Table of Contents
Charging by Contact
When a negatively charged ebonite rod is rubbed on a metal object, such as a sphere, some of the excess electrons from the rod are transferred to the sphere. Once the electrons are on the metal sphere, where they can move readily, they repel one another and spread out over the sphere’s surface. The insulated stand prevents them from flowing to the earth. When the rod is removed, the sphere is left with a negative charge distributed over its surface. In a similar manner, the sphere will be left with a positive charge after being rubbed with a positively charged rod. In this case, electrons from the sphere would be transferred to the rod. The process of giving one object a net electric charge by placing it in contact with another object that is already charged is known as charging by contact.

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Conductors and Insulators
Last modified on:4 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…
