How do you determine if a charge is positive or negative in electrical and magnetical physics?

Question

I was asked how did scientifics determined which charge to be called positive and which to be called negative (+), (-). If you make an experimental measure, you can get either two charges that attract each other or that repel each other, but you don't know which one to call positive and which to call negative. Could it be that this convention comes from the magnetic flux around a magnet? I need this answer urgently, please.

Answer 1

No, the convention just affects the result about the flux, because you have to know a priori what to call positive charge and what not. See this link about the history of the terms:
http://en.wikipedia.org/wiki/Electric_charge#History

Answer 2

In electrical nature, positive charge is something lacking an electron, and a negative charge is something that has an extra electron. But it's totally different in magnetic nature - the (+) or (-) signs in magnetic nature are just polarities like North and South - and it's just an alignment issue, not an electron issue.

So, if you assign (+) to North, then you'll have to assign (-) to South pole. You could try hanging a bar magnet with a string and see which way it turns. The end that points north can be considered the (+) and the other end the (-). A horseshoe magnet will be a little more difficult to determine - you'll need a bar magnet and a horseshoe magnet to determine the polarities. First, do the above string method to find the polarity of the bar magnet, and then mark it, and test the ends with the horse-shoe magnet. The one that repels the (+) end is the (+), and the one that attracts the (+) end is the (-).

Answer 3

The plus and minus convention was first initiated by Benjamin Franklyn to describe the direction of the electric current.
The word charge in gravity is really the mass content of a volume of mass.
In The world of micromasses Charge is used in a different way. It actualy describes the Energy content of a particle mass or elementary particle mass as the electron proton and neutron.
The plus sign and minus sign indicate the direction of the interaction of the electrical particles.
Basically all particle are all subject to the same phenomena.
The neutral and + and - sign only indicate how close the interaction is. when the particles are too close to each other the are not allowed to touch by the rules of gravity hence repulsion occurs regardeless of the polarity of the particles.

The magnetic field occurs because an electric field is moving inside the atoms of a magnetic material. The direction to the magnetic field is not described as plus or minus. The field inside a magnetic material is bipolar and instead of + and - its desiginated as North and south pole.

Answer 4

Both negative and positive flux are just electrical flux . But they are different because atoms in charge have more or less electrons. Those with mere electrons are negative , and without electrons are positive. A electro has elementary negative charge.

Answer 5

As reported by the Ancient Greek philosopher Thales of Miletus around 600 BC, charge (or electricity) could be accumulated by rubbing fur on various substances, such as amber. The Greeks noted that the charged amber buttons could attract light objects such as hair. They also noted that if they rubbed the amber for long enough, they could even get a spark to jump. This property derives from the triboelectric effect.

In 1600 the English scientist William Gilbert returned to the subject in De Magnete, and coined the modern Latin word electricus from ηλεκτρον (elektron), the Greek word for "amber", which soon gave rise to the English words electric and electricity. He was followed in 1660 by Otto von Guericke, who invented what was probably the first electrostatic generator. Other European pioneers were Robert Boyle, who in 1675 stated that electric attraction and repulsion can act across a vacuum; Stephen Gray, who in 1729 classified materials as conductors and insulators; and C. F. du Fay, who proposed in 1733 [1] that electricity came in two varieties which cancelled each other, and expressed this in terms of a two-fluid theory. When glass was rubbed with silk, du Fay said that the glass was charged with vitreous electricity, and when amber was rubbed with fur, the amber was said to be charged with resinous electricity. In 1839 Michael Faraday showed that the apparent division between static electricity, current electricity and bioelectricity was incorrect, and all were a consequence of the behavior of a single kind of electricity appearing in opposite polarities.

One of the foremost experts on electricity in the 18th century was Benjamin Franklin, who argued in favour of a one-fluid theory of electricity. Franklin imagined electricity as being a type of invisible fluid present in all matter; for example he believed that it was the glass in a Leyden jar that held the accumulated charge. He posited that rubbing insulating surfaces together caused this fluid to change location, and that a flow of this fluid constitutes an electric current. He also posited that when matter contained too little of the fluid it was "negatively" charged, and when it had an excess it was "positively" charged. Arbitrarily (or for a reason that was not recorded) he identified the term "positive" with vitreous electricity and "negative" with resinous electricity. William Watson arrived at the same explanation at about the same time.

We now know that the Franklin/Watson model was close, but too simple. Matter is actually composed of several kinds of electricity (several kinds of electrically charged particles,) the most common being the positively charged proton and the negatively charged electron. Rather than one possible electric current there are many: a flow of electrons, a flow of electron "holes" which act like positive particles, or in electrolytic solutions, a flow of both negative and positive particles called ions moving in opposite directions. To reduce this complexity, electrical workers still use Franklin's convention and they imagine that electric current (known as conventional current) is a flow of exclusively positive particles. The conventional current simplifies electrical concepts and calculations, but it ignores the fact that within some conductors (electrolytes, semiconductors, and plasma), two or more species of electric charges flow in opposite directions. The flow direction for conventional current is also backwards compared to the actual electron drift taking place during electric currents in metals, the typical conductor of electricity. The true direction of electric current is a source of confusion for beginners in electronics, and a minority of educators ingnore the standard and instead assume that moving charges are exclusively negative.

Answer 6

A positive element is considered north, a negative is considered south.

A positive element is attracted to the south pole of a magnet, the negative element is attracted to the north pole of a magnet.

Answer 7

relies upon. If by technique of "manage" you recommend use it, then that is anytime you make the most of something digital, like once you turn on a lamp. If truly "manage" skill figuring something out that contains information electric powered fee, then for most individuals that is by no skill.

Answer 8

i just look at it:
if i read + on it, it's positive;
if i read - on it, it's negative;
if i read nothing on it, it's no charge;

This is not a pure joke.
It is conventional issue, they just postulated that electrons have negative charge and protons have positive one. It could be postulated vise versa!