Objective: Verify that intensity of radiation is proportional to the fourth power of the temperature, T4
The way that intensity of radiation from a black body depends on temperature is described by the
Stefan-Boltzmann law. Similar dependence on temperature is exhibited by the intensity of radiation
from an incandescent lamp with a tungsten filament. In this experiment, a Moll thermopile is used to
make a relative measurement which verifies the law. The temperature of the filament can be determined
from the way its resistance depends on temperature, which can be determined very accurately
using a four-wire method.