Does Voltage Work Against Electron Movement?

  • Context: High School 
  • Thread starter Thread starter kjeldsmark
  • Start date Start date
  • Tags Tags
    Law Ohm's law Voltage
Click For Summary

Discussion Overview

The discussion revolves around the interpretation of voltage and its role in the movement of electrons within electrical circuits. Participants explore the phrasing used in an article regarding voltage as "pressure" and whether this analogy accurately represents the physical concepts involved. The conversation touches on theoretical understanding, educational approaches, and the translation of technical terms.

Discussion Character

  • Conceptual clarification
  • Debate/contested
  • Meta-discussion

Main Points Raised

  • Some participants question the use of the term "against the voltage pressure," suggesting it may misrepresent how voltage functions in driving electron movement.
  • Others propose that voltage can be seen as a potential difference that requires energy to move charges, likening it to a water pump moving water against gravity.
  • A participant expresses concern that the analogy of voltage as pressure could lead to misconceptions, advocating for a clearer association with work or energy instead.
  • Some participants highlight the importance of simplifying concepts for educational purposes while cautioning against oversimplification that could lead to misunderstandings.
  • A later reply emphasizes the need for careful translation of technical terms to avoid perpetuating misconceptions in different languages.
  • One participant reflects on the challenges of teaching complex scientific concepts and the balance between accessibility and accuracy in explanations.

Areas of Agreement / Disagreement

Participants express differing views on the appropriateness of the "voltage pressure" analogy, with no consensus reached on whether it accurately conveys the underlying physics. The discussion remains unresolved regarding the best way to explain voltage in educational contexts.

Contextual Notes

Participants note that the analogy of voltage as pressure may not align with the mathematical descriptions of electrical phenomena. There is also mention of the potential for confusion when translating technical terms between languages.

Who May Find This Useful

This discussion may be of interest to educators, students, and translators involved in teaching or communicating concepts related to electricity and voltage.

  • #61
Ok I understand your concern , I too am not a fan of mathematics mainly because I'm not that good at it.
Just to start this I want to say that the maths and the images and schematics in your head of how it works go hand in hand.I agree that it is good and even necessary to understand how does it work, but when you will need to make a physical device you will need some accurate measurements and sizes and dimensions and then mathematics will become involved.
Einstein realized that the atomic bomb is possible because he was a man of great mind yet it took much more physiscists and Oppenheimer as the leading one to calculate all the details to make a real physical example of that imagined bomb.

Second of all when we get down to the very small , say quantum level it becomes really really troubling to imagine and have a picture in your head about how it works , mainly because you can't see it , and every analogy every story about how atoms look or behave isn't a perfectly accurate picture it just goas as far as it can , and here maths also isn't the full answer it describes the interaction in detail but that doesn't make you suddenly an observer of atomic stuff.
I would say that in certain physics areas due to the fundamental limitatios of this world we live in no way is good enough to have this " gut" feeling you are talking about.

Why do you think there is something magical inside a transistor ? It's nt so much about smaller current controling larger one in a sense that you would think that you can move a big rock with a tiny little stick , its rather applying that small current into the right place.
let me make an analogy , maybe not a perfect one but from what i ca tell you like them.
imagine the BJT as a dam on a small river made of sand and soil.the damn keeps the river at a certain height so the water before the dam has a pretty high potential and that would be our collector current. Now the water even though could destroy the dam and wash it away doest do that it just sits there.Now take a little side stream and apply it to the right place inside them dam so that it washes away the soil and makes it wet , now the large water mass is able to push the dam aside and run free.

in a transistor bjt, the small base current isn't physically pushing the large collector current, it just makes the transistor conducting from a non conducting state and so the larger current can flow.
 
Physics news on Phys.org
  • #62
kjeldsmark said:
And regarding 'learning style' I feel the same way as Mr. WJB:

"When I went into engineering school, I found it extremely odd that there were still no good explanations of bipolar transistors. Sure, there were detailed mathematical treatments. Just multiply the Base current by "hfe" to obtain the Collector current. Or, treat the transistor as a two-port network with a system of equations inside. Ebers-Moll and all that. But these were similar to black-box circuits, and none of them said HOW a transistor works, how can a small current have any effect on a larger one? And nobody else seemed curious. Everyone else in the class seemed to think that to memorize the equations was the same as learning concepts and gaining understanding of the device. (R. Feynman calls this the Euclidean or "Greek viewpoint;" the love of mathematics, as opposed to the physicists' "Babylonian viewpoint" where concepts are far more important than equations.) I'm a total Babylonian. For me, math is useless at the start, equations are like those black box Spice programs which might work great, but they don't tell you any details of what's happening inside a device in the real world. I can learn the math, but that just means I can run a "mental spice program" without needing any computer, and I still don't know how transistors work. First tell me what "Transistor Action" is all about. Show me animated pictures, use analogies. Only after I've attained a visual and gut-level understanding of something, only then is the math useful to me for refining it and adding all the details. However, for me the math alone is not a genuine explanation. Math is just a tool or a recipe, a crutch for those who want nothing except the final numerical result, and it certainly does not confer expert knowledge."

(http://amasci.com/amateur/transis.html)

I have to say that William Beatty and / or his tutors must just have been out of their depth about the mechanism which makes a transistor work. Of course there is a 'good' (accurate) description in many textbooks. The point is that the description cannot be reduced to a trivial level whilst remaining accurate. How is that 'unsatisfactory'? Life is not full of simple solutions to all problems. If someone can't understand the full description then they are either limited by the level of their basic ability or by how much they are prepared to work at it. (Like weight lifting and triathlons).
That statement reflects either a sloppy attitude or an over estimate of his understanding of the topics he is applying to. It's not a matter of 'the Maths of the Ideas'. You need both, if you want to understand advanced Science to a level where you can predict and synthesise usefully. If you didn't need the Maths, then you could get a higher Physics degree on the strength of what they tell you on the TV Science programmes.
Do you really believe that this computer you are using, at the moment, was made to work by people who just waved their arms about and had a 'comfortable' feeling that they grasped how solid state devices work? Maths is not "just a crutch". It is a vital extension to everyday language which allows people to manipulate and communicate ideas and relationships that are way beyond the limits imposed by English. A picture speaks a thousand words - very true - but there is no satisfactory verbal description that can deal with even the simple operation of changing the subject of a linear algebraic equation to get a numerical answer to a simple electrical problem. Try describing, concisely, the Fourier transform in simple words.
 
  • #63
another thing people are not ready to wait these days, eberyone needs everything on the spot.understanding and knowledge including , but the thing is understanding and " gut" feeling comes only after a while , after many hours spent learning and trying to undersand stuff.
I may hate that myself but sadly it's the truth.

So paraphrasing Jack Nicholson, I want to ask you , Can you handle the truth? :D
 
  • #64
This thread has degenerated into something completely different and is no longer on the physics. It is now done.

Zz.
 

Similar threads

  • · Replies 57 ·
2
Replies
57
Views
14K
  • · Replies 28 ·
Replies
28
Views
4K
  • · Replies 8 ·
Replies
8
Views
3K
  • · Replies 28 ·
Replies
28
Views
4K
  • · Replies 20 ·
Replies
20
Views
3K
  • · Replies 8 ·
Replies
8
Views
10K
  • · Replies 13 ·
Replies
13
Views
7K
Replies
1
Views
2K
  • · Replies 12 ·
Replies
12
Views
7K
  • · Replies 2 ·
Replies
2
Views
2K