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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Physics MCQs for Class 12 with Answers Chapter 10 Wave Optics
Last modified on:5 years agoReading Time:31MinutesQ.1. The locus of all particles in a medium, vibrating in the same phase is called(a) wavelet(b) fringe(c) wave front(d) None of these Answer Answer: (c) Q.2. Which of the following is correct for light diverging from a point source?(a) The intensity decreases in proportion for the distance squared.(b) The wavefront…
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Physics MCQs for Class 12 with Answers Chapter 11 Dual Nature of Matter and Radiation
Last modified on:5 years agoReading Time:24MinutesQ.1. Cathode ray consists of(a) photons (b) electrons(c) protons (d) α-particles Answer Answer: (b) Cathode ray consists of electrons Q.2. A discharge takes place between the two electrodes on applying the electric field to the gas in the discharge tube. The cause of this fluorescence was attributed to(a) the radiations which…
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Physics MCQs for Class 12 with Answers Chapter 12 Atoms
Last modified on:5 years agoReading Time:27MinutesQ.1. Balmer series lies in which spectrum?(a) visible(b) ultraviolet(c) infrared(d) partially visible, partially infrared Answer Answer: (b) Q.2. In Bohr model of hydrogen atom, let P.E. represents potential energy and T.E. represents the total energy. In going to a higher level.(a) P. E. decreases, T.E. increases(b) P. E. increases, T.E. decreases(c)…
