# Boltzmann Constant

First of all, there are constants named after Ludwig Boltzmann, first Boltzmann constant and the second Stefan-Boltzmann constant. We will discuss the first one here.

Both Boltzmann constants play vital roles in Physics and Astronomy.

## Role of Boltzmann Constant in Physics

**Boltzmann Constant** unites the macroscopic and microscopic worlds, and provides the basis for the zeroth law of thermodynamics.

**Zeroth Law of Thermodynamics**

If you could ‘look inside’ an isolated system (in equilibrium), the **proportion of constituents in the system with energy E** is a function of **E**, and the **Boltzmann constant** (*k* or *k _{B}*).

- The proportion of constituents in the system with energy E is proportional to e
^{-E/kT}. - Here T is the temperature in Kelvin.
*k*is Boltzmann’s constant and k=1.38×10^{-23}Joules per Kelvin.

## Frequently Asked Questions

## Who was Ludwig Boltzmann?

Ludwig Eduard Boltzmann was an Austrian physicist and philosopher.

## What is the value of Boltzmann Constant?

The value of Boltzmann Constant k is 1.38×10^{-23} Joules per Kelvin.