The Stefan-Boltzmann law indicates that the energy emitted per second per area of an emitting surface varies with the fourth power of the Kelvin temperature. Suppose the center of a granule on the Sun's photosphere is 6000 K and the edges of the cell are 100 K cooler. About how much energy is emitted each second from each unit area on the edge compared with that from the center?

Question

Quizplus · Accepted Answer

The Stefan-Boltzmann law states that the energy emitted per unit area is proportional to the fourth power of the temperature (T) in Kelvin. If the center of a granule is at 6000 K, and the edges are 100 K cooler (5900 K), then the ratio of energy emitted from the edge to that from the center is (5900/6000)^4. This calculation gives a value close to 0.93, or 93%, indicating that the edges emit about 93% of the energy per unit area compared to the center.

The Stefan-Boltzmann Law Indicates That the Energy Emitted Per Second