Electron beam hitting a metal plate

[abdo799]

So i have this simple situation where i have an electron beam with a certain kinetic energy, and i have a metal plate connected to the ground, and the electrons hit the plate, now i want to know the voltage of the current in the wire to the ground. Now i know both kinetic energy of the electrons and the current so if the energy of a current is V*I*t and the energy we can get from a certain number or electrons is N*Ke where N is the number of electrons is N and Ke is the kinetic energy , this gives us V=Ke but i don't know if that's right, so if it's wrong , what's the right answer ?

 

[davenn]

So i have this simple situation where i have an electron beam with a certain kinetic energy, and i have a metal plate connected to the ground, and the electrons hit the plate, now i want to know the voltage of the current in the wire to the ground.

I would expect it to be zero because it's connected to ground

depending on the energy of the electrons, there's a higher chance of X-rays being produced

 

[abdo799]

I would expect it to be zero because it's connected to ground

depending on the energy of the electrons, there's a higher chance of X-rays being produced

what if the electrons don't have enough energy to produce x-rays

 

[nasu]

They won't produce them. But this doesn't change the answer. I thing davenn mentioned x-rays as a side aspects.

 

[davenn]

They won't produce them. But this doesn't change the answer. I thing davenn mentioned x-rays as a side aspects.

indeed :)

what if the electrons don't have enough energy to produce x-rays

then they just go straight to ground

 

[abdo799]

indeed :)
then they just go straight to ground

i did some research about that and i have 1 last question, can they produce gamma rays if the kinetic energy is really high or it has a limit to the energy of photon produced and the rest becomes heat, i personally think it's the second choice, but i am always wrong , so what do you think?

 

[davenn]

Now I'm not a particle physicist OK ( those in the field may chime in with additional info)

putting aside astronomical sources of Gamma rays ... stars, black holes etc

on earth, Gamma rays are produced in the natural radioactive decay process, along with Alpha and Beta particles
would be the principle source. a secondary source is produced by firing Gamma rays at a atom where you can get an electron-positron annihilation
which results in the release of Gamma rays
( I personally don't want to go deeper than that without getting out of my depth very quickly )

Dave

 

[Drakkith]

i did some research about that and i have 1 last question, can they produce gamma rays if the kinetic energy is really high or it has a limit to the energy of photon produced and the rest becomes heat, i personally think it's the second choice, but i am always wrong , so what do you think?

Yes, electrons fired into a stationary target are used to produce EM radiation of up to 25 MeV, if not more. Note that since this radiation isn't produced by the decay of an atomic nucleus it would probably be classified as high energy X-rays, not gamma rays. The distinction between the two is that gamma radiation is usually defined to be EM radiation produced by the decay of an atomic nucleus, regardless of the energy of the radiation. A notable exception is in astronomy, where the two are defined according to their energy.

To quote wiki: https://en.wikipedia.org/wiki/Gamma_ray

The distinction between X-rays and gamma rays has changed in recent decades. Originally, the electromagnetic radiation emitted by X-ray tubes almost invariably had a longer wavelength than the radiation (gamma rays) emitted by radioactive nuclei.[6]Older literature distinguished between X- and gamma radiation on the basis of wavelength, with radiation shorter than some arbitrary wavelength, such as 10−11 m, defined as gamma rays.[7] However, with artificial sources now able to duplicate any electromagnetic radiation that originates in the nucleus, as well as far higher energies, the wavelengths characteristic of radioactive gamma ray sources vs. other types, now completely overlap. Thus, gamma rays are now usually distinguished by their origin: X-rays are emitted by definition by electrons outside the nucleus, while gamma rays are emitted by the nucleus.[6][8][9][10] Exceptions to this convention occur in astronomy, where gamma decay is seen in the afterglow of certain supernovas, but other high energy processes known to involve other than radioactive decay are still classed as sources of gamma radiation.

 

[ZapperZ]

Wow. This thing started out being quite simple, and has turned into a radiation-generating device!

To the OP: you may want to look at an instrument called the Faraday Cup. And yes, you can measure the amount of charge that hit the metal plate, in principle. This instrument is used in many accelerator beamline as an alternative to the ICT (integrated charge transformer) to measure the amount of charge in a bunch. The physics of it is rather easy to follow. Of course, to make a low-noise, high time-resolution device will require a lot of other things, but the principle is the same.

Zz.