Electricity Poll: which way were you taught?

[zoobyshoe]

In which direction did your physics text teach electricity flows?

Please mention the country in which the school where you learned this was located. I think there may be differences based on location in the world.

 

[Pythagorean]

Us, positive to negative

 

[Pythagorean]

Of course with the misnomer that electrons actually travel (slowly) opposite the direction of current.

 

[Monique]

Well, that was taught in high school a looooong time ago. The electrons move from - to +, but the current is defined by the positive charge, so that would then appear to move in the other direction (NL). Did I learn it correctly?

 

[BobG]

I was taught two different methods, so I answered the first way I was taught.

In military tech school, I was taught negative to positive.

In college, I was taught positive to negative.

 

[rollcast]

In Technology we're taught conventional current and that what we use for all our electronics work. However in physics we learn about both conventional current and electron flow. However the only time you have to use electron flow is if the question specifically asks about electrons.

 

[I like Serena]

I was taught two different methods, so I answered the first way I was taught.

In military tech school, I was taught negative to positive.

In college, I was taught positive to negative.

Just to make sure, were you taught that "electricity" or perhaps "current" flows from the negative pole to the positive pole?
Or were you taught that "electrons" or perhaps the "electron flow" flow(s) from the negative pole to the positive pole?

Which word was used, exactly, on military tech school?

 

[nsaspook]

I was (non school) taught electrical energy moves from source to load and that the physical effects on the medium of transmission are secondary effects caused by that movement.

I still have my first textbook on electricity "Drake's Cyclopedia of Radio and Electronics 11ed 1943" from a relative who was in the signal corp in WW2.

 

[fluidistic]

Well, that was taught in high school a looooong time ago. The electrons move from - to +, but the current is defined by the positive charge, so that would then appear to move in the other direction (NL). Did I learn it correctly?

Same here. I'm not 100% sure but I think I've learned this in France, Canada (Québec) and Argentina.

 

[Integral]

US Navy tech schools teach electron flow. They let us know that some places teach the opposite but choose to teach electron flow because it is physically real. Note that this was 40yrs ago, we did spend 3 weeks on transistors so learned about holes and current flow through solid state devices.

 

[BobG]

Just to make sure, were you taught that "electricity" or perhaps "current" flows from the negative pole to the positive pole?
Or were you taught that "electrons" or perhaps the "electron flow" flow(s) from the negative pole to the positive pole?

Which word was used, exactly, on military tech school?

US Navy tech schools teach electron flow. They let us know that some places teach the opposite but choose to teach electron flow because it is physically real. Note that this was 40yrs ago, we did spend 3 weeks on transistors so learned about holes and current flow through solid state devices.

Same as Integral (except only 30 years ago). They did point out the flaws with this idea (how long an electron actually takes to go from the battery to the starter using DC current, for example). Negative to positive was simply a convention they used when teaching.

 

[Astronuc]

I think in high school it was mentioned that electrons flow from - to +, but current flows from + to -, as in + from the battery terminal, around the circuit to the - terminal. There was some decoupling of electrons and current, which I didn't clear up until university where finally someone explained the convention that current is the flow of + charges, whereas negative charges (electrons or - ions) flow opposite the current.

I think in high school chemistry were referred to flow of electrons as current, which contributed to some of my confusion when I learned that current was in the direction of the flow of positive charges. I also found it confusing since I knew that electrons flow in electrical circuits and positive charges didn't flow through the circuitry. Of course, atoms can diffuse in solids, but not very quickly at low temperature.

 

[lostcauses10x]

Negative to positive. Showed a vacuum tube with a paddle wheel as how this was found out. USA.

Might be fun to find one of them tubes or make one.

If I get a chance I will find on of my old books and see what it says, prior to 1900

Edited to add a link to such a tube.
https://wiki.brown.edu/confluence/display/physlecdemo/7B35.50+Electron+Momentum+Paddle+Wheel

 

[Snicker]

Are you talking about voltages? Positive charges (which indicates the direction of current) accelerates towards lower electric potentials. So I suppose positive to negative. Also, United States.

 

[lostcauses10x]

The history of this problem come from way back to electrostatics. The + and - is just a notation use to designate a "charge, such that +,+: and -,- of course repelled, and unlike charges attracted. When way back when, it was said to be that + moved to - when a conductor was attached to the different charges, it was a guess.

When later experiments showed the opposite, well this is the nature of such questions today.

 

[Ivan Seeking]

I think I would have to go back to Cub Scouts for my first exposure here. No doubt this was discussed as current [hole] flow. At any point after that, my best recollection is that I was aware of both concepts. One of my science fair projects was a Van de Graaff generator, which clearly conveys the concept of electron flow. That was in the ninth grade, but I worked from dad's college physics books, so it's hard to be sure of what was taught in class.

Zooby, I think you needed at least a third option, so I didn't vote.

 

[turbo]

I was self-taught in vacuum-tube electronics, and traced everything from positive to negative, for some reason. Got a power-supply circuit that is rectified and feeds a B+ rail, and trace from there. It worked.

 

[Pythagorean]

I wasn't actually taught that "electricity flows" though; I was taught current does. Electricity isn't really a quantity with units like current is, it's more like the general name for the phenomena.

 

[zoobyshoe]

I think I would have to go back to Cub Scouts for my first exposure here. No doubt this was discussed as current [hole] flow. At any point after that, my best recollection is that I was aware of both concepts. One of my science fair projects was a Van de Graaff generator, which clearly conveys the concept of electron flow. That was in the ninth grade, but I worked from dad's college physics books, so it's hard to be sure of what was taught in class.

Zooby, I think you needed at least a third option, so I didn't vote.

Yes, I didn't anticipate any situations where someone could say they were taught both.

I wasn't actually taught that "electricity flows" though; I was taught current does. Electricity isn't really a quantity with units like current is, it's more like the general name for the phenomena.

You're right. The word "electricity" should be replaced with "electric current". A specific direction usually has to be attributed to DC so there's some sense of what's alternating when AC is introduced.

 

[I like Serena]

I think the question in which direction "electric current" flows is a bit ambiguous.
Are we talking about "conventional current" or "electron flow"?
I have also been taught both.

But suppose you have the schematic of an electrical circuit.
In which direction would you draw the arrows representing the current?
From the plus pole (high voltage) to the minus pole (low voltage) or vice versa?

 

[BobG]

Yes, I didn't anticipate any situations where someone could say they were taught both.

Oh, for crying out loud!

If it was the first way you were taught, you flip the light switch on! For all subsequent ways you were taught, leave the light switch alone. The only person that gets to flip the switch down is the counter (Zooby). It's the only possible way we'll know for certain!

 

[AlephZero]

For those who are sure they know the "right" answer (whichever you think is right), see http://amasci.com/amateur/elecdir.html

Or see http://amasci.com/miscon/elect.html for a bigger picture of how to confuse students about electricity.

 

[wukunlin]

I was told that we model electrons pop out of the positive terminal to the negative, but when they found out in reality it is the opposite no one bothered to change all the textbooks

 

[Ivan Seeking]

For those who are sure they know the "right" answer (whichever you think is right), see http://amasci.com/amateur/elecdir.html

Or see http://amasci.com/miscon/elect.html for a bigger picture of how to confuse students about electricity.

I was quite shocked the first time I calculated the electron drift velocity in a wire given a nominal dc current.

 

[rollcast]

I was quite shocked the first time I calculated the electron drift velocity in a wire given a nominal dc current.

We worked it out in physics last week and its something like 24 hours to go through 1 metre of wire IIRC.

 

[netgypsy]

Taught to draw the current arrows in the direction a positive charge would flow IF it flowed. And that this was just a convention so everyone would know what the arrows meant.

I do recall chemistry teachers talking about the fact that convention for flow in chemistry was the opposite as that taught in physics but I taught both and both seemed totally logical so I never did figure out what her problem was with it?

I'm thinking it was because the cathode and a cation were opposite in charge, but they are different things so its just a matter of being careful to read whatever convention the materail is using.

 

[Chi Meson]

I teach students simultaneously that "current" is from + to - , while electrons (which are the only things flowing in solid conductors) drift from - to + .

I like to point out that it's all Ben Franklin's fault for calling the glass rod "Positive."

(I want to go back in time so I could ask "Are you sure?"

and he would reply

"Yes, positive.")

 

[zoobyshoe]

I like to point out that it's all Ben Franklin's fault for calling the glass rod "Positive."

(I want to go back in time so I could ask "Are you sure?"

and he would reply

"Yes, positive.")

Great joke! At least, I got a charge out of it.

 

[turbo]

Great joke! At least, I got a charge out of it.

 

[Pythagorean]

Great joke! At least, I got a charge out of it.

pardon my reluctance to laugh, the charge wasn't moving enough for me.