Electric charge is the property characterizing ability of a body to participate in electromagnetic interactions and to induce (to create) electric field. There are two types of charges: positive and negative. Charges are measured in pendants, one pendant is a size of a charge which passes in 1 second through the cross section of any conductor, at current in 1 ampere. Charged bodies are attracted by Raznoimenno to each other, the same loaded – make a start. How to receive a positive charge?
It is required to you
- - glass stick;
- - piece of silk matter.
Instruction
1. Since ancient times it was known that if to rub a piece of amber about wool, then it begins to attract some very easy objects. Such "demonstration experiments" made a great impression on people though, of course, they could not explain the nature of this phenomenon.
2. Many centuries later, namely in 1729, the French scientist Shar Francois Duf by practical consideration found out that there are two types of charges. The first of them was formed when rubbing a glass subject about silk, the second – when rubbing a piece of pitch about wool. A little later famous Benjamin Franklin entered concepts of a "positive" and "negative" charge.
3. Repeat experiment of receiving a positive charge in house conditions. For this purpose wrap up in a piece of silk a glass stick (as a last resort, any glass subject of a cylindrical form, for example, a test tube, the laboratory pipette) and several times vigorously carry out by it backwards-forward so that the stick rubbed about silk. No visible changes, naturally, happens.
4. How to check that the stick was electrified, that is received some charge? For this purpose bring it to in advance cut paper pieces. You will see that these pieces will immediately be attracted to glass. Though before you rubbed a stick about silk, they to it were not attracted!
5. You can obtain also other clear proof for the fact that the glass stick got a charge. There is a special device – the electroscope. If to touch with a polished stick one end of its metal core, then the thinnest leaflets of a foil suspended by other end of a core, to deviate in the parties. Because they received a part of the charge which flowed on them from a stick via the pin. It is easily possible to understand that otherwise leaflets of a foil would remain motionless.