Conductors and Insulators
Solids are mainly classified into two groups, conductors and insulators. In conductors, electric charges are free to move from one place to another, whereas in insulators they are tightly bound to their respective atoms. In an uncharged body, there are equal number of positive and negative charges.
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The examples of conductors of electricity are the metals, human body and the earth and that of insulators are glass, hard rubber and plastics. In metals, the free charges are free electrons known as conduction electrons.
Semiconductors are a third class of materials and their electrical properties are somewhere between those of insulators and conductors. Silicon (Si) and germanium (Ge) are well known examples of semiconductors.
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Charging by Rubbing
Last modified on:5 years agoReading Time:3Minutes Charging by Rubbing The simplest way to charge certain bodies is to rub them against each other. When a glass rod is rubbed with a silk cloth, the glass rod acquires some positive charge and the silk cloth acquires negative charge by the same amount. The explanation of appearance of…
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Conductors and Insulators
Last modified on:5 years agoReading Time:2MinutesConductors and Insulators Solids are mainly classified into two groups, conductors and insulators. In conductors, electric charges are free to move from one place to another, whereas in insulators they are tightly bound to their respective atoms. In an uncharged body, there are equal number of positive and negative charges. The…
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Electric Field Due to a Point Charge
Last modified on:3 years agoReading Time:1MinuteElectric Field Due to a Point Charge The electric field produced by a point charge q can be obtained in general terms from Coulomb’s law.First note that the magnitude of the force exerted by the charge q on a test charge q0 is then divide this value by q0 to obtain…
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Electric Field Due to a Charged Ring
Last modified on:3 years agoReading Time:4MinutesElectric Field Due to a Charged Ring A conducting ring of radius R has a total charge q uniformly distributed over its circumference. We are interested in finding the electric field at point P that lies on the axis of the ring at a distance x from its centre. We divide…
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Electric Field of a Line Charge
Last modified on:3 years agoReading Time:3MinutesElectric Field of a Line Charge Positive charge q is distributed uniformly along a line with length 2a, lying along the y-axis between y=–a and y=+a. We are here interested in finding the electric field at point P on the x-axis. Derivation of electric field due to a line charge: Thus,…
