cathode rays (1 Viewer)

[peony]

does cathode rays travel in air or do they only travel in a vacuum ? thanks

 

[asdf]

vacuum. However there can be a small percentage of air in vacuum too.

 

[Ragerunner]

In vacuum.

Originally posted by asdf
vacuum. However there can be a small percentage of air in vacuum too.

That is true. The amount of air can also make a noticable difference in the result of the ray when switched on.

 

[inasero]

only in a vacuum.....if they emanate in a non vacuum (normal air) then they are stopped very quickly due to collisions and loss of kinetic energy

 

[abdooooo!!!]

electrons travel best in total vacuum... electrons are very light and have a negative charge, and so they feel strong forces when they travel past gas molecules. so whenever an electron comes close to a gas molecule, it would be bent off course. this would make the so called "cathode ray" to be scattered...

does anyone know whether this difference in potentials produced by the electrodes allow for postive charged particles to flow backwards ie in opposite direction of the of the electrons? and what might be the effect of this if it does happen?

thanks

 

[zeropoint]

If you generate electrons in a cathode ray tube you will find that positive electrons (positrons) are emitted in the opposite direction relative to the electrons.

 

[abdooooo!!!]

but what would be the effect of this? isn't there also positively charged air particles that will also migrate against the electron current?

 

[victorling]

Originally posted by peony
does cathode rays travel in air or do they only travel in a vacuum ? thanks

CATHODE RAY travels in air with very low density and vacuum
A specially designed pump can be used to drain the air out of a container
As air pressure decreases, the striations decrease in number and eventually have only the anode and the cathode emitting light
The ray seems to be emitted from the cathode, as it is observed to be that there is light at the anode, thats why it is named "cathode ray"

 

[Affinity]

Originally posted by zeropoint
If you generate electrons in a cathode ray tube you will find that positive electrons (positrons) are emitted in the opposite direction relative to the electrons.

There's almost no positrons in a CRT unless you introduce it.

canal rays are positive particles moving from anode to cathode, they are not electrons/positrons