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Chapter 30

Electromagnetic Induction

Indukcja
Indukcja
An emf is induced when the magnetic field in a coil is changed by pushing a bar magnet into or out of the coil. emfs of opposite signs are produced by ...
Prawo Faradaya
Prawo Faradaya
Faraday's law state that the induced emf is the negative change in the magnetic flux per unit of time. Any change in the magnetic field or change in ...
Prawo Lenza
Prawo Lenza
The direction in which the induced emf drives the current around a wire loop can be found through the negative sign. However, it is usually easier to ...
Ruchomy Emf
Ruchomy Emf
Magnetic flux depends on three factors: the strength of the magnetic field, the area through which the field lines pass, and the field's orientation ...
Faraday Disk Dynamo
Faraday Disk Dynamo
A Faraday disk dynamo is a DC generator, producing an emf that is constant in time. It consists of a conducting disk that rotates with a constant angular ...
Indukowane pola elektryczne
Indukowane pola elektryczne
The fact that emfs are induced in circuits implies that work is being done on the conduction electrons in the wires. What can possibly be the source of ...
Indukowane pola elektryczne: zastosowania
Indukowane pola elektryczne: zastosowania
An important distinction exists between the electric field induced by a changing magnetic field and the electrostatic field produced by a fixed charge ...
Prądy wirowe
Prądy wirowe
Since eddy currents occur only in conductors, magnets can separate metals from other materials. For example, in a recycling center, trash is dumped in ...
Prąd przemieszczenia
Prąd przemieszczenia
Ampère's law, in its usual form, does not work in places where the current changes with time and is not steady. Thus, Maxwell suggested including ...
Znaczenie prądu przemieszczenia
Znaczenie prądu przemieszczenia
A displacement current is analogous to a real current in Ampère's law, participating in Ampère's law the same way as the usual ...
Pola elektromagnetyczne
Pola elektromagnetyczne
Electric fields generated by static charges, often referred to as electrostatic fields, are characteristically different from electric fields created by ...
Równanie elektromagnetyzmu Maxwella
Równanie elektromagnetyzmu Maxwella
James Clerk Maxwell (1831–1879) was one of the major contributors to physics in the nineteenth century. Although he died young, he made major ...
Symetria w równaniach Maxwella
Symetria w równaniach Maxwella
Once the fields have been calculated using Maxwell's four equations, the Lorentz force equation gives the force that the fields exert on a charged ...
Prawo Ampera-Maxwella: rozwiązywanie problemów
Prawo Ampera-Maxwella: rozwiązywanie problemów
A parallel-plate capacitor with capacitance C, whose plates have area A and separation distance d, is connected to a resistor R and a battery of voltage ...
Postać różniczkowa równań Maxwella
Postać różniczkowa równań Maxwella
James Clerk Maxwell (1831–1879) was one of the significant contributors to physics in the nineteenth century. He is probably best known for having ...
Generator elektryczny: Alternator
Generator elektryczny: Alternator
Electric generators induce an emf by rotating a coil in a magnetic field. A simple alternator is an AC generator that creates electrical energy that ...
Generator prądu stałego
Generator prądu stałego
An alternator converts mechanical energy into electrical energy that varies sinusoidally, resulting in AC current. Meanwhile, a DC generator converts ...
Plecy EMF
Plecy EMF
Generators convert mechanical energy into electrical energy, whereas motors convert electrical energy into mechanical energy. A motor works by sending a ...
Tłumienie magnetyczne
Tłumienie magnetyczne
Eddy currents can produce significant drag on motion, called magnetic damping. For instance, when a metallic pendulum bob swings between the poles of a ...
Nadprzewodnik
Nadprzewodnik
A substance that reaches superconductivity, a state in which magnetic fields cannot penetrate, and there is no electrical resistance, is referred to as a ...
Rodzaje nadprzewodników
Rodzaje nadprzewodników
A superconductor is a substance that offers zero resistance to the electric current when it drops below a critical temperature. Zero resistance is not the ...
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