Understanding electromagnetic fields

Electromagnetic Field

Understanding electromagnetic fields Before we know around us , especially in our household containing electromagnetic fields . So what exactly is the electromagnetic field ? whether the electromagnetic field ?

Electromagnetic field , is sometimes referred to as the EM field , produced when charged particles , such as electrons , are accelerated . So the electromagnetic field are all electrically charged particles surrounded by an electric field . Moving charged particle generates a magnetic field . When the rate of change of charged particles , the EM field is produced.

Electromagnetic field was first discovered in the 19th century , when physicists realized that the electric arc ( sparks ) can be reproduced from a distance , without connecting wires between them.

This led scientists to believe that it is possible to communicate over long distances without wires . The first radio transmitter utilizes an electric arc . This " spark transmitters " and the associated receiver is as interesting for people in the early 20th century as the internet today . It was the beginning of what we now call the wireless communication.

The electromagnetic field is usually generated by the current (alternating AC) in electrical conductors . The frequency of the AC can range from one cycle in thousands of years (at the extreme low) to trillions or quadrillions of cycles per second ( at high temperatures ).

EM is a standard unit of frequency hertz . A frequency of 1,000 Hz is onekilohertz ( kHz ) ; frequency 1000 kHz is one satumegahertz ( MHz ) ; frequency of 1,000 MHz is one gigahertz (GHz).

EM field wavelength is related to frequency . If the frequency f of the EM wave is specified in megahertz and w specified wavelength in meters ( m ) , then the free space , the two are related by the formula :

w = 300 / f

For example , a signal at 100 MHz has a wavelength of 3 m , or about 10 meters . This same formula applies if the frequency in gigahertz and wavelength specified in millimeters ( mm ) . Thus , the signal at 30 GHz will have a wavelength of 10 mm , or slightly less than half an inch.

EM energy field called the spectrum of electromagnetic radiation . In theory , this extends from long wavelengths to short wavelengths.

While the physics of electromagnetism , an electromagnetic field is a field made ​​up of a combination of two related vector fields , namely : the electric field and magnetic field.

Elements of electromagnetic fields

Vector

Vector is a number that has a value and direction , Vector has two methods : Among them :

1 . Graph Method

Parallelogram method ( = 2 vector )

Polygon Method ( ≥ 2 Vector )

2 . Methods Description

Vector multiplication

a. With Scalar Vector Multiplication

b. With Vector Vector Multiplication

i. Dot Product . is an algebraic operation that takes two equal - length sequence of numbers ( usually coordinate vectors ) and returns a single number.

ii. Cross Product ( Sarrus Methods ) . Sarrus method can be used to find the determinant of a matrix berordo up to 3 .

Understanding electromagnetic fields

Law Coloum

Law coloum is the force that occurs between two objects that have overloaded either electrons , protons , and other cargo.

Electric Field Intensity

The intensity of the electric field dalah incident that occurred at a point due to a charge source.

Flux Power ( Intensity )

Is part of the line - a line of strong electric fields that penetrate a surface.

Gauss 's Law

Gauss's law dalah number of lines - electric field lines in a closed field equal to the amount of charge that produces the flux.

Electric potential

If the electric field strength is the magnitude of the vector , the electric potential is a scalar magnitude.

Electric Potential Energy

Style coloum is the vector magnitude , while the potential energy is a scalar magnitude.

Capacitance

Is a measure of the amount of electric charge stored for a predetermined electrical potential .

Inductance

Is the ratio or the ratio of magnetic flux to the current scope which produces the flux . Component ( inductor ) .

Toroidal magnetic field

Ie the magnetic field acting on the toroid.

Magnetic flux

Is the number of magnetic field lines . Which penetrate the surface perpendicularly.

GGL ( electromotive force ) induced

A loop -shaped wire located within the magnetic field and the edges are connected with a galvanometer as shown in the picture , when the wire digerak move in the direction of the magnetic field in and out , the galvanometer needle will turn to the right and to the left.

The movement of the galvanometer needle shows the electric current flowing in the loop . This phenomenon is called electromagnetic induction . The electrical current generated by means demikan called the induced electrical currents.

Some things in terms of the electromagnetic field associated with the factors and supporting elements .