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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Case Study Questions for Class 9 Maths Chapter 13 Surface Area and Volume
Last modified on:4 years agoReading Time:3MinutesCase Study Questions Question 1: Nakul was doing an experiment to find the radius r of a ball. For this he took a cylindrical container with radius R = 7 cm and height 10 cm. He filled the container almost half by water as shown in the figure-1. Now he dropped…
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Case Study Questions for Class 9 Maths Chapter 10 Circles
Last modified on:2 years agoReading Time:3MinutesCase Study Questions for Class 9 Maths Chapter 10 Circles Case Study Questions Question 1: Ankit visited in a mall with his father. He sees that three shops are situated at P, Q, R as shown in the figure from where they have to purchase things according to their need. Distance…
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Case Study Questions for Class 9 Maths Chapter 9 Quadrilaterals
Last modified on:4 years agoReading Time:3MinutesCase Study Questions Question 1: After summervacation, Manit’s class teacher organised a small MCQ quiz, based on the properties of quadrilaterals. During quiz, she asks different questions to students. Some of the questions are listed below. (i) Which of the following is/are the condition(s) for ABCD to be a quadrilateral?(a) The…
