plasma ball in the microwave

[the guy]

about the experiment in which a 'plasma ball' or 'ball lightning' or 'plasma cloud', or whatever you wish to call it, is produced in a microwave oven by sticking a rod of carbon vertically inside the oven. (which, i would like you to know, i am not about to repeat for the sake of my microwave oven and myself)

i have a few questions

 

1. is the 'cloud' of plasma negatively or positively charged, or neither?

 

2. why does it go upwards?

if you stuck it to the wall of the oven sticking horizontally inwards would it still go up or would it shoot across?

 

3. is it hot? if so how hot?

 

4. also, does it have to be a rod?

[swansont]

Probably negatively charged, i.e. electrons, and it rises because it's hot. You can use a carbon mesh.

 

 

You can even do this with a grape.

 

 

Google for more examples

[the guy]

ah thank you kindly

 

also, if you used a faraday cage instead of a vase, would it also contain the ball, or would the ball pass through?

Edited June 5, 2011 by the guy