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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Electric Field of a Line Charge
Last modified on:3 years agoReading Time:3MinutesElectric Field of a Line Charge Positive charge q is distributed uniformly along a line with length 2a, lying along the y-axis between y=–a and y=+a. We are here interested in finding the electric field at point P on the x-axis. Derivation of electric field due to a line charge: Thus,…
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Electric Field Lines
Last modified on:3 years agoReading Time:5MinutesElectric Field Lines Electric charges create an electric field in the space surrounding them. It is useful to have a kind of “map” that gives the direction and indicates the strength of the field at various places. Field lines, a concept introduced by Michael Faraday, provide us with an easy way…
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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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Extra Questions for Class 12 Biology Chapter 8 Human Health and Diseases
Last modified on:4 years agoReading Time:8MinutesExtra Questions for Class 12 Biology Chapter 8 Human Health and Diseases Q.1. Why is Gambusia introduced into drains and ponds?Ans. To feed on mosquito larvae so as to eliminate the vectors responsible for causing malaria. Q.2. Name any two physiological barriers that provide innate immunity? Ans. Acid in stomach/saliva in…
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Extra Questions for Class 12 Biology Chapter 7 Evolution
Last modified on:4 years agoReading Time:15MinutesExtra Questions for Class 12 Biology Chapter 7 Evolution Q.1. What is fossil?Ans. Fossils are the remains or impressions of ancient organisms preserved in sedimentary rocks or other media. Q.2. Life originated from earth’s inorganic atmosphere in past but not today. Suggest two reason.Ans. (i) Presence of free oxygen in present…
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Extra Questions for Class 12 Biology Chapter 5 Principles of Inheritance and Variation
Last modified on:4 years agoReading Time:17MinutesExtra Questions for Class 12 Biology Chapter 5 Principles of Inheritance and Variation Q.1. A garden pea plant produced axial white flowers. Another of the same species produced terminal violet flowers. Identify the dominant traits.Ans. Axial, violet flower. Q.2. When a tall pea plant was self-pollinated, one-fourth of the progeny were…
