# Gasiorowicz (3rd Edition), Chapter 01, Problem 01

## Problem 01. The relation between energy density and emissivity

##### The problem asks you to
`prove the relation between the energy density in a cavity and the emissive power (Equation 1-1).`
##### The problem provides (assumes)
`isotropic radiation`
```1) the definition about the energy density and the emissive power
` `
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