48 Pages

## General InfoEdit

### WhatEdit

The Kevin-Helmholtz timescale describes how long a star can continue to output a constant luminosity based on the energy it radiates away from gravitational collapse.

### DefinitionEdit

$t_\textrm{KH} = \frac {\Delta E_g}{L}$

### NotesEdit

• We can determine $\Delta E_g$ by using the Virial Theorem to determine the initial and final energies of the star based on its initial and final radii