ELECTRICITY AND MAGNETISM Electricity is one of the most useful of all forms of energy. Electricity can easily be converted to heat, light, mechanical or sound energy.
Electricity can be carried long distances through wires and cables. It is clean and safe if we use it in the right way. Electricity is closely linked with magnetism. When electricity moves, magnetism is created. When magnets move, electricity is created.
Together, electricity and magnetism form one of the forces that holds the universe together: electromagnetism.
TYPES OF ELECTRICITY There are two types of electrical charge: Positive and negative. Objects with opposite charges attract each other and objects with the same charges repel each other. There are two types of electricity: Current Electricity and Static Electricity Current Electricity: Current is the rate of flow of electrons. It is produced by moving electrons and it is measured in amperes.
Static Electricity: Static electricity is when electrical charges build up on the surface of a material.
ELECTRICAL CURRENT AND ELECTRIC CIRCUITS Electrical current is the flow of electrical charges. It transmits energy called electricity. Electrical current flows differently, depending on the type of material through with it flows. Conductors: Electrical current flows easily through conductors. Most metals are conductors.
Insulators: Electrical current does not flow easily trough insulators, such as air, glass, plastic, wood and rubber. Electric circuit A circuit is a path along which an electric current can flow. Each part of the circuit must be connected to the next, and each must be able to conduct electricity. There are four basic components of an electric circuit: - A generator, which is the source of electricity such as an electrical plant or a battery. - An electrical component, such as a light bulb or a motor - Conducting wires - A Switch to control the flow or electrical current. The ON position closes the circuit and allows the flow of electrical current. A switch in the OFF position opens the circuit and breaks the flow of electrical current.
MAGNETS AND MAGNETISM A magnet is an object which can attract objects made of iron or mixtures of iron, such as steel. This attraction is called magnetism. Magnets create magnetic fields. They are the space around a magnet where materials, such as iron filings, are affected by magnetic forces.
Magnets have two poles: north and south. When the opposite poles of two magnets are placed together, the magnets attract each other. If the same poles are placed together, the magnets repel each other.
An electromagnet is a conducting wire wrapped around a piece of iron, called a coil, which acts as a magnet when electrical current flows through it.