Szczepan Bialek wrote:

napisa? w wiadomo?ci
...
Szczepan Bialek wrote:

What the sparks are made of?

Electrons liberated by the HIGH VOLTAGE, idiot.

Is it the field electron emission?
S*

No.

Read this:

http://en.wikipedia.org/wiki/Field_electron_emission

Read all of it.

Then read it again until you understand it.

After you have mastered that, read this:

http://en.wikipedia.org/wiki/Corona_discharge

Read all of it.

Then read it again until you understand it.

After you have mastered that, read this:

http://en.wikipedia.org/wiki/Electric_arc

Read all of it.

Then read it again until you understand it.

If you can get this far, your question has been answered fully.