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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Extra Questions for Class 12 Biology Chapter 9 Strategies for Enhancement in Food Production
Last modified on:4 years agoReading Time:6MinutesExtra Questions for Class 12 Biology Chapter 9 Strategies for Enhancement in Food Production Q.1. A herd of cattle is showing reduced fertility and productivity. Provide one reason and one suggestion to overcome this problem. Ans. Inbreeding depression or continuous inbreeding may be the reason of reduced fertility and productivity. To…
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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…
