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 over 1 year ago

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


Viewed
31525 times

More from MIT Department of Physics Technical Services Group

The Coriolis Effect

The Coriolis Effect

Added 5 years ago | 00:03:00 | 76423 views

Fire Extinguisher on a Tricycle

Fire Extinguisher on a Tricycle

Added almost 6 years ago | 00:00:53 | 36591 views

Physics Demo -- Jumping Ring

Physics Demo -- Jumping Ring

Added over 6 years ago | 00:01:40 | 46465 views

Lenz's Law with Copper Pipe

Lenz's Law with Copper Pipe

Added over 2 years ago | 00:01:38 | 5974 views

Michelson Interferometer

Michelson Interferometer

Added almost 4 years ago | 00:04:06 | 19070 views

Laser Diffraction and Interference

Laser Diffraction and Interference

Added over 5 years ago | 00:02:25 | 36407 views