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!
A VDR is a special type of resistor that changes its resistance with rise in voltage. It has a very high resistance at low voltage (below the trigger voltage) and very low resistance at high voltage (above the trigger voltage). It is also called varistor or voltage sensitive resistor. There are two types of varistor.
SILICON CARBIDE VARISTOR:-
MANUFACTURING: These are made up of silicon carbide. It is milled and mixed with a suitable ceramic binder. Then it pressed and extruded to desired shape of disc, rod or washer. Then it is sintered under controlled temperature to produce hard material. Wire leads are then connected.
METAL-OXIDE VARISTOR (MOV):
MANUFACTURING:
Zinc oxide and bismuth oxides are mixed with other powdered metal additives, pressed into discs and sintered at 12000C. It has an encapsulated polycrystalline ceramic body; with metal contacts and wire leads.
APPLICATIONS: A varistor acts as a switch. It is usually used for short circuit protection in power strips or lightning bolts "arrestors" on street power poles. It is also used as a "snobbier" in inductive circuits.
Explain electric flux. Write its S.I. units. A spherical rubber balloon carries a charge that is uniformly distributed over its surface. As the balloon is blown up and enhances in
Question: In estimate the integral one evaluates in applying Ampere's Law one is Answer: The integral in Ampere's Law is a path integral and the path is an imaginary c
A 5.0-cm-tall object is placed 16 cm from a convex lens with a focal length of 8.4 cm. What are the image height and orientation?
A coil of inductance 318.3mH and negligible resistance is linked in series with a 200 resistor to a 240V, 50Hz supply. Calculate (a) The inductive reactance of the coil,
Show the mathematical relation connecting n,u,v and R for refraction at a spherical surface concave towards a point object in a denser medium producing a virtual image.
Characteristics of resistances connected in parallel
Explain power of a lens. What is the principle of an optical fibre? What is a thin prism? Describe angular dispersion between two colours for a prism.
An atom which has lost one electron would be: (1) Negatively charged () Positively charged (3) Electrically neutral (4) Carry double positive charge Ans: Elec
An astronaut on a small planet wishes to measure the local value of g by timing pulses traveling down a wire which hasa large object suspended from it. Assume a wire of mass3.50
Explain Radioactivity and its Problems and Applications ? All radiation, electromagnetic as well as the kind from nuclear decay, takes its toll on living organisms. If the radiati
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