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

Centrifugal force with a beaded chain, Centrifugal force with a beaded chai...

Centrifugal force with a beaded chain Secure a length of beaded chain like that frequently used for pull cord on electric light switches or for key chains. Fasten the ends toge

Determine the mutual inductance of the coil, The current in a coil changes ...

The current in a coil changes of 5A to 10A in 10 -2 s. Then an emf of 50 mill volts is induced in a coil neat it. Determine the mutual inductance of the coil.

Schrodinger''s wave equation in a three dimensional box., Q. Write down Sch...

Q. Write down Schrodinger's wave equation for a particle in a three dimensional box. Solve it to get eigen functions and show that the eigen values are discrete.  Ans. Fr

Lab, Imagine a small observer is positioned in front of the cork in your pi...

Imagine a small observer is positioned in front of the cork in your picture above. As the cork approaches, the observer measures the wavelength of the waves passing by. How does th

Wavelength, what is the angle of incidence when the refracted and the refle...

what is the angle of incidence when the refracted and the reflected ray are parallel to one another? does this angle depend on the wavelength of light? Ans) The angle of inciden

ACOUSTICS, * Question 1 : Sound A has intensity 10 times the threshold if ...

* Question 1 : Sound A has intensity 10 times the threshold if hearing : sound B has intensity 100 times the threshold of haring . How much louder do we perceive sound B ? * Ques

What are the basic requirements of a laser, What are the basic requirements...

What are the basic requirements of a Laser? Basic requirement of a Laser are as follows: 1. Active Medium: Active basic medium is needed to start the laser action. There

What is the range of the angles of the incident rays, Q . Figure shows acro...

Q . Figure shows across (b)What is the answer if there is no outer covering of the pipe? Answer Reflection, r max = 90 0 -i=90 0 -59 0 =310     Let, i max  b

2d representation of the diamond unit cell, 2D representation of the diamon...

2D representation of the diamond unit cell In a 2D projection of the diamond unit cell, the base plane of the unit cell ABCD is shown by a square and the atoms in the base pla

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