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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Reynolds Number
Last modified on:3 years agoReading Time:10MinutesWhat is Reynolds Number? The Reynolds number (Re) is a dimensionless parameter used in fluid mechanics to characterize the flow of a fluid (liquid or gas) around an object or through a conduit. It relates the inertial forces to the viscous forces in the fluid and helps determine the type of…
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Human Ear
Last modified on:4 years agoReading Time:3MinutesHuman Ear The human ear, like that of other mammals, contains sense organs that serve two quite different functions: that of hearing and that of head and eye movements. Anatomically, the ear has three distinguishable parts: the outer, middle, and inner ear. How Human Ear Works? Different sounds produced in our surroundings are collected by…
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Numericals for Class 9 Science Chapter 12 Sound
Last modified on:3 years agoReading Time:14MinutesNumericals for Class 9 Science Chapter 12 Sound Q.1. A boy hears an echo of his own voice from a distant hill after 1 s. the speed of sound is 340m/s. What is the distance of the hill from the boy? Q.2. An engine is approaching a hill at constant speed.…
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Problems Based on Class 9 Science Chapter 10 Gravitation
Last modified on:4 years agoReading Time:6Minutes Q.1. An object weighs 10N when measured on the surface of the earth. What would be its weight when measured on the surface of the Moon? Q.2. Mass of an object is 10kg. What is its weight on Earth? Q.3. What is the mass of an object whose weight is…
