MetaFrizzics

You might want to look at the alternate formulation of Electromagnetic theory for the possibility of exploiting small side-effects:

 

Weber's Electromagnetic theory. It was recognized and approved by Maxwell, but rejected by him in his formulation of Electromagnetics for other reasons (see his explanation). Secondly, the Maxwell equations as we take them now (not the 12 messy ones, but Heaviside's 4 tidy ones) have a probable error in the 'signing' of the formulas, which may mislead experimentors.

To investigate this problem, try reading some work found here:

 

http://www.andrijar.com

 

I found his derivation of the Maxwell equations interesting.

For Weber, look for the treatments by Andre K.T. Assis.

and the maximum output current will still be 15A.

In case the idea isn't clear here, the maximum SAFE output current will be the rated one. If you drop the load resistance too low, more current will flow out of the xformer but this will heat it up and cause a meltdown/short/open circuit. In the process, there is a fire and shock risk, and dangerous gases may be released from the insulating and construction materials burning.

Electrolytic caps have TWO ratings: a constant voltage rating, and a surge rating, about 20% higher than the normal rating. The idea of charging or using an electrolytic cap in a circuit and exposing it to more than its standard rating is bad advice. First of all the ratings are variable between manufacturers and are based upon statistical testing only. If they meant 240 v they'd have said 240 v, not 220 v.

 

(1) Electrolytic caps can never be reliably used in pure A.C. circuits. They work by having the charge that they hold help sustain an insulating film between the plates. In order for electrolytic caps to work reliably, they must be charged to at least 30% of their rated voltage.

 

(2) There are a few specialty caps made that are made out of pairs of electrolytic caps manufactured in one package. They work by placing two caps in series, one in reverse orientation (by tying the +ve leads together internally). These caps however usually have low voltage ratings ( < 120 volts AC) and low capacitance (100 MFD is large). They are made for light-duty audio circuits such as crossover networks inside speaker cabinets. They should not be used in power supplies.

 

(3) Most non-polarized caps have very low capacitance values (e.g., < 100 MFD) but can have higher voltage ratings, such as caps made with insulating mica layers.

 

The typical rule of thumb in building circuits is to OVER-rate the cap's requirements by 20-30% at the minimum. Thus for a full duty-cycle powersupply of 50 volts, it is sensible to use a cap with a 60-80 volt rating (100 v surge). But one should not use one with a rating higher than 150 volts in the same circuit, because the internal dielectric (insulating) layer would be insufficiently formed and there would be internal arcing and shorts.

 

While some (not all) electrolytic caps are 'self-healing', that is, if there is a short, it is momentary, and burns out like a fuze, this leaves the cap with a slightly lower capacitance overall, and too many such incidents will eventually cause the part to fail.

 

Caps should not be exposed to maximum voltage without a charging resistor in series to limit the current while the capacitor is charging up to operating voltage. This resistor can be switched out of circuit by a relay when the cap is charged and ready to go, thus preventing it from hindering the operation of the powersupply when in normal operation.

 

In sum, if you want large capacitance you need either electrolytics or home-made (very large) caps, built according to safety standards regarding fire/shock.

 

Electrolytics have to be charged to 30% of their rating to work reliably.

 

Electrolytics should not be operated higher than to 90% of their rating.

 

Electrolytics should have a charging resistor in series when powered up.

 

Electrolytics should not be used in pure A.C. circuits without special precautions.

 

Manufacturers' ratings should only be used with a safety factor tacked on.

'explosive' effects don't have to be exothermic. Its a question of what you include in the system under consideration. It is trivial to have a large container of say liquid nitrogen 'explode' and freeze all the surfaces it lands on. Just have a 'weak' or 'breakable' container ready to go, and a timer hooked up to an automobile airbag inside. That would make quite the anti-personnel weapon. Conversely, you could store the liquid air or whatever in a cast-iron container easily shattered, and along with the liquified gas have highly pressurized gas in non-liquid form in pouches or balloons. The gas would act as propellant, the liquid would freeze targets, and the container could efficiently produce dangerous shrapnel. People have made all kinds of 'home-made' bombs out of such materials.

 

But freezing is a very inefficient way to kill people, or even maim them. That's why you don't see such weapons on the battlefield everyday. Flying shrapnel or depleted uranium is more deadly. Just picture your typical terrorist, nattering in Arabic, (Translation: )

"Hand over the money, or I will freeze every flea in a 20 foot radius solid, and embrittle your eyebrows, capitalist dogs!"

Nowadays we are taught vectors in school as though they were the original or main thing, almost a trivial 'obvious' solution to the problem of combining forces.

 

Historically, however, physics was branching in two different directions just after Newton:

(1) toward the (Newtonian) deterministic vector-like approach, in which one predicts the evolution of a system by its current state, (velocities & positions of particles), and another more esoteric idea

(2) the 'least action' /work function (Leibnitzian) concept, in which difficult problems could be solved by bypassing detailed individual knowledge of components, but instead concentrate on the evolution of a whole system.

 

Regardless of exact credits (following Euler and Gauss), in England Hamilton and in Germany Grassmann were independantly (? some suspicion there) working on the 2nd branch of physics, which was to evolve into Hamiltonian or Analytical Variational Mechanics, or Calculus of Variations etc. In this process, Hamilton erected the most complete 4-dimensional system (Quaternions) and put it to use solving difficult physical problems. (by the way the DEL operator was first formed by Hamilton).

 

It took Tait and Maxwell however to explore the fantastic territory of Quaternions and create the first real 'field theory' Classical Electromagnetic Theory. Maxwell based his theory on Hamilton's system, although pointed the way to breaking it down into simpler and more practical parts and applications. (Maxwell rejected Grassman's version, and Weber's Electromagnetics, in his own approach although acknowledging their value).

 

But this was still impenetrable until (Gibbs and mainly) Heaviside followed Maxwell's hints and virtually singlehandedly invented both modern 'vectors' and Operational Calculus. So what? Well, Maxwell's original TWELVE messy equations and confusing application of Quaternions was completely cleaned up by Heaviside and modern vectors and Electrical Engineering was born. It was Heaviside who invented and coined virtually all the modern terms like resistivity permeability etc., and who unfortunately goes largely unrecognized for his massive contribution to the age of electricity and electronics. Heaviside systematized Maxwell and created the now common FOUR Maxwell Equations in the form they are now known, and made the science of electrical engineering possible.

 

Just as we now learn Newton in vector form, so we also learn electronics in vector form, thanks to Heaviside's vector calculus.