Massachusetts Institute of Technology
Sign in Create Account

Breakdown of Air

Grounding rod tips of different sizes are used to discharge a large Van de Graaff generator. The larger the curvature of the tip, the more charge must build up to break down the air, resulting in longer sparks. The electricity ionizes air molecules, releasing quick flashes of light.

A pointed tip barely sparks at all, but instead creates an electric field so strong that it forms a tiny ball of plasma just beyond the tip. This is known as "St. Elmo's Fire", and is just visible when all the lights are turned off.

Comments (0)

It looks like no one has posted a comment yet. You can be the first!

You need to log in, in order to post comments. If you don’t have an account yet, sign up now!

MIT Department of Physics Technical Services Group

MIT Department of Physics Technical Services Group

Category: Science | Updated almost 2 years ago

Created
March 03, 2010 12:42
Category
Tags
License
Creative Commons Attribution-NonCommercial (What is this?)
Additional Files


Viewed
33069 times

More from MIT Department of Physics Technical Services Group

MIT Physics Demo -- Levitating Magnet

MIT Physics Demo -- Levitating Magnet

Added almost 7 years ago | 00:00:47 | 41662 views

MIT Physics Demo -- Galvanometer Principle

MIT Physics Demo -- Galvanometer Pr...

Added almost 7 years ago | 00:00:47 | 49788 views

Coupled Air Carts

Coupled Air Carts

Added almost 6 years ago | 00:07:38 | 50075 views

Hinged Stick and a Falling Ball

Hinged Stick and a Falling Ball

Added over 4 years ago | 00:01:23 | 20228 views

MIT Physics Demo -- Microwave Interference

MIT Physics Demo -- Microwave Inter...

Added 7 years ago | 00:02:11 | 27816 views

Spray Paint Oscillator

Spray Paint Oscillator

Added over 6 years ago | 00:00:51 | 28161 views