28 Apr How does a fluorescent tube work?
All of you must have seen a fluorescent tube light at home, school or other places. Even though other lights are coming through, fluorescent tube gives you bright yet soothing light at reasonable low power consumption. Ever wondered how a fluorescent tube giving us the bright light? Do you want to know its working principle? Your physics tuition will just do that for you. So, let us understand the basic working principles of fluorescent tube light. In today’s physics tuition you will learn how a fluorescent tube light works.
Man has been using artificial lighting since old times. The revolutionary invention in this field was that of electric bulb in 1878 by Thomas Edison. By 1930, the scientists of America and Europe have developed the wonderful fluorescent tube.
A fluorescent tube consists of a long tube made of glass and coated inside with some fluorescent materials. There are two tungsten electrodes fitted at the ends of this glass tube. The glass tube is evacuated and then filled up with a small quantity of argon gas and mercury. When the connection of the tube is made with an electric line, the electrodes made of tungsten get heated up thereby starting to produce electrons. The electrons, thus produced then collide with the atoms of mercury and generate visible and ultraviolet light. Ultraviolet light on colliding with fluorescent materials generate visible light. These generated lights may have different colors depending upon the fluorescent matters used inside.
These tubes are coated with calcium tunstate to produce blue light. Similarly, a calcium silicate coating produces light of pink color, whereas green light is produced with zinc silicate. Fluorescent tubes are useful sources of light producing light of very high efficiency at relatively low electric consumption. Normally, fluorescent tube can be lighted for 40 hours with one unit of electricity. It means that it has wattage of 40 watts. We hope you enjoyed this lesson from physics tuition. We will be back with more such interesting findings in our next physics tuition.