Vacuum Jump

  • Thread starter mcjosep
  • Start date
  • #1
35
0

Main Question or Discussion Point

Is it possible for electricity to jump a vacuum gap? If so, what is it called when that happens?
 

Answers and Replies

  • #2
595
0
Yes. Otherwise those old Fleming tubes wouldn't work...
Arching or conduction depending on the amount of current and suddenness of onset.
It takes more voltage to get it going since air and moisture make better conduction paths. I seem to remember 30Kv/inch for an electrical arc in a vacuum, but I could be way off.
 
  • #3
mathman
Science Advisor
7,840
440
Before transistors, radio and TV sets used vacuum tubes, which are based on electron flow.
 
  • #4
4,662
5
Is it possible for electricity to jump a vacuum gap? If so, what is it called when that happens?
In vacuum tubes, the electron current is called thermionic emission and plate current. The current is not visible, but the plates sometimes turn red hot.

With very high electric field gradients in very vacuum, field emission of electrons is possible, with lots of x-rays as the accelerated electrons hit the other side.

Bob S
 

Related Threads on Vacuum Jump

  • Last Post
Replies
4
Views
2K
Replies
50
Views
4K
  • Last Post
Replies
1
Views
2K
  • Last Post
Replies
6
Views
3K
  • Last Post
Replies
7
Views
5K
  • Last Post
Replies
2
Views
1K
  • Last Post
Replies
4
Views
2K
  • Last Post
Replies
15
Views
13K
  • Poll
  • Last Post
2
Replies
31
Views
16K
  • Last Post
Replies
1
Views
6K
Top