How are cathode rays and anode rays formed?

Question

Can you please explain how cathode rays and anode rays are formed withing a Crookes tube or cathode ray tube?

Answer 1

Cathode rays are just electrons ejected from a cathode that is usually by thermal excitement.. The electrons are then accellerated through a potential difference and then deflected by mutually perpendicular electric fields that have varying voltages applied to them.



When the electron hits the phosphor coated glass of the cathode ray tube it produces light.



...



the anode rays are XRAYS i think



They are just electrons thermally excited off the cathode again.. but this time they are accellerated many times faster than cathode rays..



when they hit the anodes they have so much kinetic energy the electrons just pass by the atom of the metal anode .. but they experience whats called BREMSSTRAHLUNG effect which is german for braking radiation.. The electron is slowed by the massive nucleus of the anode metal so it looses kinetic energy ..

but usually keeps going till it hits another atom and keep loosing kinetic energy till it has none..



That explains why xrays come in continuous wavelengths ...



When the electron slows down a PHOTON of xray is released ...



1 A or less in wavelength



Lamdamax = hc/eV



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





hope that helps..

3rd year physics major.

Answer 2

Production Of Cathode Rays

Answer 3

A perforated cathode is used for canal rays as the positive ions, seemingly protons are much heavier than electrons. Both the electrons and protons cannot pass through the cathode nor anode, but the electrons get scattered easily due to their charge and their lightness and hence produce fluorescence, while the positively charged ions usually gets absorbed. Hence a perforated cathode is used for canal rays so that they can pass through the holes to strike the walls of the tube producing fluorescence. This is my opinion. -Asif Nasser Student @ lecole Chempaka