CRT High Voltage: Why Does It Need It?

AI Thread Summary
A cathode ray tube (CRT) requires high voltage to ensure the cathode ray gun has sufficient energy to emit electrons. This high voltage facilitates the conversion of potential energy (PE) into kinetic energy (KE) as electrons travel through the tube. The acceleration of these electrons is crucial for producing light when they strike the screen. The voltage must be sufficiently high to generate photons in the visible spectrum. Understanding these energy conversions is essential for grasping CRT functionality.
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Why does a cathode ray tube (CRT) require a high voltage to operate?
 
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What part of the CRT circuitry are you referrring to?
 
the input voltage/energy required, so that the cathode ray gun has enough energy to fire the electron/cathode ray.
 
Think of the energy conversions that occur
PE(eV) to KE(as electrons fly through the tube) to light energy as the electrons strike the screen.
The accelerating voltage(V) must be big enough such that photons in the required visible region of the spectrum are released.
 

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