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shivanshu
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Why cathode rays which consist of electron that do not have any colour are seen as a colourful ray of light in a discharge tube??
That means that we cannot see the cathode and anode rays without any phosphor coating?berkeman said:Welcome to the PF.
Do you mean on the face of a Cathode Ray Tube (old-style television screen)? If so, phosphor coatings are used on the CRT faceplate to generate the colors...
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shivanshu said:That means that we cannot see the cathode and anode rays without any phosphor coating?
We are all saying that an electron beam traveling in a vacuum does not give off a color of visible light. The energy from the accelerated e-beam can be transferred to phosphor or to gas molecules to cause visible light to be given off.shivanshu said:I still can't understand please be more explanatory...
shivanshu said:I still can't understand please be more explanatory...
The coloured beam in a discharge tube is caused by the emission of light from excited atoms or ions. When an electrical current is passed through the gas inside the tube, it causes the atoms or ions to become excited and emit light at specific wavelengths, resulting in a coloured beam.
Different colours appear in a discharge tube because each element or gas has a unique set of energy levels. When the atoms or ions in the gas are excited, they emit light at specific wavelengths, which determine the colour of the beam. For example, neon gas produces a red-orange colour, while mercury gas produces a blue-green colour.
Yes, the colour of the beam in a discharge tube can be changed by using different gases or adding elements to the gas mixture. Each gas or element will have its own unique set of energy levels, resulting in a different coloured beam when excited.
The colour of the beam in a discharge tube can be affected by several factors, such as the type of gas or element used, the voltage and current applied to the tube, and the pressure and temperature of the gas inside the tube. These factors can influence the energy levels of the atoms or ions and therefore impact the colour of the emitted light.
No, the coloured beam in a discharge tube is not harmful. It is a result of low-pressure gas being excited by an electrical current and does not emit any harmful radiation. However, it is important to handle the discharge tube with caution as it does contain high voltages and can cause harm if not used properly.