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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Numerical Problems Based on Biot-Savart Law for Class 12 Physics
Last modified on:4 weeks agoReading Time:9Minutes Numerical Problems on Biot-Savart Law Class 12 Physics · Moving Charges and Magnetism SQ Biot-Savart Law Practice Set Apply $d\vec{B} = \frac{\mu_0}{4\pi} \frac{I d\vec{l} \times \hat{r}}{r^2}$ Ch 4 · Moving Charges and Magnetism 1 A wire placed along east-west direction carries a current of 10 A from west to east…
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Numerical Problems Based on Kirchhoff’s Laws for Class 12 Physics
Last modified on:4 weeks agoReading Time:10Minutes Numerical Problems on Kirchhoff’s Laws Class 12 Physics · Current Electricity SQ Kirchhoff’s Circuit Laws Practice Set Apply KCL $\sum I = 0$ and KVL $\sum \Delta V = 0$ Ch 3 · Current Electricity 1 Apply Kirchhoff’s rules to the loops PRSP and PRQP to write the expressions for…
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Numerical Problems Based on Heating Effects of Electric Current for Class 12 Physics
Last modified on:4 weeks agoReading Time:24Minutes Numerical Problems on Heating Effects of Electric Current Class 12 Physics · Current Electricity SQ Electric Power and Heating Effects Practice Set Apply $H = I^2Rt$, $P = VI$, and $P = \frac{V^2}{R}$ Ch 3 · Current Electricity 1 Calculate the current flowing through a heater rated at 2 kW…
