Burnham Bob
Well-Known Member
if you get what you pay for why do you pay more for an oil filter for a marine diesel from a chandler that's identical to the same unit for a diesel car from an auto spares shop?
Should +ve and -ve wires be the same diameter?
- Thread starter chrisbitz
- Start date
VicS
Well-Known Member
But the electrons are negatively charged and flow the other way, from the negative terminal of the battery through the device returning to the positive terminal. Does that not mean that the black wires should be thicker than the red ones ?
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MM5AHO
Well-Known Member
But the electrons are negatively charged and flow the other way, from the negative terminal of the battery through the device returning to the positive terminal. Does that not mean that the black wires should be thicker than the red ones ?
That's just a convention made up by physicists to cofrusulate everyone.
We mostly switch the wire carrying the fattest electrons, not the wire with the skinny electrons coming back unladen. That would be like putting the hydrant valve not on the supply hose, but on the drain.
I looked out my ticks-book, here's an extract that explains all...
ELECTRICITY
As you probably know, electricity is the thing that happens when two clouds rub together. Lightning is produced, and in no time at all lightning conductors are sent by the Electricity Board to direct it to near-by pylons, enormous electrical lamposts found mainly in the countryside.
Nowadays we think nothing of relaxing in an electric chair while electric ovens use 'microwaves' (tiny, invisible amounts of hot water) to cook our meals. We use electrocution to help us talk properly, while in the bedroom electric blankets fold themselves. But things weren't always this easy.
It was of course Sir Isaac Walton who invented the electric cable, while waiting for the kettle to boil. He decided to suspend an apple from a wire strung bewteen two opposite poles in a magnetic field near his home. Cable or 'telegraph' poles like these are now an everyday sight in Britain.
The invention of electricity, so named after the 'electricity meters' kept underneath the stairs, meant that
previously 'wireless' radios could now be plugged in, giving them pictures. Almost overnight, television had been born. Electricity charges of 240 volts (about 10 pounds per week) are commonplace today, but electricity had been free up until the time of the Norman Conquest. Norman's brother, William the Conqueror, caused an electric storm when he announced that people would have to pay for their electricity. This earned him the nickname 'Electricity Bill', a term which is still in use today.
Most electricity is manufactured in big power stations where it is fed into wires that are wound round large drums put into cans where some special transformation takes place so the new electricity can be pumped through long hollow tubes to another can in your house. Some electricity, however, does not need to go along wires: that used for lightning, for example, and in potable radios. This kind of electricity is not generated in large power stations and pumped round the country, but is lying about loose in the air loose.
Electricity makes a humming noise. This noise may be pitched at different levels for use in doorbells, telephones, computers and electric organs. Electricity has to be grounded. That is to say, it has to be connected to the ground before it can function, except in the case of airplanes and missiles which have separate arrangements. Electricity is made of two ingredients, negative and positive. Each ingredient travels along a wire covered with different coloured plastics. When two wires meet at a socket and go into some appliance or other, the ingredients mix to form the working fluid or essence of electricity. Electricity can be stored in batteries and capacitors. In big batteries the electricity is just shoveled in, while in small batteries it is more carefully packed flat.
Electricity does not leak out of an empty socket. It just sits there waiting for something to enter the socket and mix the ingredients of positive and negative in just the right way. You can find out about this by putting your finger accidentally into an empty socket when the switch is turned on. The demonstration will be most illuminating. The average Fochaberian is content to take all this for granted. He or she will press a switch and the light comes on - and that is all they know about the complex technological miracle they have just unleashed. This has never been enough for me. I have to know how things work; and if I cannot find our from some technical handbook, then I combine such information as I already have with some simple logic. And if that doesn't work, I just make it all up.
Thus it is easy to deduce that the light switch controls a very small clamp or vice that grips the wire very hard, so that the electricity cannot get through. When the switch is turned to the "on" position, the vice is relaxed and the electricity ingredients are permitted to flow to the light bulb itself where a bit of wire, called the filament, is left exposed inside the bulb. Here for the first time, we can actually see the electricity in the form of a spark on the thin filament. We can't see this on ordinary wire because of the plastic covering. This little spark is then magnified many hundreds of times by the curved bulb which is made of magnifying glass. Very special glass is used for light bulbs so that it can diffuse the light from the spark while it is magnifying it.
There are two main types of electricity. The first, which we use every day to light our rooms, comes in bulbs, a special kind of onion grown in the soil, (hence its name 'earth' electricity). 'Live' electricity , which comes from animals, is far more dangerous, as King Canute discovered when a spider burnt his cakes giving him an 'electric shock'. But it was Dr.David Livingstone, with his unusual ability to talk to animals, who first harnessed this form of electricity. His 'Davy' lamp, containing a bright yellow canary, was used to light coal mines, and these 'miner' birds are today a popular household pet.
As recently as 1966, Sir Stanley Mattews was awarded the World Cup for his discovery that the electric atmosphere found inside football stadiums could be used to power enormous 'floodlights' during periods of heavy rainfall. More recently 'damns', (so named by an architect after he'd forgotten to leave a gap for the water while building a bridge), have been used to prevent flooding. In Britain today, there are millions of 'electric fans'; people who prefer electricity to other forms of energy. For further information send a SAE to your nearest Electrical Dealer or write to the Electricity Consumer's Council, a voluntary organisation set up to help people who have consumed large amounts of electric currants etc.
The electricity that is used in transistor radios consists of two kinds; the kind that was packed into small batteries, and the free electricity in the air . The first kind is easiest to explain. When the switch is turned on, the ingredients stored in the battery flow to the transistors where they work something like the filament in the light, only they make it possible to hear the electricity that's free in the air. There isn't enough power in the battery to let us see the electricity in the transistors. There is enough to let us smell electricity in the transistors if the negative and positive electricity ingredients somehow flow backwards through the transistors. This also causes a loss of hearing in the experimenter because the sound of electricity in the air ceases as soon as the smell starts. Never smell electricity this way if you want to hear something from the electricity in the air.
The electricity in the air is universal, and very powerful. I know this is true because I tried listening to it with more that one transistor radio and all the radios I could find sounded the same. Electricity in the air isn't diminished if you listen to it. It's sort of like reading, the print isn't worn off the paper because you read it.
The really fancy electricity in the air is able to make sounds like music or voices in radios or pictures in television sets. And here's where the explanation gets very complicated. All the electricity our there in the air has all those sound and pictures in it all the time. We need the radio or TV set to hear them or see them just like the light bulb lets us see electricity.
One more important thing about electricity is that instead of flowing just straight on a wire so that a light will work, there is twisted electricity. When you connect a motor to the wires, the twisted electricity goes in the motor and unwinds, just like a rubber band in a toy airplane, only the electricity was twisted at the generating station, and it will run a motor forever while the rubber band eventually stops. I'll have to take more time to think out how the straight electricity and the twisted electricity can move on the same wire. Maybe one goes on the wire and the other goes on it, but I'll have to do an experiment to find out. I know that some electricity is along the wire because I tried taking the plastic off and there was electricity when I touched the bare wire. I don't know how to get inside the wire yet, but when I do I'll tell you about that too. Tha might be the topic of my speech next year.
Merry Christmas. Now I know how those lights on the tree work.
halcyon
Well-Known Member
No Regrets
Well-Known Member
Clearly the current flows via the thicker Red wires to the device, gets used up, and whats left goes back via the thin Black wires to get recycled.
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