 An electrical charge is an electric property of matter. An object can have a negative, a positive, or not charge.  Like electrical charges repel each other. Opposite electrical charges attract each other.

 Electrical charge can easily been seen by rubbing a balloon against your hair. The balloon is now attracted to your hair. They must have opposite charges.  If you rub two balloons against your hair and put them together they may attract or repel each other. One side of each balloon will have a positive charge and the other negative.  This is an example of static electricity.

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 Atoms are made of protons (positive charge), neutrons (no charge), and electrons (negative charge).  When electrons and protons in an object are equal they do not have a charge. If they are not equal they atom may have a positive or negative charge.  Protons and Neutrons are in the nucleus of an atom in a fixed position. However, Electrons are on the outermost part of an atom and can easily move from one atom to another.

 When different materials are rubbed together, electrons can be transferred from one material to the other.  Objects are charged by friction during static electricity.  Electrons are transferred from one object to another by friction.  One material gains electrons and the other loses electrons. So one object is positively charged and the other is negatively charged.

 When you bring a charged object near a neutral object electrons are forced from one side of the object to the other.

 Some things allow electrical charges to flow easily. These objects are known as conductors. Metals are typically good conductors. That is why wires often contain copper.  Insulators do not allow electrical charges to flow easily. Wires are wrapped in insulators so you do not get shocked. Good insulators include cardboard, plastic, glass, and silk.

 Electricity at is basic level is the flow of electrons! (electrons can be pushed out of their atomic orbits and forced to move from one atom to another which is called electricity.  A current is the rate at which the electrons flow through something like a wire.  Voltage is the pressure that pushes electrons through a circuit.  Intros/DCI/Flash/WaterAnalogy.html. Intros/DCI/Flash/WaterAnalogy.html

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 Voltage = Current x Resistance or V = I R  Voltage is the pressure that is pushing electrons. An analogy can be drawn between water pressure and voltage. If you hung a water tank 1 cm above the and 100 cm above the ground, then allowed the water to flow through the pipe which would have more pressure?  The units of Voltage is volts.

 Current is the flow of electrons. (measured in amps)  Again, an analogy can be drawn between current and the flow of water.  Current is measured by counting the number of electrons flowing past a fixed point.  Resistance is the property that slows the flow of electrons and is measured in Ohms. An analogy can be drawn between water and a pipe and resistance. If you were to put something in the pipe to slow water flow you would be creating resistance.

 Magnets produce magnetic poles  Magnetic poles are opposite ends of a magnet.  Magnets always have a north and a south pole.  The north pole is always attracted to the south pole. Just like electricity, opposites attract.  Like poles repel.

 A permanent magnet keeps its magnetic field. You can turn pieces of iron into a permanent magnet by places it in a strong magnetic field.  Other times pieces of metal can become a temporary magnet. When the piece of iron is in the magnetic field it is magnetized. When it is removed from the magnetic field it is no longer magnetized

 Magnets exert magnetic force on each other.  You can feel the force when you place to like magnetic poles next to each other.  A magnetic field is a region where a magnetic force can be detected.

 The movement of electrons in atoms creates magnetic fields.  Some materials such as copper are not magnetic because the magnetic fields of individual atoms council each other out.  Other material s like iron, nickel, and cobalt are magnetic because the individual magnetic fields created by atoms do not cancel each other out.

 A compass has a small needle as its pointer.  The compass points towards the north and south pole according to the earth’s magnetic field.  The north pole of the magnet points towards the south pole of the earth’s magnetic field and vice versa.  Magnetic north is actually at the south pole and magnetic south is at the north pole.

When a wire carries a current it produces a magnetic field. This is called electromagnetism.

 The direction of the magnetic field and current can be determined by the right hand rule.  If you hold a wire in your right hand and point your thumb in the direction of the positive current, the direction that your fingers curl is the direction of the magnetic field.

 Electric motors use electromagnetism. These can be found in washing machines, toys, dryers, and many other household items.

 Moving a magnet into an out of a coil of wire causes charges in the wire to move. This is known as electromagnetic induction.

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