Table of Contents
Charging of Insulators
Since charge cannot flow through insulators, neither conduction nor induction can be used to charge, insulators, so in order to charge an insulator friction is used. Whenever an insulator is rubbed against a body exchange of electrons takes place between the two. This results in appearance of equal and opposite charges on the insulator and the other body. Thus the insulator is charged.
For example rubbing of plastic with fur, silk with glass causes charging of these things.
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Magnetic Flux
Last modified on:8 years agoReading Time:2MinutesConsider a closed curve enclosing an area A (as shown in the figure). Let there be a uniform magnetic field B in that region. The magnetic flux through the area A is given by Φ = B.A = B A CosΘ where Θ is the angle which the vector B makes with…
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ELECTROMAGNETIC INDUCTION
Last modified on:5 years agoReading Time:2MinutesTopics to be covered: Electromagnetic induction; Faraday’s law, induced emf and current; Lenz’s Law, Eddy currents. Self and mutual inductance. Alternating currents, peak and rms value of alternating current/ voltage; reactance and impedance; LCR series circuit, resonance; Quality factor, power in AC circuits, wattless current. AC generator and transformer. Content: Introduction…
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Introduction (EMI)
Last modified on:5 years agoReading Time:2MinutesIn this lesson we will see how the current and emf are induced in a circuit when the magnetic flux through the circuit changes with time. In 1820, the connection between electricity and magnetism was demonstrated by Faraday and independently by Joseph Henry. They showed that an electric current could be induced in…
