Tax the wealthy. Problem solved.

A Question from my 5 year old

Driving home from the zoo yesterday, passing the CNE wind turbine, my daughter went silent from her normal continuous torrent of observations and questions, and then asked

"Daddy, how does electricity work?"

I was stumped on how to explain this. Coming home I pulled up some websites and she built herself some atoms, but overall I just couldn't find any good interactive material on electricity.

How would you answer that question?
Permalink df 
April 6th, 2008 7:41pm
I spend a lot of fucking time on the internet.  My kid has been asking questions like that since she was 4, and we average about 15 a day.  She's slowed down some as I've gotten tired of looking things up, which makes me feel like a terrible dad.  :P
Permalink Send private email muppet 
April 6th, 2008 7:48pm
As to specific resources for electricity, no idea.
Permalink Send private email muppet 
April 6th, 2008 7:48pm
I remember a grade 7 textbook that had a gremlin inside a battery who would lift the electrons up and then they'd flow down the pipes.  I think i'd go with some sort of water analogy.
Permalink Ward on a Treo 700p 
April 6th, 2008 8:00pm
One end of a power source has a lot of electrons (negative end, if you were curious).  The other end has a shortage.  The electrons will do their best to get from the end with a lot of electrons to the end with the shortage.  They'll take the easiest route there, which is almost always through a wire.

That's the most simplistic view, and is for the most part true for direct current, such as you get from a battery, or inside of any electronic device.

Alternating current, which is used for power transmission, works a little differently.  The electron surplus/deficit switches on a regular basis, causing the electrons to change the direction of flow.  The beauty is that it moves as a wave, rather than just brute force electron pushing, so that energy losses are much less.
Permalink Send private email Clay Dowling 
April 6th, 2008 8:06pm
Tubes? Like the internet.
Permalink bob 
April 6th, 2008 8:15pm
I think I'd skip AC for a couple years....  if you can get the idea of electrons as little balls across, then you can do heat and light as side effects of the balls bouncing around tight corners e.g. in a filament.  once incandescants are gone, that will be much harder since CFs don't work the same way.
Permalink Ward on a Treo 700p 
April 6th, 2008 8:21pm
Electricity is the movement of electrons.

That should cue a whole slew of other questions, but it's essentially true.
Permalink Colm 
April 6th, 2008 8:25pm
I'm looking forward to the incessant questioning stage in my nephews. I can teach them all sorts of stuff like this. It'll be fun :)
Permalink Colm 
April 6th, 2008 8:26pm
>> Electricity is the movement of electrons.

well that's a big help, thanks, I bet he never knew that.
Permalink Ward on a Treo 700p 
April 6th, 2008 8:33pm
He was looking for a concise way to explain it, not asking what it was himself you numbskull.
Permalink Colm 
April 6th, 2008 8:37pm
The balls in a tube analogy was the one I was about to offer up (that the turbine's work forces a ball into a tube, pushing one out on the other end, and you can make that ball popping out on the other end do work for you. Conductors like metal are the tubes), as was the water analogy, but I have a serious dread about placing foundational information like that into her mind, and then it pollutes her understanding of the topic, well, forever.

And of course my own knowledge of electricity isn't all that perfect. For instance the whole thing about electrons only moving about 4 meters per second.
Permalink df 
April 6th, 2008 8:42pm
The topic is frankly a little complex, so it isn't shocking that you are having trouble coming up with answers.  It doesn't have exact physical analogs.  But the electrons are actually moving.
Permalink Send private email Clay Dowling 
April 6th, 2008 9:05pm
>For instance the whole thing about electrons only moving
>about 4 meters per second.

Electrons move about 1/2 millimeter per second.
Permalink Colm 
April 6th, 2008 9:11pm
It's just god power lighting the world.
Permalink Creationist Science Book 
April 6th, 2008 9:38pm
See, this is what happens when you have intelligent kids.

:-)
Permalink Treppenwitz 
April 6th, 2008 9:38pm
http://home.att.net/~numericana/answer/physics.htm#bohr

For small objects like electrons, quantum mechanics states that the very notion of trajectory breaks down.  You can\'t measure both the momentum and the position of a particle:  The product of the uncertainties in the measurements of such conjugate quantities cannot be less than the so-called Heisenberg limit.  Thus, the electron does not have a precise speed in the classical sense.


.......2190 km/s.............
Permalink so many stupid people on cot 
April 6th, 2008 9:48pm
When electric current in a material is proportional to the voltage across it, the material is said to be "ohmic", or to obey Ohm's law. A microscopic view suggests that this proportionality comes from the fact that an applied electric field superimposes a small drift velocity on the free electrons in a metal.

For ordinary currents, this drift velocity is on the order of millimeters per second.

http://hyperphysics.phy-astr.gsu.edu/hbase/electric/ohmmic.html
Permalink Colm 
April 6th, 2008 10:14pm
>so many stupid people on cot

+1
Permalink Colm 
April 6th, 2008 10:14pm
Best analogy -- water in a pipe.

Water in a water tower is like charge in a battery.  Flowing water in a water pipe is like flowing charge (current) in a wire.

A constriction in a pipe is like resistance in a wire.

V = IR, or Voltage = Current * Resistance (Ohm's Law).

So, Current (I) flows in a circuit, based on how much Voltage (pressure) you put across the circuit, and how much resistance (diameter of pipe) is in that circuit.

And when the water pours out onto a water wheel, water pressure is converted into work.  Just as current flowing through a space heater is converted into heat.
Permalink SaveTheHubble 
April 6th, 2008 10:21pm
Colm

You stupid, dishonest, piece of crap.

The full sentence you quote above reads

"For ordinary currents, this drift velocity is on the order of millimeters per second in contrast to the speeds of the electrons themselves which are on the order of a million meters per second."

It now becomes clear that when you said

> Electrons move about 1/2 millimeter per second.

you were wrong.

I guess you confused the average speed of the electrons in the current with the speed of an individual electron. Drift velocity refers to the current itself, not the individual electrons. Any one could make that mistake, cutting the sentence short to hide the truth, only a lying sack of shit would pull that.
Permalink fuck you 
April 6th, 2008 10:42pm
there's a wee bit of resistance in presenting Ohm's Law to a 5-year old. they call it multiplication.

to present what a child sees -- the practical, everyday use of it in our society, the water analogy comes close. it comes in pipes. you can store it in containers. it's a resource. it's a utility. but these are not words understood by a 5-year old either. make it physical. it has to be physical -- a 5-year old's world is very physical not too abstract, she really only acquired the theory of mind in the last 12 months. the explanation has to be composed of the objects used everyday.

except kids don't think of water as powerful. it doesn't do work in their minds, it gets them wet. water in a water wheel has power. but it's gravity's power, not water's. and 5-year olds don't interact with water wheels on a daily basis.

what does do work on its own? fire. electricity is kind of like fire-water (don't touch!). it flows. it can be put into a battery. it gets used up.

but society/technology has standardized it. made in interface for users and producers. like Legos (or some other composable toy). it's a plug and play world, my dear.

now. explain SOA to your boss's boss.
Permalink heartsheep 
April 6th, 2008 10:49pm
I wish my political views wound people on CoT up half as much as simple facts I quoted from a physics textbook.
Permalink Colm 
April 6th, 2008 10:53pm
>I guess you confused the average speed of the electrons in
>the current with the speed of an individual electron.

You should've picked up on that from the context. We're not talking about atoms, we're talking about a current of electrons.

Anybody with a half decent knowledge of physics after seeing what I said would have instantly realized that I was talking about electron movement in a current, even if they hadn't picked up on that from the context.

The fact you called me a liar merely highlights the fact that you didn't realize from the context, you don't have a half decent knowledge of physics and you're kind of a twat.
Permalink Colm 
April 7th, 2008 2:03am
Back on the topic of the OP, I wouldn't try to explain how electricity works in terms of physics, I would explain how electricity works in terms of what it does.

For instance I would get batteries and bulbs and wires and show how electricity works in a practical sense. You can find by experiment that it is "stuff" that flows down metal wires and makes things happen, and you could compare it to the circulating water in a garden fountain.

When I was 10 I couldn't get much beyond that, so I think there is a limit to how much of the underlying science you can explain to a 5 year old.
Permalink Send private email bon vivant 
April 7th, 2008 3:31am
The "Hello World" way of explaining it is with two magnets.  I forget if one side has one polarity, and the other side the other polarity, so that they can stick to each other or repel. 

Now tell him that same force can be used to create friction across a light-bulb, etc.

Of course their is also chemical differences, like with a batter.  EMF - electro-magnetic force.  Voltage give how much force is pushing that charge, and Current gives how much charge is being pushed.
Permalink Send private email LORB 
April 7th, 2008 6:26am
battery
Permalink Send private email LORB 
April 7th, 2008 6:27am
Power = Voltage x Current.

I think you just answer best as you know how.

I have an A.S in Electronics and 2 yrs. work experience in it, that's basically how I know.  hehe.

http://en.wikipedia.org/wiki/Magnet

Anyway, If you cut a magnetic field 90 degrees along a conductor, you have your running electricity.

Too funny, a link for kids:
http://www.powerhousekids.com/stellent2/groups/public/documents/pub/phk_eb_ae_001467.hcsp
Permalink Send private email LORB 
April 7th, 2008 6:49am
You have to either move the conductor through the magnetic field or spin the magnet.  That's why the choose to rotate the magnet.
Permalink Send private email LORB 
April 7th, 2008 6:56am
Hmm, I'm looking at an example from my textbook.  They actually rotate the armature (conductor) in-between two magnetic poles of the same magnet.  It's actually a DC charged electromagnet, by a battery (so, chemical).  Stationary brushes pick the electricity off from the rotating rod (conductor).
Permalink Send private email LORB 
April 7th, 2008 7:19am
After this, EMPHASIS ADDED:

>For instance the whole thing about ELECTRONS ONLY moving
>about 4 meters per second.

Colm>> ELECTRONS move about 1/2 millimeter per second.

and now you want to pretend you were talking about the current?  Get to fuck.
Permalink Admit you are wrong, idiot. 
April 7th, 2008 7:57pm
And electric signals move in wire at about the speed of light.  As Dr. Grace Hopper would demonstrate at her lectures, a signal travels about a foot per nanosecond.
Permalink SaveTheHubble 
April 7th, 2008 8:30pm
Note, that doesn't mean electrons move that fast, or 'holes' move that fast, just that signals propagate that fast.
Permalink SaveTheHubble 
April 8th, 2008 9:23am

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