Which way does electricity flow?

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So Iam watching a film that states that electrons will always try to get from a negatively charged body, to one that is positively charged.
So why therefore, does a diode pass electricity freely from positive to negative?

No.
Link: Diodes

In keeping with the intent of the original poster. It is because of a simple difference of terminology. In a physics discussion of electricity, we are talking charge (positive vs. negative) in a sub-atomic sense. The electrons (which have a negative charge) flow to where they are needed (i.e. atoms that are electron deficient at the moment and have a positive charge).

In electronics, we have a reversed terminology. The electron flow comes from the "hot" side... it has a positive charge (which is negative because it is electrons)... If it makes it easier, consider it pressure... the hot side of a circuit has electrons waiting, like water pressure. The negative side has negative pressure (an electron vacuum, as it were), and is waiting for the electron flow. It is referred to as negative because it has no charge...

It may help to think of it in a binary sense. Hot or positive is 1. ground, or negative is 0.

It was explained to me that the positive side of a circuit is called such because they are using the affirmative of positive, not the charge and negative is not a reference to charge, but likewise the ngative form of the verb to be.

I hope this helps...it is nebulous without getting into many other things...

electricity is the flow of electrons.

Electrons flow from where there are too many electrons ( negative charge) to where there are too few (positive charged).

Thats what direct current is. Electrons moving through a wire from one pole of the battery to the other, and doing work (ie lighting the flashlight bulb) on the way. The physical direction of the flow of electrons never changes. Its one directional.

Appliances like flashlights use simple direct current.

But the electriciy coming through the city wires to your house are on alternating current.

Alternating current is also negative to positive, but the postive target that the electrons are drawn to flip flops in physical position constantly between to physical poles (kinda like a trough of water on a see saw- the water always goes downhill but the direction of down hill constantly changes). This is because city power plants are not batteries but generators that operate by spinning a magnet inside a coil of wires that pull out the electrons in pulses that constantly reverse direction because the poles of the spinning magnet constantly changes direction as it spins.

The purpose of a diode is to turn the a/c to d/c so your d/c home appliance can run on electricty that comes out of the a/c grid.

Dont know exactly how a diode does that, but it does not force the electrons to go 'uphill' to a negatively charged pole. It basically acts like a pressure valve in a water pipe- when the a/c electrons happen to be going the right direction-it lets them in and they become direct current electrons.

There is "conventional flow" which is indicated on the circuit diagrams from positive to negative and actual flow which is the way most of the electrons go.

When Ben Franklin introduced the idea of positive and negative charge no one know anything about electrons. As a result it was thought that the positively charged body had the charge and the negatively charged body lacked the charge. In fact it is the other way around.

ruveyn

I had the impression that holes (pockets where a lack of electrons exist) that flow from the anode of the battery did the actual work in dc circuits as it tried to get to the cathode of the battery in addition to electrons flowing in the opposite direction to fill the outer orbital shell of the anode. Is this concept wrong?

What about a proton conductor where the main charge carrier is the proton, also what about a beam of positrons ? Strictly speaking a beam of electrons or protons from a cyclotron is an electric current.

Iam still confused,

So, in fact the electrons pass from the negative to the positive yes? That is what the film stated though it was a 1945 film.

But I know a diode allows electricity to pass from positive to negative but not back again. which to me implies the electricity is flowing the other direction from what the film states?

I suspect Feralucce gives the answer Iam looking for, and think you are saying the same thing, Ruveyn, nonetheless, I still dont understand exactly what is being said.

Are you saying that in reality, in a physics discussion, electrons flow from negative to positive, but that electronics name the poles wrongly because it makes more sense to say the pressure is on the positive side whereas in reality it is on the negative side?

If so, and to sum up, electricity flows from a positive named red side of a DC battery to the black negative side and will freely pass through a diode in this direction, but in reality they named them wrong and the electricity is really flowing from negative to positive, so it gets confusing when bringing together the two schools of electronics?

To further muddy the waters, the electrical charge moves faster than the electrons.

In alternating current... the electrons don't even move... they jiggle

The electrons flow from negative to positive, but sometimes negative is being called positive.

Please see:

http://www.rare-earth-magnets.com/t-con ... -flow.aspx

ruveyn

In a word: NO!

the WAY TO THINK OF IT- is to think of "negative" (what is normally called "negative"- the "negative" charge -the negative pole on a battery etc )as "positive", and vice versa.

Just think of it that way for a moment- then it all makes more sense.

What is normally called "negative" is really a 'positive" surplus of something-that something being:electrons.

That positive pile of electrons just naturally "fall" throught the wire to where there is a (negative) deficit of electrons - the what-we-are -calling negative pole of the battery ( but which is conventionally called 'positive').


Thats direct current: electrons going downhill from where they are to where they aint-Positive to negative ( except that is normally labeled "negative to positive").

A diode is like a pressure valve in a water pipe. Basically a one way door. If water pushes on the valve one way it pushes the valve open and water gets in. If it water pushes on it the other way it forces the valve shut. Thus the water goes throught the valve only one direction- but cant go back out. If a random pulse of water goes through the pipe and pushes the valve open- the valve lets that bit of water in and doesnt let it back out- even if 'out' is downhill and the way that water 'wants' to go.

Perfect Ruveyn, thank you.
(Now why though does naturalplastic say "no"?)

Well- it got confusing reading what you were confused about so I thought we should just take it from the top and start over.