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Electricity is a flow of charged particles. These particles originate in the atom. If you have ever

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studied the atom you will know that an atom has a compact center called the nucleus. The nucleus

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contains two types of particles, protons which have a positive electric charge and neutrons

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which have no electric charge. Small charged particles called electrons exist outside of

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of the nucleus. Electrons have a negative charge and they are attracted to the positively

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charged protons. The electrons move in high speed orbits around the nucleus, held close

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to the nucleus by the strong force of attraction from the protons. You can witness this force

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by rubbing a balloon on fabric, creating an imbalance of electrons and protons. Small

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All pieces of paper will stand up and jump to the negatively charged balloon.

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Scientists call this static electricity because the charge doesn't move.

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It stays on the balloon.

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Two negatively charged balloons repel one another.

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The light charges on each balloon repel.

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This force can cause electrons to move from one place to another.

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When electrons flow between two points, we call this electricity.

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One of the most dramatic effects of electricity is a lightning strike.

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Electrically charged clouds release their charge in an explosive flash.

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A powerful demonstration of electricity.

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To use electricity, we need to find a way to safely contain and control this flow of charged particles.

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That is what a battery cell does.

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is a chemical device capable of converting stored chemical energy into electrical energy.

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As you know, batteries have two terminals or ends labeled plus and minus.

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This reflects the negative and positive charges on electrons and protons.

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The chemistry of a battery creates a force that moves electrons out of the metal plate on the negative end

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and attracts them to the metal bump on the positive end.

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Electrons will start to move from minus to plus if the right kind of material is connected to the battery.

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Materials that allow electricity to travel through them are called conductors.

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Most metals are good conductors of electricity.

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Copper is the most common metal used in wires.

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In this animation, a conductor is connected to each terminal of a battery.

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Electrons start to move, traveling from the negative terminal towards the positive terminal.

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This is electricity.

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The electrons actually move from atom to atom as they travel through the conductor.

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This is a safety warning.

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Never connect a short metal wire between the terminals of a battery.

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This is a short circuit.

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The wire will get hot, you might burn yourself, and the battery will quickly lose its energy.

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Have you noticed the letter V on the side of a battery?

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This represents volts.

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Volts, or voltage, is a measure of the force moving the electrons.

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A AA battery is usually 1.5 volts.

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This is a low voltage, and that is why it is safe to handle a AA battery.

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Higher voltages are dangerous.

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Never experiment with anything that plugs into a wall outlet.

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Wall outlet voltages range from 120 volts to 240 volts.

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Extremely dangerous.

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Here is an example of a low voltage battery being used to create some light.

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Connecting a light bulb to this battery, we have created a circuit, a path for electrons to travel on.

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Our light bulb does two things.

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It introduces some resistance into the circuit, reducing the flow of electrons so that the copper wires won't get hot.

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and it converts electrical energy into light energy.

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Our circuit also demonstrates a switch,

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a device for turning the electricity off and on.

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The switch does this by creating an opening in the circuit.

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This is an actual circuit similar to the one in the animation.

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The wires I am using have metal alligator clips connected to their ends,

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making it easy to connect.

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The metal in these wires is covered in plastic.

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plastic is an electrical insulator the current from our low voltage battery will not flow

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through the plastic but easily travels in the copper wire under the plastic connecting and

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disconnecting the wire creates a simple switch turning the light off and on a wall switch does

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the same thing the plastic lever and cover plate protect you from the high voltage used in this

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circuit. It is possible to construct circuits with two or more bulbs. Here is

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one example. The two bulbs in this circuit are connected in parallel. If we

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follow two electrons traveling through this circuit, we see there are two

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possible paths. One electron leaves the negative terminal of the battery and

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travels through the upper bulb, the other through the lower bulb. They both end at

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positive terminal of the battery. Parallel circuits always provide more

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than one path for the electricity to travel on. If you are in a room with a

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row of ceiling lights, these lights will be connected in parallel. One advantage

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of connecting lights in parallel is that if one light is removed or fails, the

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other lights will not be affected. Removing one light from this circuit

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does not affect the other light. It remains connected to the battery. This is a parallel

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circuit. Notice when I disconnect one bulb, the other one stays on. It is possible to

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build parallel circuits with many branches. This circuit also has two bulbs, but notice

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there is only one path. This is a series circuit. All electrons travel from minus to plus following

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to plus following the same path. If one of these lights is removed or fails the

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circuit is broken and the other light will go out. Lighting systems are rarely

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wired in series. This is a series circuit. Notice when I disconnect one bulb the

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other one goes out. Switches are wired in series with the loads they control. In

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In this example, our lights are the loads, and this circuit contains a series and parallel component.

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The switch is in series with the parallel branches.

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This is how one switch controls many lights in a room.

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Series and parallel circuits can be found in all electrical and electronic devices.

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The wiring in your home is a combination of series and parallel circuits.

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This motherboard of a computer consists of a maze of series and parallel circuits connected to control the electronic components that allow the computer to function.

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If you are interested in learning more about electricity and electronics, science and hobby supply retailers often have battery operated electronics experimenters kits designed to let you safely learn about electricity.

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More science and technology related videos can be found at our website, hylerode.com. Follow the videos link.