Curving of Charged Particles through a Magnetic Field?

X
what is the X in the equation because that could be the velocity flow number count.It could also be that it controls the velocity in a control direction.

right or wrong, the X is the vector cross product. It is the famous right hand rule.

lVlr, excellent question. Soon you will learn of the duality between electricity and magnetism as sinusoidal components of a plane wave. Electricity produces magnetism, and magnetism produces electricity...magnetism is produced from electricity when combined with the Lorentz contraction of space and time predicted by Einstein's theory of relativity, as I recall. It has something to do with the way in which these field effects are propagated that creates a rotation...and it is probably somehow the result of photon and electron spin, which is part of quantum theory that you may touch upon at the end of the course

Thanks.
Yes I used X for the Cross-Product (I should have explained that, du!)

I could definitely under stand that it has something to do with the way the two magnetic fields effect eachother.

But I don't understand a Photon spin? Are you saying there is always light generated at least when a charged particle is passing through a magnetic field?

Oh, I don't expect you to understand photon spin now! And I won't be explaining that.



Actually a charged particle is, by definition, a particle that is creating an electric field around itself. When a charge particle moves, the electric field creates a magnetic field.

Electric fields and magnetic fields are both just electromagnetic waves, and light is also an electromagnetic wave. So are radiowaves, microwaves, x-rays, etc (sound waves are not). All these electromagnetic waves are made of the same stuff - photons. So you can call any of the above light.

Photons are the mediating boson for the electromagnetic force. Every fundamental force has it's own kind of boson. Bosonic particles exist around fermi particles sort of how electrons exist around atom nucleii. It is the interaction between bosons - sharing, exchanging, that creates forces between objects. I only understand it at a superficial level.

Magnetic Field Disturbances.

Okay I guess what I'm wondering is: thinking of the Magnetic Field that is generated by a moving charge (as demonstrated by the sort of circle in my ASCII picture.) Notice how on the topside of the circle of the Generated Magnetic Field is in the opposite direction of the as the Uniform Magnetic Field drawn on either side of the circle. The notice how the bottom is in the same direction. So what I'm thinking is this opposition on one side creates a sort of torque that pulls it out to the side. Also if you use the right handed rule, where the charge is moving into the screen (as demonstrated by the X), also where the force is moving from right to left (as demonstrated by the arrows) the force on the charge should be upward, which is exactly what I hypothesized from the picture.

This is a RESULT of vxB, not an explanation for it.

bm

As my physical chemistry professor always said, "science doesn't answer why, but only how."

That is a pessimistic view. Science has answered so many questions. The fact that new answers lead to new questions just means that we don't have to become bored with our lives yet because there is still some mystery left. There is an observable limit to the knowledge that can be acquired from within any system...and we know so much, in many ways we have already hit the physical limit when the interactions are too small to be measured or to have any noticeable effect that can be studied. But that don't make it useless

Why?
Hey thanks! You've been a great, great help to me so far. Most people don't even bother or don't know enough and still try. Anyway, you've been a great help.

But, You said:


I disagree.
I had asked if the generated circular magnetic field around a moving charge in a uniform magnetic field had a relation to the curving force....

Actually come to think of it I do begin to see what your saying. But if you could could you explain a little more? Thanks a lot. You've already been a great help.

Hehe, I guess I misinterpreted your question to be much deeper than it was.

First of all, the magnetic force is not a "curving force." It acts in a single straight direction at any one time, just like gravity.

This problem is really quite similar to planetary orbits. If you put a small planet next to a massive star, they will exert equal gravitationational forces on each other. The star will accelerate very little, but the planet will accelerate in the direction of the star rapidly until it is burned up.

If, instead, the planet has some initial velocity perpendicular to the direction to the star, the acceleration due to gravity will bend the planet's path...and if there is the exact right acceleration, the path will be bent into a perfect circle around the star. Since the planet is always being accelerated, it is basically "falling in a circle forever." That's an orbit.

The situation here is almost exacty the same. Instead of a planet we have a charged particle, and instead of the sun we have the presence of a uniform magnetic field. Forces are all equal, and the force created by the magnetic field is no different than the force of gravity (technically this may not be exactly true but you will be fine if you spend the rest of your life making that simplification).

The magnetic force is always in the direction of qVxB, right? So if the magnetic field is directed into the page, and the particle initially has a velocity up, then using the right hand rule you see that the magnetic force will cause an acceleration to the left. So the particle takes a small step to the left in the direction of the acceleration, and a small step up in the direction it was already going. Then compute the direction of the magnetic force again. The magnetic force is always perpendicular to the current velocity, see? That means it will follow a curve...and if the radius of the curve is small enough that it stays within the field range, it will travel in a circle forever just like a planetary orbit.

As you can see, this curved motion is just a result of F = qV x B

I had originally assumed you were asking, "why does F = V x B?" and that is a much more difficult question.

No, no, you were thinking correctly. I understand how to mathmatically compute the qV X B, but I don't understand exactly as you said:



Sorry I mislead you with my last post.

Ok, I see what you are getting at with your diagram...no, thats wrong. First of all, the particle would be moving counterclockwise not clockwise. Secondly, forces are dependent on the present state...you are using circular logic to say that "since the particle will move in a circle, the direction of motion relative to the magnetic field will create a torque"...but that makes no sense, the only reason the particle moves in a circle is because of the torque created by the field in the first place...and also velocity and acceleration are completely irrelevant when calculating forces, because forces are only dependent on distance/position.

Thanks again.
I now understand. Don't ask me to explain but between your explainations some stuff I looked up on wikipedia and some stuff from my text book I know understand. Thanks, I doubt I would have done it without you, at elast without it taking a whole lot longer.

And what is it, exactly, that you understand? Don't tell me you've figured out why F = V x B...if you have, I'm very eager to hear it.

Not a Mathematical Proof....
Well, that's why I said don't ask me to explain it. I can't really explain this...It's just I was in Physics and the book said there's a Force qvXB it didn't make any sense to me. I aked my teacher why and she said I don't know don't question it. Of course I questioned it. I mean I never really questioned F = ma but this was just a little to weird. So I recently did a picture of the magnets effect on the alignment of the spin of molecules projected that tendancy graphically onto the induced magnetic effects by a moving particle and it all made some logical sense. Like F = ma. To the point where I was able to accept it.

I'm sorry, but no...your explanation is absolutely wrong.

Why do you say so?


So I'm curious...I really didn't say much why do you say I'm wrong?

1) You say that you draw the magnet's effect on a particle. But qvxB describes a magnet's effect on a particle. Therefore you are using circular logic which proves nothing.

2) We are not talking about molecules, we are talking about point charges -- in the basic sense, electrons. The spin that I mentioned earlier is a quantum property which has nothing to do with the word "spin" that refers to something rotating on it's axis. There is no rotation about the axis here.