Talk:Cathode

Who wrote the "Scams" section?

Why is there a signature in the text? I propose that it be removed. --Ethan 10/01/08 —Preceding unsigned comment added by 84.109.83.232 (talk) 20:13, 10 January 2009 (UTC)

There are scams involving cathodes. But of course not all offers are scams and copper cathode is also sold ex warehouse. Buyers will however want to inspect whether that is existing product. --41.14.147.158 (talk) 22:31, 14 January 2009 (UTC)

Basic Concepts of cathodes particularly regarding CRT (Cathode Ray Tubes)

hi, just clearing up some basic concepts

anodes and cathodes are defined by their relationship between the source of the electrical energy, and the thing which receives that electrical energy. on the source of the electrical energy, the anode negative, while the cathode is positive,and on the thing which receives electrical energy the polarities are opposite. hence a discharging cell has a negative terminal anode but a cell being recharged or undergoing electrolysis has a positive terminal anode instead is this correct?

The part of the cathode ray tube is incorrect. The electrons flow off of the negnative terminal: http://electronics.howstuffworks.com/tv3.htm —Preceding unsigned comment added by 75.187.47.144 (talk) 01:11, 18 May 2008 (UTC)

Ok. As far as I can tell the Cathode-ray tube is a historical mishap, but I can't tell why. The Hall Effect (1879) unambiguously determined that electrons were the carriers of current, and the cathode ray tube was invented in 1897 (Thompson), so it's not clear to me why they would call the terminal where the electrons are coming out as the "cathode".

But, either way, the definition on this page (cathode = positive (conventional) current out (neg in), anode = positive in (neg out)) works for everything except for CRTs. Circuit diagrams (physics), electronics, galvonic cells (chemistry), electrolytic cells (chemistry), all seem to be fine with this definition. As for the CRTs, it would be nice if a historian could help fill us in on this, but you'll just have to chalk this up to a historical accident, because every page (including the wikipedia page on cahode rays/CRTs) say that the cathode is where the electrons current comes out. —Preceding unsigned comment added by 75.187.47.144 (talk) 01:57, 18 May 2008 (UTC)

Tried to clarify the CRT item a bit. Better like this?

* In a cathode ray tube, it is the negative terminal where electrons flow in from the wiring and leave for the tube's near vacuum. So from the outside, positive current flows out of the device.

--Rubik's Cube (talk) 18:31, 8 September 2008 (UTC)

Yeah that makes sense to me though I may not have fully understood the complexities under discussion.

62.49.4.186 (talk) 18:27, 18 March 2009 (UTC)

Current does not flow

The "substance" that flows in wires and electrolytes is not "current", it is "charge". Current is defined as a flux of charges, so, saying that "current flows" is like saying that "the flux flows", or calling "current" the substance that flows in a river, instead of "water". Devil Master (talk) 22:33, 31 January 2009 (UTC)

I agree but it's not frowned upon to say "The tide has turned and the current is now flowing into the bay." Maybe you shouldn't and you should only say the water is now flowing in but it's a minor point anyway.

62.49.4.186 (talk) 18:27, 18 March 2009 (UTC)