SRL Archive - Discussions & Debates

I have a question that I've been wanting answered for quite a long time…

I know that electricity flows in currents through objects that conduct electricity.

But, what "tells" the electricity what to do?

For example, a simple fan. The electricity flows from the electrical outlet, through the cord, to some sort of electrical box. How does this electricity tell the rotors to spin?

Another example, a computer's beep noises. On screen, you tell the sound to beep. But, how does the electricity tell the speakers to beep? How does this electricity "know" what to do?

Sorry if this all sounds childish, but I'd really appreciate an answer.

it doesn't "tell" it to beep nor does it "tell" anything, anything. It simply give's it the power to.

The fan is made to spin by little motors, the electricity only give's power to the motors.

Ok, it gives it the power to do it.

How does this power know what to do?

in the same way that water flows down a hill, charge carriers move through a wire.

Ok, so the charge is through the wire. But how does the charge know to make the fan move forwards rather than, say backwards? Or how does it know to do that rather than make the computer beep rather than beep twice?

The electricity it self doesn't do that. For instance, there is a switch on Fans that can reverse the way they spin. That has nothing to do with the electricity.
The computer is only programmed to beep once, the electricity merely give's it the power to do so.

How does the electricity know what to do, though?

Strobe lights, how does the electricity tell it to work?

i know what you mean. same with a few things in life. what tells a cemical to react? what makes a man love a woman… good question.

From: jakeyboy29
i know what you mean. same with a few things in life. what tells a cemical to react? what makes a man love a woman… good question.

Yes, exactly.

People have told me that it occurs and when it occurs, but so far I've no answers of HOW and WHY it occurs.

its basicly like blood flowing through your body in simpler terms ur blood doesnt control you ur brain does

Men and women become attracted to each other because of hormones.

About the electricity (haven't studied this on physics for well over a year…), there is a charge in the power supply (230V plug, power station, battery etc.), and the electricity is able to flow through it. The electrons begin moving, and the output receives the charge, and does what its programmed to do. Switches the prevent the circuit from flowing through control whether it is on or off.

Just in case you didn't know, you can move faster than electronical charge.

Electricity carries a charge, but it also creates a magnetic field. That's why it's often called electromagnetism, or electromagnetics. When the electricity stops flowing, the magnetic field ceases to exist. So, you could imagine a simple motor that senses the magnetic field caused by electrical current and starts moving. If you reverse the direction the electricity flows you also reverse the orientation of the electric field, so the motor would also run in reverse.

From: pur3b100d
its basicly like blood flowing through your body in simpler terms ur blood doesnt control you ur brain does

How does your brain know that it exists and know what to do?

From: pur3b100d
its basicly like blood flowing through your body in simpler terms ur blood doesnt control you ur brain does

Not really at all like that. Blood is a transport system for oxygen/carbon dioxide and nutrients/waste.

Like tara said its has a lot to do with magnetic forces that current carrying wires create. Ill explain you examples.
But if you really want to learn lots about it and go into the actual deeper concepts of it… take grade 12 physics

Speaker:


First off, you know how sound works right? They are waves traveling through the air created by disturbances (vibrations). This is how a speaker makes sound.

See in the diagram above the part labeled diaphragm (AKA the cone). That is what creates the disturbances in the air causing sound waves. They are generally made of some sort of fabric like material.

Now, there is a peace labeled as the "Voice Coil" which is attached to the back of the diaphragm which has two wires coming off of it labeled "Signal input". This is where the electricity comes into place, imagine one of the wires as positive and the other negative. So its not really 2 inputs, think of it as and input and a pseudo output i guess. So the coil itself is what it seems to be, a coil of copper wire. Now when wire is coiled and a current is ran through it, it creates a magnetic field… this brings us to the next object…

The Magnet! Now, what happens when you bring two magnets close to eachother? They either pull or push eachother, right? This is the same concept. The current is ran through the coil creating a magnet and depending which direction the current is flowing it will either create a North or South pole. This will then react this the magnet behind it, so therefore the coil should move either forwards or backwards. And since the coil is attached to the cone, that would move too.

Now back to the sound waves… if the cone moves, what happens? It creates a disturbance in the air, which are also known as sound waves! Now the current changes direction and strengths to cause different vibrational speeds to create different sounds.

This is how a speaker works.

Any questions? :)

I'll explain a motor later if you want.

erm i dont meen to take on the great hobbit but i was just relating blood to electricity as a body cannot work with out blood a ciruit cannot woork without electricity…

But the speed blood moves is incredible compared to the speed electrons move, and the body is collecting vital substances for the brain, which you say is the "power supply", the heart is in fact this "power supply", and all other parts of the body benefit.

A current in a wire (or anything) in a magnetic field produces a force at right angles to both the wire and the current flow on the conductor it's flowing through. So if you had a magnetic field going from north to south, a wire with a current flowing through it from east to west, a force would be produced downwards (if viewing from above, like a compass) on the conductor.

Motors exploit this by looping a conductor through a magnetic field, so it goes through it, out one side, then back into it the other way. So when a current runs through the wire, on one side of it the force will be up, and on the other, down. So a net torque is produced in the wire, which, if put on a rotating axis, will spin. The direction of current has to be reversed every half turn though to maintain the torque in the same direction.

As for electrons and how they know what to do, it's just nature. You're talking about electricity, so electrons flowing through a metal. In metal, the electrons are delocalised, and it's just natures natural tendancy to get to the lowest energy state possible - so a charge on one end will spread through the wire until it's at an equilibrium. If you provide a continual charge, and have something drawing power at the other end, there will be a potential difference and the electrons will flow continually to try to get to the lowest energy state again. I don't like the river analogy (as its due to gravity) or the blood flow, I'd say its more similar to a cold glass of water warming up until it's at room temperature. Same principle, nature going to the lowest energy state to be as stable as possible.

From: Richard
Men and women become attracted to each other because of hormones.

so there are different hormones for gay people? so we could tell if a child is going to be gay from birth?

If it was hormones, then you could make epicly good love pills ;D ?

Eat and fall in love with the next person you see!

Nothx.

Richard meant that hormones make the genders feel attraction to eachother, e.g a man sees a woman on the street, hormones start to do crap.

TViYH, this is a stupid question (no offence). Electricity doesnt tell anything to do anything. It gives power to things. Surely you must have studied this?

A fan turns forwards because the motor spins that way..

From: Torrent of Flame
TViYH, this is a stupid question (no offence). Electricity doesnt tell anything to do anything. It gives power to things. Surely you must have studied this?

A fan turns forwards because the motor spins that way..

It is not a stupid question.
He wondered and he is perfectly welcome to ask questions like this.

Electricity is just a flow of current. It is basically a rotation of positive and negative ions flowing in a circular motion, from positive to negative and then back again. Although in the process of electrical flow, ions are lost therefore new ions from the electrical box (that are almost like waiting in line) jump into the flow of current to replace them.

A simple fan is basically a DC motor. It is a magnetic force that is being charged with electrical ions, causing a reflective force to happen around the metal that is around it pushing it in a circular motion. This is the basic principal of most engines and motors, only inn bigger machines the magnetic force is a ton stronger.

The electricity does not 'tell' what to do, but simply it is a charge of ions that are released to a certain area, such as a light flicker, based on the motion of current flow. There isn't always just one/two path for the electricity to flow, if it was then it would be a single circuit. Many electrical objects are built on parallel circuits so that the a breakage in a point of the circuit does not disturb the rest of the circuits in the power flow.

Hope I helped :P



~NS

From: Hobbit
It is not a stupid question.
He wondered and he is perfectly welcome to ask questions like this.

Fair does, but I didnt mean it in such of a way of mocking TViYH's intelligence. I phrased the statement wrong.