A solid metal sphere of radius is heated uniformly to and is then allowed to radiate…

PHYSICS · Multi-part · CBSE · Physics · Thermal Properties of Matter · Thermal Properties of Matter

Problem

A solid metal sphere of radius

2.0\,\text{cm}

is heated uniformly to

800\,\text{K}

and is then allowed to radiate energy into a large evacuated enclosure whose walls are at a much lower temperature that may be taken as

0\,\text{K}

for this calculation. Take the sphere to behave as an ideal absorber. Use

\sigma = 5.67\times10^{-8}\,\text{W\,m}^{-2}\,\text{K}^{-4}

. (i) Calculate the surface area of the sphere. (ii) Determine the total power radiated by the sphere at

800\,\text{K}