Electron Gun for a Grade 9 Physics Project?

Click For Summary

Discussion Overview

The discussion revolves around the feasibility of recreating the double slit experiment for a grade 9 physics project, specifically focusing on the challenges of obtaining an electron gun and exploring alternative experiments that are more accessible and safer.

Discussion Character

  • Exploratory
  • Debate/contested
  • Technical explanation

Main Points Raised

  • One participant expresses interest in recreating the double slit experiment but notes the difficulty in obtaining an electron gun and seeks alternative experiments that are less expensive and easier to access.
  • Another participant argues that replicating the quantum-mechanical version of the double slit experiment is impractical and unsafe, suggesting instead the classical version using a low-powered laser or laser pointer, which does not demonstrate quantum effects.
  • A third participant mentions the possibility of using cathode ray tubes from old TVs to obtain an electron gun, but raises concerns about the safety and practicality of opening the vacuum section of the tube.
  • A later reply warns against the dangers of attempting to open an old CRT glass envelope, highlighting the risks of implosion and potential hazards involved.

Areas of Agreement / Disagreement

Participants generally agree on the impracticality and safety concerns of using an electron gun for the experiment. However, there are differing opinions on the feasibility of alternative methods to demonstrate the principles of the double slit experiment.

Contextual Notes

Limitations include the need for a vacuum environment for electron beams, the safety hazards associated with working with CRTs, and the lack of consensus on a suitable alternative experiment that effectively demonstrates the intended concepts.

Jake2003
Messages
1
Reaction score
0
I am in grade 9 in the IB curriculum and next year I have to do something called a "Personal Project" where I have to make something and explain why I did it. I would like to recreate the double slit experiment. However, I have to obtain a electron gun and they are quite hard to come across. So I was wondering whether anyone on here has any idea how to obtain one or a better experiment to recreate that wouldn't require something as expensive or hard to get?
 
Physics news on Phys.org
I am sorry to have to say that there is no practical and safe way for you to replicate the quantum-mechanical version of the double-slit experiment.

It is realistic to try replicating the classical version of the experiment, which demonstrates the wave nature of light and was first done by Thomas Young early in the 19th century. For that, you could use a readily available low-powered laser, even a laser pointer will be good enough. However, that's not showing the quantum mechanical effect in which the interference pattern is built up by individual photons arriving over time - for that you would need both a source that generates single photons at a time and a detector capable of detecting and recording the arrival of a single photon.

Working with electrons is even more difficult. First, they're electrically charged and interact with random air molecules so you would need to enclose the beam in a hard vacuum. Second, an electron beam poses a significant radiation hazard.
 
  • Like
Likes   Reactions: berkeman
Old TVs have cathode ray tubes. The screen is made of thick leaded glass to block most of the x-rays. If you somehow opened the vacuum section, you could put a slit between one of the electron guns and the screen. But, I don't know how you would be able to close it up again with a good vacuum seal. There must be a way that the TVs were originally assembled, using a vacuum pump. Maybe ask someone who used to make these TVs.
 
Khashishi said:
If you somehow opened the vacuum section
We're getting into dangerous discussion territory here, so the thread will be closed now. It's pretty hard to "open" an old CRT glass envelope without initiating an implosion. And those are messy and dangerous. Do not ask me how I know this.
 

Similar threads

  • · Replies 26 ·
Replies
26
Views
2K
  • · Replies 26 ·
Replies
26
Views
2K
  • · Replies 28 ·
Replies
28
Views
8K
  • · Replies 11 ·
Replies
11
Views
3K
  • · Replies 4 ·
Replies
4
Views
1K
  • · Replies 20 ·
Replies
20
Views
2K
  • · Replies 17 ·
Replies
17
Views
4K
  • · Replies 7 ·
Replies
7
Views
2K
  • · Replies 6 ·
Replies
6
Views
2K
  • · Replies 33 ·
2
Replies
33
Views
4K