# E Book question

Discussion in 'General Electronics Chat' started by dthx, Jun 9, 2013.

1. ### dthx Thread Starter Member

May 2, 2013
194
14
my nephew and I are going thru the Ebook videos...
In chapter 4.1...the Ebook video says that current always flows from neg to pos....Im sure thats correct...but..
All these years Ive thought that current flows from pos to ground (which I thought is always neg)
Can someone throw a little more light on thattfor us....?
thanks..
D

2. ### tshuck Well-Known Member

Oct 18, 2012
3,527
679
It's the old Conventional Current Flow(The stuff you learned) and the Electron Current Flow(the actual direction current flows, because that's the direction electrons travel). In the beginning, they had to decide on a direction for current, it just turned out to be wrong...

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3. ### dthx Thread Starter Member

May 2, 2013
194
14
Wait a minute...
Now that I review...I remember that there are 2 ways of looking at flow....from pos to neg and vice versa...
Which one should I use?
Pos to neg is "the convential" way....that would seem to be the most common....but the Ebook is using neg to pos...
Can someone lend a hand?
thanks
D.

4. ### dthx Thread Starter Member

May 2, 2013
194
14
Ok..I posted before I saw TShuck's explaination.....
So ....all discussions and math are going to assume neg to pos...?
D.

5. ### tshuck Well-Known Member

Oct 18, 2012
3,527
679
If you are talking to an EE, use Conventional Flow, a physicist, Electron Flow.

The most common is the conventional flow, but it is, of course, incorrectly indicating current direction. Conventional is the most common despite this fact.

6. ### tshuck Well-Known Member

Oct 18, 2012
3,527
679
No, some people will use what they were taught, or are familiar with(Conventional).

Either way, the answers will come out the same, provided you stick to your choice throughout the problem.

As an exercise, try solving a problem using conventional flow and again with electron flow...

7. ### dthx Thread Starter Member

May 2, 2013
194
14
Huh!...........thanks....!
By the way.....how do I get to "the search facility"....I tried clicking on the search field at the top of the Forum Page...and it wasnt the same as what was suggested Dave's post a few above my Q....
I want to check that out before I post a lot of Q's...
There will be others from me as I go thru the Ebook.
D.

8. ### tshuck Well-Known Member

Oct 18, 2012
3,527
679

Also note that Dave's post is a sticky, as such, will always be at teh top of the Forum you are in, "General Electronics Chat", however, yours will not be. As new threads are started, yours goes further and further down the list.

As far as your questions go, it's the reason this site exists, bring 'em on!

9. ### dthx Thread Starter Member

May 2, 2013
194
14
I knew you would say that...thanks..
Is the textbook worth getting and is it still in print....and would I save any dough getting it on Ebay....of does a member want to sell an old copy theyve got hanging around...what do ya think..?
Would you recommend it....does it have some additional quesstons and problems that would be helpful....
d.

10. ### tshuck Well-Known Member

Oct 18, 2012
3,527
679
If you are referring to the ebook, it isn't in print. It is freely available(notice the .pdf link at the top of the pages), so you are free to print it yourself. There are also some websites that will print it for you....they escape me at the moment, perhaps bertus will swing by with some...

The ebook is a good reference, but it does lack some of the mathematical rigor of a college-level textbook, but is great for getting the concepts down!

11. ### MrChips Moderator

Oct 2, 2009
18,168
5,705
Conventional flow vs electron flow has been debated on AAC before.

It is a cultural thing based on what you were taught while growing up, like driving on the left side or right side of the road. Neither is right or wrong as long as you are consistent.

The math does not change with either model.

Think of charge flow as having direction and polarity. A positive charge flowing in one direction has the same effect as a negative charge flowing in the opposite direction. The sign of the potential difference is the same for both cases.

In solid-state electronics such as in the study of diodes and transistors it is common practice to talk about electron-hole pair generation and recombination. A hole is simply a lack of an electron. As the electron moves one way the hole moves in the opposite direction. Hence there is nothing wrong with the concept of a positive charge moving in the opposite direction of an electron.

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