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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COULOMB’S LAW
Last modified on:3 years agoReading Time:18MinutesCOULOMB’S LAW: Two point electric charges q1 and q2 at rest, separated by a distance r exert a force on each other whose magnitude is given by If between the two charges there is free space then Where ε0 is the absolute electric permittivity of the free space and ε0 =…
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If we comb our hair on a dry day and bring the comb near small pieces of paper, the comb attracts the pieces, why?
Last modified on:4 years agoReading Time:2Minutes If we comb our hair on a dry day and bring the comb near small pieces of paper, the comb attracts the pieces, why? Answer: This is an example of frictional electricity and induction. When we comb our hair, it gets positively charged by rubbing. When the comb is brought…
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Can two similarly charged bodies attract each other?
Last modified on:4 years agoReading Time:1Minute Yes, when the charge on one body Q is much greater than that on the other q and they are close enough to each other so that force of attraction between Q and induced charge on the other exceeds the force of repulsion between Q and q. However, two similar…
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Assertion Reason Questions for Class 7 Science Chapter 15 Light
Last modified on:3 years agoReading Time:13Minutes[Download] Assertion Reason Questions for Class 7 Science Chapter 15 Light Here we are providing assertion reason questions for Chapter 15 Light. Directions: The question below consists of an assertion and a Reason. Use the following key to choose the appropriate answer.(a) Both A and R are true and R is…
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Assertion Reason Questions for Class 7 Science Chapter 14 Electric Current and Its Effect
Last modified on:3 years agoReading Time:13Minutes[Download] Assertion Reason Questions for Class 7 Science Chapter 14 Electric Current and Its Effect Here we are providing assertion reason questions for Chapter 14 Electric Current and Its Effect. Directions: The question below consists of an assertion and a Reason. Use the following key to choose the appropriate answer.(a) Both…
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Assertion Reason Questions for Class 7 Science Chapter 13 Motion and Time
Last modified on:3 years agoReading Time:13Minutes[Download] Assertion Reason Questions for Class 7 Science Chapter 13 Motion and Time Here we are providing assertion reason questions for Chapter 13 Motion and Time. Directions: The question below consists of an assertion and a Reason. Use the following key to choose the appropriate answer.(a) Both A and R are…
