Conventional currentYouTube↗  IA↗(long shot)
Education  243.9K views 878 likes 77 dislikes   17 Jun 2016
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when we start to study electricity we
- [Voiceover] When we start to study electricity,
need to get an idea of what is current
we need to get an idea of what is Current
and what is voltage and in to earlier
and what is Voltage and
videos I talked about the idea of
in two earlier videos,
current and voltage current and voltage and what they meant and when we talked
I talked about the idea of current and voltage, current and voltage and, and what they meant.
about current it's easiest to describe
And when we talked about current,
current when we talk about wires let's
it's easiest to describe current when we talk about wires.
say we have a copper wire we talked
Let's say we have a copper wire.
about a copper wire and inside it was
We talked about a copper wire and inside it was,
there is electrons in it and they have a
there was electrons in it,
negative charge we know they have a
and they have a negative charge, we know
negative charge and if we put a voltage
they have a negative charge,
on them those electrons would move in some direction like that so if I put a
and if we put a voltage on them, those electrons would move in some direction like that.
plus voltage over here and a minus
So if I put a plus voltage over here
voltage over here the electrons are
and a minus voltage over here,
repelled by the minus voltage and
the electrons are repelled
they're attracted to the positive
by the minus voltage and they're attracted
voltage that is called an electron
to the positive voltage.
current you
That is called an Electron Current.
so talking about current in terms of
So talking about current
what's actually happening in inside a
in terms of what's actually happening inside a wire
wire make some sense it's easier to
makes some sense, it's easier to understand current and
understand current and that these
that these electrons are moving around.
electrons are moving around and whenever
And whenever we talk about this,
we talk about this we'll talk about it
we'll talk about it specifically
specifically that there's an electron current going on here now at the same
that there's an electron current going on here.
time what I said in that video and I'll
Now at the same time, what I said in that video,
say again is the convention for
and I'll say again,
describing current is this this is
is the convention for describing current is this.
called the conventional current direction
This is called the Conventional Current Direction.
the convention we've had for hundreds of
The convention we've had for hundreds of years
years is that current is the direction
is that current is the direction
that a positive charge would move if
that a positive charge would move
there was a positive charge there so
if there was a positive charge there.
whenever we talk about current from now
So, whenever we talk about current from now on,
on it'll always be conventional current
it'll always be conventional current,
and in fact we don't even need to
and in fact, we don't even need to mention
mention conventional anymore it's just current current is the
conventional any more, it's just current.
direction that positive charges would
Current is the direction that positive charges would move.
move if we ever talk about electron
If we ever talk about electron current then we'll use
current then we'll use the word electron current now as a reminder when we talked about voltage this was built up by
the word, electron current. Now, as a reminder, when we talked about voltage, uh, this was built up by analogy
analogy the analogy was to electrons rolling down a mountaintop so here's our
and the analogy was to electrons rolling down a mountaintop,
mountain to remember this and I built a
so here's our mountain, remember this?
battery or another voltage source like this and we said that what a battery
And I built a battery or another voltage source like this, and we said, that what a battery does is it
does is it pumps out energetic electrons and they go down a hill roll downhill
pumps out energetic electrons, and they go down a hill.
and go back into the back into the
Roll downhill and go back into the,
positive terminal of the battery and
back into the positive terminal of the battery.
when we design circuits what we do is we
And when we design circuits, what we do, is we,
we put stuff in the way of this electron
we put stuff in the way of this electron on
on his path and this is where we build our circuits so the the electron current
its path, and this is where we build our circuits. So the, the electron current is
is going in this direction here down the
going in this direction here down the hill.
hill the conventional current direction
The conventional current direction or
or the current direction is this way so
the current direction is this way.
now I'm going to redraw my circuit in my
So now, I'm gonna redraw my circuit and my battery.
battery I'm going to flip the battery
I'm gonna flip the battery around it
around it until the positive terminal is on the top and I'll put my circuit over
until the positive terminal is on the top, and I'll put my circuit
on the side over here like this there's
over on the side over here like this.
my circuit that I just built let's
There's my circuit that I just built.
connect those circuits up like that this
Let's connect those circuits up like that.
is the plus side of the battery this is
This is the plus side of the battery,
the minus side the plus side goes with
this is the minus side.
the long bar and the minus side goes
The plus side goes with the long bar
with the short bar there and the current
and the minus side goes with the short bar there.
direction here the conventional current
And the current direction here,
direction or just plain current
the conventional current direction,
direction is in that direction out of
or just plain current direction,
the positive and back into the negative
is in that direction. Out of the positive and back into the negative.
from now on this is what we mean by
From now on, this is what we mean by current.
current and we know that the electrons
And we know that the electrons are in here.
are in here they're heading around this way like that but that's okay this is
They're heading around this way, like that, but that's okay.
the this is the nomenclature for
This is the, this is the nomenclature
or conventional current or just plain current
for conventional current or just plain current.
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