Stefan boltzmans apparatus:
The stefan boltzmann constant is an important constant in heat transfer. The apparatus determines stefan boltzmann constant. The apparatus consists of a hemisphere surrounded by hot water. Hot water is obtained from a water-heating tank. When the blackened disc is inserted at the center of hemisphere, heat is transferred into the disc from hemisphere by radiation and its temperature begins to rise, and from temperature raise rate. (it is measured at the intervals of 5 sec.) Stefan boltzmann constant is
A technical manual accompanies the unit.