Inductors, Physics

Assignment Help:

Inductors:

Coils which are used for their opposition to current change in a circuit are known as inductors or chokes.

CONSTRUCTION

Inductors with an air core have small inductance values and are used at high frequencies within radio tuning circuits, or as r.f. chokes to stop radio frequency currents taking certain paths in circuits. Coils for use at high frequency are made of Litz wire which consists of several thin copper wires insulated from each other.

Materials based on iron are used where a large inductance is required. Iron increases the strength of the magnetic field several hundred times. Silicon steel and nickel iron are used at frequencies up to 20kHz.

Iron cores are laminated. The laminations reduce the conversion of electrical energy to heat by making it difficult for currents in the coil to induce currents in the core. These induced currents are called ‘eddy currents' because they flow in circles through the iron core. If the laminations are at right angles to the plane of the coil windings, the core offers a large resistance to the eddy currents.

Iron based cores can be used at high frequencies if the material is in the form of a powder which has been coated with an insulator and pressed together.

Ferrite cores consist of ferric oxide combined with other oxides such as nickel oxide and may also be used at high frequencies.

Iron dust and ferrite cores increase the inductance of a coil considerably. For example, an air cored inductor of 1mH could be increased to 400mH by fitting a ferrite core. These cores also have a high resistance, thereby reducing eddy currents.


Related Discussions:- Inductors

Illustrate what is meant by 4th dimension, Q. Illustrate what is meant by 4...

Q. Illustrate what is meant by 4th dimension? Answer:- When a reference is utilized to four-dimensional co-ordinates it is possible that what is referred to is the three s

Curie weiss law for ferromagnetism, The first question one might ask about ...

The first question one might ask about ferromagnetic material is the source of the large magnetism. The saturation magnetization is so large virtually all the magnetic dipoles in t

Cylindrical volume at a distance x, A long cylindrical volume haves a unifo...

A long cylindrical volume haves a uniformly distributed charge of density ρ and radius R. Determine the electric field at a point P inside the cylindrical volume at a distance x (x

An equilateral triangle is inscribed in a circle of radius, An equilateral ...

An equilateral triangle is inscribed in a circle of radius 2 cm if P lies inside the triangle then the minimum sum of distances of P from the sides of the triangle is?   Ans

Radiation doses in nuclear medicine, Radiation doses in nuclear medicine: ...

Radiation doses in nuclear medicine: Critical organ : the organ receiving the largest dose during a procedure.The dose to a particular organ of the body depends on: 1. Th

Ultrasonics, Industrial applications of ultrasonics

Industrial applications of ultrasonics

Angle calculate by a body be projected, At what angle should a body be pr...

At what angle should a body be projected with a given velocity 24m/s just to pass over the obstacle 14m high at a given distance of 24m. Solution:   14=24xtan(θ)-(g*)(24 2

Physical significance of curl of a vector function, Describe the physical s...

Describe the physical significance of curl of a vector function?

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

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!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd