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

What are the different types of distributing frames, Q. What are the differ...

Q. What are the different types of distributing frames used in exchanges? Ans: Different distribution  frames  used  in  exchange  are  displayed in  figure.  Each subscribe

Determine the laplace transform of the given functions, Q. Determine the La...

Q. Determine the Laplace transform for each of the following functions from the basic de?nition of Equation. (a) f 1 (t) = u(t) (b) f 2 (t) = e-at (c) f 3 (t) = df (t) dt,

Calculate minimum number of poles for the induction machine, A wound-rotor ...

A wound-rotor induction machine, driven by a dc motor whose speed can be controlled, is operated as a frequency changer. The three-phase stator winding of the induction machine is

Simulate the circuit using digital simulation techniques, You are the new c...

You are the new chief PCB designer for a small company who are about to become heavily involved in the design and realisation of digital timing products. Your management wants to p

Explain digital signal formatting, Q. Explain Digital Signal Formatting? ...

Q. Explain Digital Signal Formatting? After quantization and coding the samples of the message, a suitable waveform has to be chosen to represent the bits. This waveformcan the

Discuss power failure detection circuit interrupt nmi, Draw and discuss pow...

Draw and discuss power failure detection circuit interrupt NMI. The non-maskable interrupt (NMI) is an edge-triggered input which requests can interrupt upon the positive-edge.

Explain working of common drain amplifie, Q. Explain working of Common drai...

Q. Explain working of Common drain amplifie? When an ac signal drives the gate of JFET, it produces an ac drain current. It flows through Rs and produces an ac output voltage t

What is the voltage gain of common gate amplifier, Q. What is the voltage g...

Q. What is the voltage gain of common gate amplifier? The controlled source gmVgs is connected from drain to source with rd in parallel.The resistor is connected Rs is connecte

Determine the percentage ripple voltage, Problem (a) Figure gives the ...

Problem (a) Figure gives the basic circuit of the diode limiter. Assuming that the diodes are ideal sketch and annotate the waveforms of the input voltage vi(t) and the load

Statics, a mass of 20 kg is lifted u p to the roof of a cliff 100 m high.de...

a mass of 20 kg is lifted u p to the roof of a cliff 100 m high.determie Ep of the mass while it is at the top

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