الإضاءة بالكهرباء - الكهرباء في المنزل .. الآلات التي نستخدمها كل يوم وكيف تؤدي عملها

Electric lighting - Electricity in the home .. The machines we use every day and how they work

Electric lighting:

When an object is heated to a certain temperature, it emits a glowing light. For example, the nichrome wire in a toaster emits a weak, red light when this wire is heated by the electricity flowing through it. If you were to see inside an electric iron or grill - while it is hot - you would see that the nichrome wires have glowed in it. This applies to all electric heating devices as well, because each of these devices emits a dim light as well as a large amount of heat.

The electric lamp contains a wire whose properties include converting electricity into heat and light, but it has been designed in such a way that it gives us the maximum amount of light it can. In order for the wire to be able to do this work, it is made very thin, because it has been proven that a thin piece of metal wire glows more than a thick piece when they are exposed to the effect of heat at the same degree, so it is seen that the thin wire needs a much smaller amount to glow than the thick wire. You can verify this for yourself if you hold a needle and a nail in the flame of a match. You will see that the needle glows clearly, because the needle, due to its small size, only needs a small amount of heat to heat up and glow. As for the nail, it glows an unclear glow or does not glow at all because it needs a larger amount of heat to glow. The thin wire of the electric lamp heats up quickly, and glows clearly when electricity flows through it. Since the wire of the electric lamp is thin, it quickly melts and quickly burns. In order to protect it from melting, this wire is made of a special type of metal, called tungsten. Tungsten metal is heated to a melting point. In order to protect tungsten from burning, nichrome metal is covered with a glass bulb from which we evacuate the air. Then the wire cannot burn if the air is removed from it. The air in the glass bulb is replaced by a mixture of other gases that do not allow this combustion.

The bulb is also often made of frosted glass, which reduces the intensity of the light and prevents its brightness.

In order for electricity to flow through the tungsten wires, each end must be connected to the wires coming from the electric company. These connections are located at the base of the electric bulb. One end of the tungsten wire is connected to a small metal plug at the bottom of the bulb, while the other end goes to the copper part with the screws, which is connected to the bulb's inductor.