Basic electromagnetic principles, Electrical Engineering

Assignment Help:


It has been known for a thousand years or more (originating in China) that certain (magnetic) materials would always orientate    themselves in a  particular direction if suspended to rotate freely. The very earliest experiments in magnetism were done with these materials (permanent magnets)  and  these  clearly  showed  that two pieces of these materials were able to exert some force at a distance. This force is analogous to gravitational force. We know from our own experience that it exists. Physicists theorise on the causes whilst engineers are more concerned with being able to measure the practical effect and put it to use by devising a suitable method of analysis.

Very early experiments by Oersted and Ampere showed that a current carrying conductor also had an effect on magnetic material    in    its  vicinity.   Magnetic compasses   placed    near    to    a    current carrying conductor were deflected. He also found that the direction of deflection depended on the position relative to the wire. Those above the wire were deflected in the opposite direction to  those placed below. Ampere quantified the strength of this force in terms of the current and the distance involved.
 

In    order  to  be    able   to  relate   these observations to analysis, the concept of a magnetic field was introduced.The presence of a magnetic field may be visualised  by  drawing   imaginary continuous  lines  of    'magnetic  flux',  the density of which is a measure of the strength of the field  in a given material. Arrows are added to the flux lines to indicate the direction of the magnetic field, from which the  direction  of the  force  it produces on, for example, compass needles and current carrying conductors can be deduced. Convention has it that the magnetic field strength is denoted by the symbol H  (ampere.turns),  whilst magnetic  flux density  is  given  the symbol B (Webers/m2).


Related Discussions:- Basic electromagnetic principles

Explain the modes of connection for polyphase transformers, Discuss the mod...

Discuss the modes of connection for polyphase transformers Discuss with aid of electrical grouping and wiring connection diagrams the different types of connections for polypha

Society in engineering, cite a specific example in which the engineer must ...

cite a specific example in which the engineer must provide maximum efficiency for a given cost.

Clipper, how to write kvl equation in series clipper circuit without any ba...

how to write kvl equation in series clipper circuit without any battery

Transistor, what is bias compensation

what is bias compensation

Static v- i characteristics - power semiconductor devices , Static V- I Cha...

Static V- I Characteristics A thyristor  works in  three basic  modes a.Reverse  blocking mode b.Forwards  blocking  mode and c.Forward  conducting  mode In revers

What is the purpose of carry flag and zero flag, What is the purpose of car...

What is the purpose of carry (c) flag and zero (z) flag? Carry flag conatins the carry after addition or borrow after subtraction. This carry flag also shows error conditions,

Cro, Ask question #Minimum 100 words accepteddelay line in cro#

Ask question #Minimum 100 words accepteddelay line in cro#

Effect of supply voltage - stepper motor , Effect of Supply  Voltage ...

Effect of Supply  Voltage a.As the applied  as voltage  is increased hysteresis loss increases. b.Eddy current losses are given by W e α f 2 t 2 B 2 m Where B m =

Registers - introduction to microprocessors , Registers A resister is ...

Registers A resister is  a group  of flip  flops  or binary  cells which holds  the binary information. Since  a binary cell  stores  one  bit of  information  an n bit  regis

Show the dot convention, Q. For the coupled coils shown in Figure, a dot ha...

Q. For the coupled coils shown in Figure, a dot has been arbitrarily assigned to a terminal as indicated. Following the dot convention presented in the text, place the other dot in

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