# Distance between electrons in electron beam?

1. Jun 6, 2005

### rob5

What is the average distance between electrons in an electron beam such as produced in a cathode ray tube as they pass through the slit and then as they pass through the charged horizontal plates and magnetic coils etc that produce the deflection?

2. Jun 6, 2005

### inha

Well one can approximate the spacing but more info is needed for that. The geometry and intensity of the beam would have to be known.

3. Jun 6, 2005

### rob5

What is the formula? reference?

4. Jun 7, 2005

### shyboy

It can be figured out. If you know the beam's intensity (impulse) and the electron's velocity, you know how many electrons you have in the beam. If you know beam size, you can calcuylate the average interelectron difference.

5. Jun 7, 2005

### rob5

Of course. The question then is what is an example of a typical beam size or number of electrons generated by a tungsten filament at a typical temperature associated with a specific current and pulled toward the plate containing the slit, say 10kV relative to the voltage at the filament, emerging through a slit of a typical size say of cross section area A? And then what is the density of electrons in the beam entering and emerging from this slit and the average velocity of the electrons as they pass through the slit?