Already have an account? Get multiple benefits of using own account!
Login in your account..!
Remember me
Don't have an account? Create your account in less than a minutes,
Forgot password? how can I recover my password now!
Enter right registered email to receive password!
What is dielectric breakdown? Explain briefly the various factors contributing to breakdowns in dielectrics.
Ans.: Electric Breakdown: When the electric field applied across any substance exceeds threshold breakdown field for that substance, the insulator suddenly turns into a resistor, Here a large usually abrupt rise in electric current is produced small increase in electric voltage. Breakdown can be intentional and controlled of accidental. Lightning is the most familiar example of breakdown.
Electrical breakdown in Gas: In a gas, the potential gradient may become high enough to accelerate the naturally present may become high enough to accelerate the naturally present ions to such velocities that cause further ionization upon collision with other atoms. The process is corona discharge. If the region of ionization does not extend between oppositely charged electrodes, if the ionization region the gap between electrodes breaking down the insulation provided by the gas the process is ionization discharge. When controlled by the ballast of a fluorescent lamp the process converts electric power to light.
Electrical Breakdown in Solid: In a solid, when the electric field gradient exceeds valence bonds between atoms are broken and current flows. Such a disruptive current heats the solid abruptly. During electrical breakdown, any free charge carrier being accelerated by the strong electric field will have enough velocity to knock electrons from any atom it strikes. Rapidly the insulator becomes filled with mobile carriers due to creation of more and more charge carriers and its resistance drops. In are the outbreak of conductivity is called corona discharge or a spark.
Application: Electrical breakdown can be useful in every day applications such as spark plugs for gasoline engines, electrical welding of metals of for metal melting in an electric arc fumace.
A highly polished metal surface is coated with a colloidal aqueous dispersion of P.T.F.E. it is force dried and sintered, until a continuous film is formed. These capacitors can wi
Q. What is the dissimilarity between isolation transformers and step up or step down transformer? Answer:- In fact an isolation transformer may be physically the same as a
compare the electrostatic force between two protons to the gravitational force acting on them?
Does a piece of glass reflect more light than a piece of paper?
Consider the water heat distribution system shown below where: The fractions refer to the fraction of the stream ?owing, e.g. 20% of the stream leaving the 100,000 Btu/ hr heate
Moment of Thin Spherical Shell About Axis This problem can be set up in spherical coordinates so that conversions from Cartesian coordinates are not required. The mass element
Kerr effect (J. Kerr; 1875): The ability of certain substances to refract light waves differently whose vibrations are in distinct directions while the substance is placed wit
Working of a galbanometer?
Q. How is radiation release from the body? Answer:- The body radiates energy by thermal conduction through the skin to the clothes, air, and so on around the body. A littl
CANT understand anything!!
Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!
whatsapp: +91-977-207-8620
Phone: +91-977-207-8620
Email: [email protected]
All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd