A Wisdom Archive on Explosively pumped flux compression generator

The most widespread and developed design for an EPFCG is the coaxial design. This consists of a cylindrical core of high explosive surrounded by a conductive armature tube, an air gap, then a conductive winding. In operation, the start current is supplied to the conductive winding from one end of the device, and the explosive is detonated from the same end. As the explosion propagates along the explosive core it forces the armature tube out across the air gap and into contact with the winding, forcing the magnetic flux in the air gap ...

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The worst of the pulse lasts for only a second, but any unprotected electrical equipment - and anything connected to electrical cables, which act as giant lightning rods or antennas, will be affected by the pulse. Older, tube or valve-based equipment is much less vulnerable to EMP. There are a number of websites that explore methods for protecting equipment in the home or business from the effects of an EMP attack. It is important to note that many nuclear detonations have taken place using bombs dropped by aircraft. The aircraft that ...

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Typical modern scenarios seen in news account speculate about the use of nuclear weapons by rogue states or terrorists in an attack on the United States. These typically involve weapons the similar to those used over Hiroshima and Nagasaki. Aerial detonation would require the use of aircraft, or surface launched missiles of limited range (typically a range 100 to 300 miles). Detonations would typically occurred within the earth's atmosphere, and likely ...

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An example of the second definition of flux is the magnitude of a river's current, that is, the amount of water that flows through a cross-section of the river each second. The amount of sunlight that lands on a patch of ground each second is also a kind of flux. To better understand the concept of flux in Electromagnetism, imagine a butterfly net. The amount of air moving through the net at any given instant in time is the flux. If the wind speed is high, then the flux through the net is large. If the net is made bigger, then the flux would ...

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Capacitor - Circuits with DC sources. Electrons cannot directly pass across the dielectric from one plate of the capacitor to the other. When there is a current through a capacitor, electrons accumulate on one plate and electrons are removed from the other plate. This process is commonly called 'charging' the capacitor even though the capacitor is at all times electrically neutral. In fact, the current through the capacitor results in the separation rather than the accumulation of electric charge. This separation ...

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There are many fluxes used in the study of transport phenomena. Each type of flux has its own distinct unit of measurement along with distinct physical constants. Five of the most common forms of flux from the transport literature are defined as: Momentum flux, the rate of change of momentum moving across a unit area (N/m2). (Newtonian fluid, viscous flow) Heat flux, the rate of heat flow across a unit area (J/(m2 s)). (Fourier's Law) Chemical flux, the rate of movement of moles across a unit area (moles/(m2 s) ...

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Flux, or diffusion, for gaseous molecules can be related to the function: where N is the total number of gaseous particles, k is Boltzmann's constant, T is the relative temperature in kelvins, and σab is the mean free path between the molecules a and b. Chemical molar flux of a component A in an isothermal, isobaric system is also defined in ...

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Capacitors may retain a charge long after power is removed from a circuit; this charge can cause shocks (up to and including electrocution) or damage to connected equipment. Since capacitors have such low equivalent series resistances (ESRs), they have the capacity to deliver large currents into short circuits; this can be dangerous. Care must be taken to ensure that any large or high-voltage capacitor is properly discharged before servicing the containing equipment. For safety purposes, all large capacitors should be discharged before handl ...

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In circa 600 BC, Thales of Miletus recorded that the Ancient Greeks could generate sparks by rubbing balls of amber on spindles. This is the triboelectric effect, the mechanical separation of charge in a dielectric. This effect is the basis of the capacitor. In October 1745, Ewald Georg von Kleist of Pomerania invented the first recorded capacitor: a glass jar coated inside and out with metal. The inner coating was connected to a rod that passed through the lid and ended in a metal sphere. By layering the insulator between two metal plates, von Kleist d ...

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Capacitor - Overview. A capacitor consists of two electrodes or plates, each of which stores an opposite charge. These two plates are conductive and are separated by an insulator or dielectric. The charge is stored at the surface of the plates, at the boundary with the dielectric. Because each plate stores an equal but opposite charge, the total charge in the capacitor is always zero.

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In practice, this ideal model of the capacitor often has to be modified to reflect real world capacitor construction and operation. The most obvious example is electrolytic capacitors, where the capacitor is polarized such that when the voltage is connected in reversed fashion, the capacitor acts as a resistor. Similar problems of dielectric leakage are a constant complication of all capacitor design however, and have led to constant improvements in capacitor design, as the material used for dielectrics has changed from oiled paper to mylar ...

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This term covers the mains power distribution system together with any other primary or secondary sources of energy such as: Batteries Chemical fuel cells and other forms of energy storage systems Solar power Conversion of one form of electrical power to another desired form and voltage. This typically involves converting 120 or 240 volt AC supplied by a utility company (see electricity generation) to a well-regulated lower voltage DC for electronic devices. For examples, see switched-mode power supply ...

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Capacitors have very many uses in electronic and electrical systems. Capacitor - Energy storage. A capacitor can store electric energy when disconnected from its charging circuit, so it can be used like a temporary battery. The recent commercial availability of very large value capacitors, one farad in size and larger, has enabled such components to allow batteries to be changed in electronic devices without the memory being lost, for instance, or for energy storage for delivery during extreme peak demands, as often found in the enormously powerful car audio systems now seen.

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