Cathode Ray Tube: Positive End & Electrons Explained

In summary: That doesn't make any sense either. An electron will move from a low electrostatic potential to a high potential. It has nothing to do with something being negative or positive. I could have the electrons coming out of a conductor at -10 V and it will still be "attracted" to a conductor at - 5 V, because that latter conductor is at a higher potential. The difference in the potential will create a potential gradient, thus, electric field.At some point, one should stop getting bogged down with the "name" given to something. If you understand what is going on, you can call it anything you like.
  • #1
pivoxa15
2,255
1
Why is the end of the hot filament where negatively charged electrons are being fired called the cathode end. 'cat' in chemistry means positive, I assume the same goes in physics as well?
 
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  • #4
cathode is called cat or positive because it is emitting or "losing electrons" thus making it positive or cat
 
  • #5
remember thermo ionic emission
 
  • #6
hustleberry said:
remember thermo ionic emission

What is thermo ionic emission?
 
  • #7
Thermionic emission is the emission of charged particles from a charged surface (usually metal), which is caused by the vibration energy of the particles overcoming the electrical potential holding them to the surface. An example of this would be your cathode ray tube where a charged filament is heated (by passing a large current through it), the electrons on the surface of the filament (remember charge always resides on the surface of a conductor) gain enough thermal energy to 'break free'.

For more detail google: Thermionic Emission
 
  • #8
hustleberry said:
cathode is called cat or positive because it is emitting or "losing electrons" thus making it positive or cat

So that is the main reason. The receiving end is receiving the electrons hence will be made more negative so that end is called the anode.
 
  • #9
pivoxa15 said:
So that is the main reason. The receiving end is receiving the electrons hence will be made more negative so that end is called the anode.

That doesn't make any sense either. An electron will move from a low electrostatic potential to a high potential. It has nothing to do with something being negative or positive. I could have the electrons coming out of a conductor at -10 V and it will still be "attracted" to a conductor at - 5 V, because that latter conductor is at a higher potential. The difference in the potential will create a potential gradient, thus, electric field.

At some point, one should stop getting bogged down with the "name" given to something. If you understand what is going on, you can call it anything you like.

Zz.
 

What is a cathode ray tube (CRT)?

A cathode ray tube is a type of vacuum tube that was used in older television and computer monitors. It works by using a stream of electrons to create an image on a fluorescent screen.

What is the positive end of a CRT?

The positive end of a CRT is the anode, which is a positively charged electrode that attracts the negatively charged electrons emitted from the cathode.

How do electrons work in a CRT?

Electrons are emitted from the cathode and accelerated towards the anode by an electric field. As they travel, they pass through a series of focusing and deflecting electrodes, which control the path of the electrons and ultimately create an image on the screen.

Why are CRTs not as commonly used anymore?

CRTs have largely been replaced by newer display technologies such as LCD and LED because they are more energy efficient, produce higher quality images, and are smaller and lighter in size.

Are there any potential health risks associated with CRTs?

There have been concerns about exposure to electromagnetic radiation from CRTs, but studies have found that the levels emitted from CRTs are well below the recommended safety limits. However, prolonged exposure to the flickering image on a CRT may cause eye strain and headaches for some individuals.

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