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Last updated date: 28th May 2024
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The Bulb


An incandescent bulb gives us light and an incandescent lamp or incandescent light globe is an electric light with a filament wire that is heated until it glows. The current is supplied to the filament by the means of wire or the terminals embedded in the glass. A socket bulb generally provides mechanical support and electrical connections as well.

The bulbs which are incandescent are manufactured in a wide range of sizes. That is the output of light and voltage ratings that is from 1.5 volts to about 300 volts. 

As a result, we can say that the incandescent bulb became widely used in household and commercial lighting that is for portable lightings such as lamps on tables and the car headlamps and flashlights and for advertising and decorative lighting.

Light Bulb

A bulb that generally gives out or we can say it emits light. There are different types of bulb in varieties. The bulb which is the filament one is used, for example, in a car headlight or for lighting in houses purpose as well.  There are also lights that are fluorescent and they are energy saving in nature. Another type is an LED is a light-emitting diode. These are getting more popular nowadays in the day to day life. For example, we can see an array of LEDs in brake lights of vehicles.

A simple traditional light is an incandescent bulb. This is such a basic technology that we take this almost for granted but if we delve into the quantum physics that is behind it we find that something amazing is happening with it.

The principle that is operating behind the light bulb is very simple: we run an electric current through a thin filament which causes it to get hot. The objects that are hot generally emit light so the bulb glows. The higher the temperature the more intense the glowing of the bulb happens and the more "white" the light that comes out. So we can say that if we get the filament hot enough then we get a bright source of light at wavelengths through the whole visible region of the spectrum.

LED Light Bulbs

As we have seen that the high temperature is the reason for the lighting of the bulb. The Heating of a filament to the temperature that is necessary for air will cause chemical reactions that quickly destroy the filament. This can be avoided by usually putting the filament in a glass bulb with the air either pumped in it away or in a higher-wattage bulb replaced with an inert gas for example like argon. This is why if we put a light bulb in a microwave oven sometimes it produces cool flickering colours that represent the gas inside makes a plasma.

The light which is emitted by a hot object is known as "blackbody radiation," and has some interesting properties which are simple. The colour of the light does not strongly depend on the properties of the material being heated that are just its temperature. And the spectrum of light or the intensity of the light emitted at various wavelengths usually takes the form of a broad peak whose wavelength changes location in a fairly simple way. 

This makes the spectrum surprisingly difficult to explain though. As we have mentioned when writing about Sir Einstein's truly radical contribution to Physics, the most obvious approach to this problem generally produces disastrous results. Sir Max Planck was able to explain the spectrum in 1900 but he had to resort to maths for a desperate trick that is assigning an energy characteristic to the light-emitting material. This is the idea Sir Einstein picked up in 1905, which is introducing what we now call photons in order to explain the photoelectric effect. These LED models are inevitable to the development of quantum mechanics in all its glory.

Halogen Bulbs

A lamp of halogen is also sometimes called a halogen of the tungsten that is quartz-halogen or we can say quartz iodine lamp is a lamp that is incandescent. That consists of a filament of tungsten which is sealed into a compact transparent envelope. The envelope is filled with a mixture of a gas that is inert and a small amount of a halogen gas such as bromine or iodine. This allows the filament to operate at a temperature that is higher than a standard incandescent lamp of similar power and life operating. This is also said to produce light with higher luminous efficacy and temperature colour.

FAQs on Bulb

1. What is the Principle of an Electric Bulb?

Ans: The principle that is operating behind the light bulb is very simple: we run an electric current that is through a thin filament. which generally causes it to get hot. The hot objects emit light so the bulb glows. The light which is emitted by an object which is hot is known as "blackbody radiation," and has some interestingly simple properties.

2. Explain What a Bulb is in Electricity.

Ans: An electric bulb is a device that produces light when electricity is passed through its terminals. The bulb has two thick wires that are contacted in the centre with a thin wire attached between them. This thin wire is known as filament. A bulb is said to be fused if the filament usually gets broken. The bulb that is fused doesn't glow.

3. Explain How a Bulb Works.

Ans: In an incandescent light bulb, electricity is turned into light by sending the electric current through a thin wire known as a filament. The electrical filaments are made up mostly of metal that is tungsten. The resistance of the filament heats the bulb very easily. Eventually, the filament gets so hot that it glows that too producing light.

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