Matter is made from atoms that are small particles. Atoms are made from protons, neutrons, and electrons that are even smaller. Charge is a physical property so an object can have a negative, positive effects, or no charge at all. Charged objects are pulled or pushed by other charged objects. The Law of Electric Charges says that charges can repel or attract.
Atoms have a equal amount of protons and electrons, so the positive and negative charges cancel each other out. The atoms have no charge. The only way an object made of atoms can be charged is if it becomes a positively charged object and loses its electrons, or if it becomes a negatively charged object when it gains electrons.
Electric Charge, continued The Force Between Protons and Electrons Because protons and electrons have opposite charges, they are attracted to each other. The Electric Force and the Electric Field The force between charged objects is an electric force. An electric field is the region around a charged object in which an electric force is exerted on another charged object.
When an object is charged by friction it’s when electrons are wiped from one object to another. Example: if you use a cloth to rub a plastic ruler, electrons move from the cloth to the ruler. So the ruler gets electrons and becomes negatively charged, as for the cloth it becomes positively charged because it loses electrons.
If something is charged by conduction then electrons have moved from one object to another by direct contact. For example: if you touch an uncharged piece of metal with a positively charged glass rod. The electrons from the metal will move to the glass rod making a negatively charged object. As for the metal it loses electrons and becomes a positively charged object.
If an object is charged by induction it’s when charges in an uncharged metal object are rearranged without direct contact with a charged object. For example: if you hold a metal object near a positively charged object, the electrons in the metal are attracted to and move toward the positively charged object. This causes or induces an area of negative charge on the surface of the metal.
Charge It! Friction Charging by friction happens when electrons are “wiped” from one object onto another. Conduction Charging by conduction happens when electrons move from one object to another by direct contact. Induction Charging by induction happens when charges in an uncharged metal object are rearranged without direct contact with a charged object.
Charge It!, continued Conservation of Charge When you charge something by any method, no charges are created or destroyed. The numbers of electrons and protons stay the same. Detecting Charge You can use a device called an electroscope to see if something is charged.
A electric conductor is a material in which charges can move easily. Usually most metals are good conductors. This is because most of the electrons are free to move. Also copper, aluminum, and mercury are good conductors. For example: a lamp cord has metal wire and metal prongs.
A electrical insulator is a material in which charges cannot move easily. Insulators don’t conduct charges as well as conductors because their electrons don’t move as easily and freely. This is because the electrons are tightly held in the atom of the insulator. Plastic, rubber, glass, wood, and air are also good insulators. For example: the insulating material in a lamp cord stops charges from leaving the wire and protects you from electric shock
Static Electricity Static electricity is the electric charge at rest on an object. Electric Discharge The loss of static electricity as charges move off an object is called electric discharge.
Static electricity is the electric charge at rest on an object. If something is static that means that it’s not moving, so the charges of static electricity don’t move from the object they’re in. Which makes the object keep its charge. For Example: your clothes are charged by friction as they rub against each other inside a dryer. As the clothes tumble, negative charges are lost by some clothes and build up on other clothes. When the dryer stops, the transfer of charges also stops. And because clothing is an insulator, the built-up electric charges stay on each piece of clothing. The result of this buildup of charges is static cling.
Electric discharge is the release of electricity stored in a source. This can happen slowly, for example when clothes are stuck together by static electricity they will separate on it’s own time. Then over time the electrical charges move to water molecules in the air. Though sometimes electric discharge does happen quickly. It could happen through a flash of light, a shock, or a crackling noise. For example if you’re wearing rubber soled shoes and walk on carpet the negative charges build up in your body.