and radius of 0.841 m has a temperature of 58.7°C. If the sphere is placed inside an environment at temperature 89.2°C, what is the net rate of energy exchange? Calculate the power of absorption and subtract the power of radiation to give the net power. Use Watts (W) as your unit and give the unit.

7-An object at 27°C has its temperature increased to 37°C. Thepower then radiated by this object increases by how manypercent?a.3.3b.14c.37d.253ANS: B