# What is Paschen minimum?

## What is Paschen minimum?

For a 7.5 μm gap the arc voltage is 327 V, which is 43 MV/m. This is about 14 times greater than the field strength for the 1.5-metre gap. The phenomenon is well verified experimentally and is referred to as the Paschen minimum.

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**What is Paschen’s Law in High voltage studies?**

Paschen’s law describes the characteristics of gas breakdown voltage between two electrodes. This law states that the Gas breakdown voltage(VB) depends only on the product of gas pressure (p) and gap length(d) between electrodes (VB=f(pd)).

### What is the Paschen minimum?

The phenomenon is well verified experimentally and is referred to as the Paschen minimum. The equation loses accuracy for gaps under about 10 μm in air at one atmosphere and incorrectly predicts an infinite arc voltage at a gap of about 2.7 micrometres.

**What is the formula for Paschen breakdown?**

In order to account for the effect of temperature, the Paschen Breakdown is generally stated as V = f (Nd), where N is the density of the gas molecules. This is necessary, because the pressure of the gas changes with temperature according to the gas law pν = NRT, where ν is the volume of the gas, T is the temperature, and R is a constant.

## What is the significance of the Paschen principle?

It is named after Friedrich Paschen who discovered it empirically in 1889. Paschen studied the breakdown voltage of various gases between parallel metal plates as the gas pressure and gap distance were varied:

**What is the Paschen minimum for an arc voltage?**

This is about 14 times greater than the field strength for the 1.5-metre gap. The phenomenon is well verified experimentally and is referred to as the Paschen minimum. The equation loses accuracy for gaps under about 10 μm in air at one atmosphere and incorrectly predicts an infinite arc voltage at a gap of about 2.7 micrometres.