Speed Of Charged Particles - Everything Else - Corolland: the Toyota Corolla Forums

I have a physics question.

Lets say that an electric field is constant and exists between two plates. And then you have a few charges: +q, +2q, -q that leak through the plates and into the electric field that exists between two plates. Does the speed of the particles increase, decrease, or remain the same in the region between the plates?

I figured it would be the same because of Newton's second law = equal and opposite. I don't know for sure though.

please keep answers to 1-2 paragraphs. I just need a concise answer. Yea, I'm talking to you contour, lol!

1,424 posts

I have a physics question.
Lets say that an electric field is constant and exists between two plates. And then you have a few charges: +q, +2q, -q that leak through the plates and into the electric field that exists between two plates. Does the speed of the particles increase, decrease, or remain the same in the region between the plates?
I figured it would be the same because of Newton's second law = equal and opposite. I don't know for sure though.
please keep answers to 1-2 paragraphs. I just need a concise answer. Yea, I'm talking to you contour, lol!

I don't even need 1 or 2 paragraphs.

Of course charged particles that enter an electrical field are going to move and since the electrical field is acting on them.

If the electrical field and particles are of like charge, the particles will slow down due to repulsive forces. If the field and particles are of opposite charge the particles will speed up due to attractive forces.

If the above facts weren't true you couldn't have electron guns in televisions or charge storing devices in electronics.

Bikeman982

But how do the particles feel about being in the electrical field??

That's right. I forgot about that, if particles enter the field depending on their charge, they will slow or speed.

However, what if the test charges were just teleported to the magnetic field? Would the +2q experience a greater velocity than the +q charge?

Bikeman982

That's right. I forgot about that, if particles enter the field depending on their charge, they will slow or speed.
However, what if the test charges were just teleported to the magnetic field? Would the +2q experience a greater velocity than the +q charge?

When was the last time you teleported particles into an electric field?

That's right. I forgot about that, if particles enter the field depending on their charge, they will slow or speed.
However, what if the test charges were just teleported to the magnetic field? Would the +2q experience a greater velocity than the +q charge?
When was the last time you teleported particles into an electric field?

Ok.......

bikeman........

...... um ......................I don't think your understanding me.

I'm asking if the strength of the test charges placed in a constant electric field would result in varying velocity (whether it is attractive or repulsive)

This is a pretty broad question - can be answered many different ways. Need to define some boundary conditions and what are you looking at, ie. Electrostatics, Electromagnetics, constant E field, constant B field, etc. I'm a Physicist, if that matters.

Electrostatics are easy to generalize as they have a very strong parallels to gravity. Once you throw in motion, then you have a time-varying fields. Because these test charges will generate their own E-field and in turn, because they are moving, will generate a B-field as well. The transistion in which electric or magnetic fields change in time is no longer electrostatics, but now you have electromagnetics. Since you mentioned electric field initially and then added magnetic field later - I'll take it as a electromagnetic case and charged particles that are injected, teleported, or leaked into the fields.

You can describe the forces exerted onto the charged particles as Lorentz Force. There will be a force component from the electric field (qE) and from the magnetic field (qv x B ), which together is in the form of F = q(E + v x B ).

Use dimensional analysis (just looking at the units) - you can see that doubling the test charge from a +q to a +2q and assuming that the E and B fields are constant, the net force constant - your velocity for the larger charge would be lower than the velocity of the smaller charge.

As for teleporting particles - they have recently done that with photons in several experiments. IBM researched this some years ago and have generated publications on quantum teleportation and the possiblilties if you take into account the Einstein Podolsky Rosen (EPR) paradox. Sounds a little far fetched and straight from an episode of Star Trek - but it is real.

Bikeman982

What will happen to the transportation industry (planes, trains, and automobiles) when we can teleport??

Still be there - you'll have the usual mix of early adopters of the technology and ones that will not touch it with a 10' pole. Same deal with the introduction of digital media to audio/video production. Some embraced it - others still prefer film or analog tapes. Last time I checked - you could still buy VHS units, blank and prerecorded media, still buy cassette tapes, 35mm film, and floppy drives. As long as people still use them, they will still support those infrastructures.

Bikeman982

Still be there - you'll have the usual mix of early adopters of the technology and ones that will not touch it with a 10' pole. Same deal with the introduction of digital media to audio/video production. Some embraced it - others still prefer film or analog tapes. Last time I checked - you could still buy VHS units, blank and prerecorded media, still buy cassette tapes, 35mm film, and floppy drives. As long as people still use them, they will still support those infrastructures.

Probably not to the same extent - quantity wise.

What about Beta tapes - extinct.

I still use VHS and cassettes myself. I guess I am a diehard.

Speaking of Beta - I still use my Sony Betamax every once and a while, still works well - can't really run to a Best Buy or Circuit City to buy Beta tapes but they still make them - just have to order them. Picked up some 3M ones and some Kodak ones (brand new media ) last year for $2.50 a piece.

This is a pretty broad question - can be answered many different ways. Need to define some boundary conditions and what are you looking at, ie. Electrostatics, Electromagnetics, constant E field, constant B field, etc. I'm a Physicist, if that matters.
Electrostatics are easy to generalize as they have a very strong parallels to gravity. Once you throw in motion, then you have a time-varying fields. Because these test charges will generate their own E-field and in turn, because they are moving, will generate a B-field as well. The transistion in which electric or magnetic fields change in time is no longer electrostatics, but now you have electromagnetics. Since you mentioned electric field initially and then added magnetic field later - I'll take it as a electromagnetic case and charged particles that are injected, teleported, or leaked into the fields.
You can describe the forces exerted onto the charged particles as Lorentz Force. There will be a force component from the electric field (qE) and from the magnetic field (qv x B ), which together is in the form of F = q(E + v x B ).
Use dimensional analysis (just looking at the units) - you can see that doubling the test charge from a +q to a +2q and assuming that the E and B fields are constant, the net force constant - your velocity for the larger charge would be lower than the velocity of the smaller charge.

I don't understand how a bigger charge would move slower than its smaller counterpart. Lets say that you have a plane with a positive charge +q evenly dispersed throughout the plane. And then place a +q and a +2q test charge near the plane. Both of which are spaced evenly away from the plane. Mind you the two test charges don't interact, they are observed as separate tests.

Which test charge will experience a greater repulsive force?

Bikeman982

Speaking of Beta - I still use my Sony Betamax every once and a while, still works well - can't really run to a Best Buy or Circuit City to buy Beta tapes but they still make them - just have to order them. Picked up some 3M ones and some Kodak ones (brand new media ) last year for $2.50 a piece.

You still have one?? That's rare. I am wondering when VHS will become obsolete.

Everybody is going to DVD and CD's.

I also have a large cassette collection and never want them to "phase out".

Most new cars today have CD players and not cassette.

I don't understand how a bigger charge would move slower than its smaller counterpart. Lets say that you have a plane with a positive charge +q evenly dispersed throughout the plane. And then place a +q and a +2q test charge near the plane. Both of which are spaced evenly away from the plane. Mind you the two test charges don't interact, they are observed as separate tests. Which test charge will experience a greater repulsive force?

You've changed the question slightly for this case. Here - you have a test charged (static charged) and you use them to probe the nature of the electric field generated by the charged plate. You can use Coulomb's law to describe this, where F = qE. Just from the equation - the force exerted on to the charged particle is proportional to the amount of charge, ie. the greater the charge, greater force exerted on it. But we are not describing any motion here - nothing dynamic yet.