what is a wormhole?

Wormholes are solutions to the Einstein field equations for gravity that act as "tunnels," connecting points in space-time in such a way that the trip between the points through the wormhole could take much less time than the trip through normal space.

The first wormhole-like solutions were found by studying the mathematical solution for black holes. There it was found that the solution lent itself to an extension whose geometric interpretation was that of two copies of the black hole geometry connected by a "throat" (known as an Einstein-Rosen bridge). The throat is a dynamical object attached to the two holes that pinches off extremely quickly into a narrow link between them.

This analysis forces one to consider situations...where there is a net flux of lines of force through what topologists would call a handle of the multiply-connected space and what physicists might perhaps be excused for more vividly terming a ‘wormhole’.

John Wheeler in Annals of Physics

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Monday, May 23, 2011

Tesla Generator

Nikola Tesla, born in 10th July 1856 was a single in the greatest mechanical and electrical engineer from the early 19th century. His perform and invention revolutionized the area of electromagnetism by generating new ideas and generation in alternating present-day electric electrical power process, poly-phase process of electric energy distribution,alternating current motor and so on.

Among all of Tesla's earlier invention, one that really sparks our imagination may be the Tesla Generator. Nikola Tesla generator design can also be generally known as the Tesla coil. The coil was envisioned by Tesla back again in 1891 to build substantial voltage, high present-day and substantial frequency alternating latest electrical power.

The generator core designed was used by Tesla to conduct experiment
inside the spot of electrical lighting, x-ray, phosphorescence, large frequency alternating existing and the most controversial of all, study on transmission of electrical energy with out wires.

Tesla incorporates a theory that energy may be transmitted to your masses devoid of the use of electrical power cables by using his invention. His concept really led to the development with the Wardenclyffe Towerspine in 1901. The tower was located in Prolonged Island, New York and experienced the financial backing of your Wall Road mogul, J.P. Morgan.

Even So, J.P. Morgan made the decision to stop his choice when he find out which the vitality transmitted in the tower could not be metered for fiscal achieve. The Wardenclyffe Tower was hardly ever completed.

A.C Generator


A typical AC generator consists of a stationary stator and a rotor mounted within the stator (see below: Typical AC Generator). The stator contains a specific number of coils, each with a specific number of windings. Similarly, the rotor consists of a http://www.blogger.com/img/blank.gifspecific number of field poles, each with a specific number of windings. In addition to the rotor and stator, a generator has a collector assembly (usually consisting of collector slip rings, brushes, and brush holders). DC flows from the exciter, through the negative brush and slip ring, to the rotor field poles. The return path to the exciter is through the positive brush and slip ring.

Typical AC Generator

Rotor - The rotor contains magnetic fields which are established and fed by the exciter. When the rotor is rotated, AC is induced in the stator. The changing polarity of the rotor produces the alternating characteristics of the current. The generated voltage is proportional to the strength of the magnetic field, the number of coils (and number of windings of each coil), and the speed at which the rotor turns.

Stator - The frame assembly is the main component of the stator. Insulated windings (or coils) are placed in slots near an air gap in the stator core. There is a fixed relationship between the unit’s number of phases and the way the coils are connected. The stator in a four-wire, three-phase unit has three sets of armature coils which are spaced 120 electrical degrees apart. One end of each coil is connected to a common neutral terminal. The other end of each coil is connected to separate terminals. Conductors attached to the four terminals carry the current to the system’s switchgear and on to the load.

Collector slip rings -
Slip rings are usually made of nonferrous metal (brass, bronze or copper); iron or steel is sometimes used. Slip rings usually do not require much servicing. The wearing of grooves or ridges in the slip rings is retarded by designing the machine with limited end-play and by staggering the brushes. Surfaces of the slip rings should be bright and smooth, polishing can be performed with fine sandpaper and honing stone. Electrolytic action can occur at slip ring surfaces producing formation of verdigris. Verdigris is a greenish coating that forms on nonferrous metals. Electrolytic deterioration can be prevented by reversing the polarity of the slip rings once or twice a year. The stator of the three-wire, three-phase unit also has three sets of armature coils spaced 120 electrical degrees apart. The ends of the coils are connected together in a delta configuration. Conductors are attached to the three connecting points.

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