My guess is that as time went on and Betatrons fell out of favor as accelerators, the betatron stuff in the book was dropped or much reduced.
Heh. Here's a great story! At one point many years ago I was offered the Betatron at Case Western Reserve University FREE!!! It was a cute little machine quite a bit smaller than the GE monster in the H&R photo, but still weighed tons due to the iron. All I had to do was haul it away! Happily I came to my senses in time and turned them down!
Whoa! I've been hearing about this theory for quite some time and was interested but could never seem to find any definitive information beyond a description like that above!
Photon-pair annihilation to explain the photo-electric effect! That is totally cool! Do you have a reference to this paper?
Benj (Who has to admit that he isn't sure just what a half-photon might be!)
Yeah you are pretty dumb, but apparently not dumb enough! :-) It's called Lenz's Law and the principle is that when you set up or tear down a magnetic field it always tends to oppose the action you are undertaking. Therefore if you are trying to put a current into an inductor (which sets up the external field) setting up that field will cause the inductor to resist the current you are trying to push through it. Similarly, if the inductor already has a current flowing, the collapsing field will try to keep the current going, namely resist your actions of trying to STOP the current. so yeah, you are correct. The basic idea is that in shoving current through an inductor you are in essence shoving energy into the magnetic field about it where it is stored. Later when you try to stop the current, all that stored energy comes back out of the field and does so in a direction that tends to keep the current flowing in spite of your efforts to stop it.
Depending on your point of view:-)Actually your question is a very smart one.Maybe it's God's will (or a higher being's) that we can't get energy for free (there's no such thing as a free lunch).Because then we could place a piece of wire in Earth's magnetic field and get electricity,plenty and free, wouldn't we? But maybe He doesn't want to spoil us;-)So we have to rotate generators with prime movers, which on their turn need some fuel....Fuel costs money, and their supply is limited....Google for the perpetuum mobile, for an encore....
-- Tzortzakakis Dimitrios major in electrical engineering mechanized infantry reservist dimtzort AT otenet DOT gr
In my edition, it became section 35-6 (3 pages worth)
Your quote about conservative-nonconservative is the last sentence of the previous section (35-5 Time-Varying Magnetic fields)
What I gather from nonconservative bit is simply that E fields associated with changing magnetic fields transmit energy to the test charge, causing it to change its state of motion. changing magnetic field
It is a fact that not much can be found on this wonderful device.
Humphries book "Principles of Charged Particle Acceleration" that I gave a reference to earlier does pretty much cover all aspects of betatron operation.
No kidding ! What a loss! Do you remeber how many tons ? Would you know if they still have it ?
Yes. Well, there is a very special problem with de Broglie's work. Although he was instrumental with his 1924 thesis in giving Schr=F6dinger his lead to develop his famous equation, the community always treated him as some sort of weird cookie, because he was a causalist.
Meaning that he was convinced that elementary particles were at all times localized, even as they are moving, which includes photons and also electrons (and positrons), and this despite his understanding of QM as a proper mathematical description (Einstein agreed with him also).
This idea was discussed at the time, but to my knowledge no formal paper ever came to be published on this issue.
To my knowledge, no causalist work was accepted for formal publication since the early 1960's, whoever promising.
He even had to set up a foundation to make certain that his work would not be lost.
It certainly is.
As I said, no formal paper was published, to my knowledge. He was however a very prolific writer and published a number of books, some of which are still being constantly re-edited in French. I don't believe there is anything available in English on this.
The one ref I can give you still in print is this well known book of his
"La physique nouvelle et les quanta", Flammarion, France 1937, Second Edition 1993, with new 1973 preface by L. de Broglie Page 277.
But if you are not convinced yourself of the permanent localization of elementary particles, I am afraid, even if you can read French, that what he says will remain just about meaningless to you.
: : The magnetic field of a permanent magnet is caused by currents inside : the body of the magnet.
And you know this how?
The electrostatic field of a capacitor is caused by fluxes in the body of the capacitor, you can't get a static electric field unless there's a flux somewhere. You don't buy my theory, huh? I don't buy yours, then.
The fields produced by the charge and current are the D and H fields. The fields *experienced* by the charge and current are the E and B field.
In a vacuum or near-vacuum, the two sets are linearly related (D = epsilon_0 E, B = mu_0 H); but not necessarily so -- even in a vacuum when very close to a charge, to the point of practically being on top of it. Confusion may result from failing to distinguish sufficiently these two sets of fields.
If there were such things as magnetic charges and currents, it would be other way around: the E and B fields would be those produced by magnetic charges and currently, while the D and H fields would be those experienced by the magnetic sources.
*That* is the symmetry you're alluding to! It's not there, because magnetic sources are not known to exist.
In this light, this will also help make more sense of the units in electromagnetism. The units of electric and magnetic charge are, respectively, Coulomb and Weber. The corresponding units of their currents would be Coulomb/second and Weber/second, which are respectively termed the Amp and Volt.
Electric potential has the same units as magnetic current (and vice versa, magnetic potential is equivalent in units to electric current). Older technology, in fact, used such things as magnetic circuits. Though there are no magnetic monopoles, it's still meaningful to talk about effective magnetic currents and the like.
This, in turn, will help further make sense of the three fundamental linear circuit elements and their corresponding units. A resistor and conductor are measured, respectively, in Ohms and Mhos (and a Mho which is Ohm spelled backwards is now called a Siemens). An Ohm is a Volt/Amp or Weber/Coulomb; a Mho a Amp/Volt or Coulomb/Weber.
A capacitor stores electrical energy and has a law of the form I = C dV/dt (or Q = CV). The units of the capacitance (C) are Farad = Coulomb/Volt or, equivalently, Amp-second/Volt or Coulomb-second/ Weber. An inductor stores magnetic energy and has a law of the form V = L dI/dt. If there had been an actual magnetic analogue of a capacitor, it would have an analogous behavior to an inductor and satisfy the same relation, only now with V interpreted as magnetic current, and I as magnetic potential. So, the units of inductance (L) are Henri = Weber/Amp = Volt-second/Amp = Weber-second/Coulomb.
In the presence of magnetic sources (with charge density s, current density K) and electric sources (charge density r, current density J), the field laws would read:
div D = rho; curl H - dD/dt = J div B = sigma; curl E + dB/dt = -K
the force density would be
F = r E + J x B + s H - K x D
and the power density
P = J.E + K.H
where (x) denotes vector cross product, and (.) scalar product, and d/ dt the partial derivative with respect to time.
In terms of fluxes and circulations, let V denote a volume, and dV the surface bounding the volume associated with an outward orientation. Let S denote a surface, with a given orientation attached to it, and dS the boundary of the surface equipped with an counter-clockwise orientation around the surface, when the surface is oriented with its "top" side up.
Denote by D(S), B(S), I(S), K(S) respectively, the fluxes of D, B, J and K with respect to a given surface S. Let Q(V), P(V) denote the total charges (corresponding, respectively, to electric charge density r and magnetic charge density s) contained in a volume V. Let E(C) and H(C), respectively, denote the circulations of E and H along an oriented curved C.
Then the 4 equations above read:
D(dV) = Q(V) -- Gauss' Law for electric charges B(dV) = P(V) -- Gauss' Law for magnetic charges H(dS) = d/dt D(S) + I(S) -- Ampere's Law for electric currents
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