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Conductors - Some basic facts about electrons - The movement of electrons in the atom .. Electronics

Conductors

Conductors are used to transmit current to the point where it is required to be transmitted. They also allow the free movement of electrons from their orbits in their atoms to the orbits of another neighboring atom, so that a specific electric current results from this movement of electrons and their transfer from one atom to another in the material (5). Silver and copper are considered good conductors because they allow the current to pass completely freely. Copper is used to transmit electricity and can be drawn into wires that can be twisted to form switches, or used to carry current (7).

Insulators

We may need to direct the current in a specific path or to prevent it from passing in another path. Insulators help us accomplish this. An insulator is a material that does not allow the electric current to pass through it easily, and a good insulator.

E - Composition of current from the ease of exchanging electrons.
6 - Conductors send the current wherever we want.
7 - Covering the wires with insulating materials.

8 - Solid insulating parts.

It does not allow the orbits to exchange electrons with each other, nor for the electrons to move from one atom to another. For this reason, it does not allow the current to pass through it. Glass, mica and rubber are considered good insulators. There are also many other insulating materials. Rubber, polyvinyl chloride, cotton, silk, enamel and other insulating materials are used to cover the wires to prevent them from touching each other or touching any adjacent metal parts through which the current is not wanted to pass (7).

Glass, mica, ceramics, phenolic plastics and other solid insulating materials are used to carry and insulate conductive parts inside switches, valves, transistors, capacitors and other components used in the manufacture of various electronic devices (8).

The choice of the most appropriate type of insulator depends on the nature of the work being performed. If the wires are to be covered and insulated, the insulator used must be thin and flexible, while to achieve other purposes we need materials that operate at high voltages or high temperatures.

Primary Cells

We have previously mentioned that potential differences can be produced using methods, and primary cells or batteries are considered one of the most important chemical means used for this. If two plates, one of zinc and the other of carbon, are placed in a solution of ammonium salt (9), the chemical energy is converted into electrical energy. This is because the atoms of the ammonium salt solution remove incomplete atoms from the zinc plate, i.e. atoms that are missing some electrons, each atom leaves two electrons in its place on the zinc plate. As a result, the number of electrons on the zinc plate increases, and thus the value of the charge it carries increases.

9 - A simple cell for generating electromotive force by chemical means.

10 - A commonly used dry cell.

On the other hand, the removed zinc atoms enter the solution as positive ions, i.e. atoms that have lost some of their electrons. These ions continue to exit until the solution is saturated and refuses to accept any of them, thus becoming positively charged, and the carbon plate immersed in it and in contact with it also becomes positively charged.

In this case, a potential difference, or electromotive force (E.D.C.), arises between the zinc and carbon plates. If they are connected from the outside with a metal wire, electrons flow through it. Chemical reactions continue to supply the zinc plate with excess electrons until the cell is completely discharged.

The commonly used "Leclanche" cell consists of a zinc vessel that plays the role of the negative electrode of the cell and a carbon rod placed in the center of the vessel that forms the positive electrode (10). The carbon rod is then surrounded by a powder of carbon and manganese dioxide, whose molecules combine with hydrogen molecules to produce water and prevent the accumulation of gas atoms. Hydrogen. The electromotive force of this cell is 1.5 volts.