Naked Science Forum

Non Life Sciences => Physics, Astronomy & Cosmology => Topic started by: mcjhn on 17/02/2011 12:24:14

Title: why does an electron beam in a cathode ray tube look blue?
Post by: mcjhn on 17/02/2011 12:24:14

thanks!

Title: why does an electron beam in a cathode ray tube look blue?
Post by: graham.d on 17/02/2011 13:39:54

It shouldn't I think. You should not be able to see the beam at all unless there is some contaminating gas in the tube.

Title: why does an electron beam in a cathode ray tube look blue?
Post by: bardman on 17/02/2011 17:55:00

You are probably not dealing with simply a vacuum tube. You are probably dealing with the ionization of gas in a tube. I would have to do research to determine which gas produces blue light. However, that is probably what is happening.

Title: why does an electron beam in a cathode ray tube look blue?
Post by: bardman on 17/02/2011 18:13:28

I think you may have been looking at a krypton filled tube. Check out the link http://www.chemicool.com/elements/krypton.html (http://www.chemicool.com/elements/krypton.html)

Also look up discharge tube or Geissler tube.