Electricity and Magnetism PDF

ELECTRICITY & MAGNETISM ELECTRICITY & MAGNETISM ELECTRICITY CAN PRODUCE MAGNETISM MAGNETISM CAN CREATE ELECTRICITY When charges from one piece of matter interact with those from another piece of matter, they produce...

ELECTRICITY & MAGNETISM ELECTRICITY & MAGNETISM ELECTRICITY CAN PRODUCE MAGNETISM MAGNETISM CAN CREATE ELECTRICITY When charges from one piece of matter interact with those from another piece of matter, they produce both electric and magnetic forces. WHAT IS ELECTRICITY? ELECTRICITY IS THE INTERACTION OF ELECTRIC CHARGES. Electric charges are a fundamental property of protons and electrons, which make up every atom. Positive and negative charges are the two types of electric charges. Protons possess a positive charge, whereas electrons carry a negative charge. LAW OF LIKE CHARGES REPEL ELECTRIC CHARGES THE ELECTRIC FORCE IS THE ATTRACTION OR REPULSION BETWEEN CHARGED OBJECTS. UNLIKE CHARGES ATTRACT COULOMB'S LAW The size of charges and the distance between them are both key factors in determining the strength of the electric force between charged objects.  STATIC ELECTRICITY THE BUILD UP OF ELECTRIC CHARGES ON AN OBJECT When you rub a balloon against your hair, electrons from the atoms that make up your hair transfer to the balloon, which makes your hair positively charged due to electron loss. The balloon becomes negatively charged due to electron gain. When you hold the balloon several centimeters from your head, your hair stands up due to the attraction between the two opposite charges. The charges that build up on an object do eventually move off the object. This sudden and brief flow of electrons is called: ELECTRIC DISCHARGE Have you ever received a shock when you touch a metal doorknob after shuffling your feet on the carpet? That is an example of electric discharge on a small scale. Can you think of an example of electric discharge on a larger scale? Here's a hint (insert clip of lightning)  ELECTRIC CURRENT CURRENT ELECTRICITY IS A CONTINUOUS FLOW OF ELECTRIC CHARGE Current is defined as the quantity of charge that flows past a given point per unit of time. The standard unit of measurement for current is the ampere (A). DIRECT CURRENT (DC) A type of electric current where the charges flow in one direction only. Batteries are an example of a direct current source. ALTERNATING CURRENT (AC) A type of electric current that flows in one direction, then the reverse direction, repeatedly. The electric current supplied by power companies to homes is an example of AC. CONDUCTORS Examples of Insulators: Rubber Air & INSULATORS Glass Plastic Wood Paper Conductors are materials that allow an electric current to flow through them easily, while insulators are materials that resist the flow of electric current. Examples of Conductors: Metals such as copper, aluminum, silver, and gold Water (when it contains dissolved salts or other charged particles) Graphite (found in pencils) Human body (can conduct small amounts of electric current) PARTS OF A CIRCUIT ELECTRIC Energy source: An electric field created by a battery's positively and negatively charged terminals attracts and repels charges, providing the push to keep them moving CIRCUITS through a closed circuit. LOAD Load: A component in a circuit that consumes electrical energy to perform a function, such as generating light or ENERGY SOURCE motion, and resists the flow of electric current, causing a voltage drop. Wires: A low-resistance conductor that carries current in a circuit, connecting components. Material and thickness are selected based on distance, current, and voltage for WIRES efficient and safe operation. Switch: A switch controls a circuit by connecting or disconnecting two metal pieces. When the pieces touch, the circuit closes; when they separate, the circuit opens. SWITCH WHAT IS MAGNETISM? A force that can attract or repel certain materials, such as iron, and is caused by the LIKE CHARGES REPEL movement of electric charges within certain objects, like magnets or electric currents. N S S N S N N S UNLIKE CHARGES ATTRACT Magnets attract iron and have two poles, a negative and a positive pole, where the magnetic force is S N S N strongest. All magnets share these properties.  MAGNETIC FIELD THE REGION AROUND A MAGNET THAT IS AFFECTED BY MAGNETIC FORCES. N S WHAT DO YOU THINK IT MIGHT LOOK LIKE?  MAGNETIC FIELD THE REGION AROUND A MAGNET THAT IS AFFECTED BY MAGNETIC FORCES. N S DID YOU KNOW? Earth's magnetic field is what makes compasses work? The needle of a compass is a tiny magnet that aligns with the Earth's magnetic field, pointing north-south. This is possible because the Earth itself acts as a giant magnet thanks to its magnetic core, which generates a magnetic field that extends far into space. This field is what protects us from the solar wind and other harmful particles that constantly bombard our planet. Without it, life on Earth as we know it would not be possible. ELECTROMAGNETIC INDUCTION Physicist Hans Christian Oersted was the first to discover that electric current produces a magnetic field around a wire. To produce a strong magnetic field, wrap coils of wire around an iron rod. Current passing through the coils of wire magnetizes the rod, producing a powerful magnet, called an electromagnet. The more loops in the coil the stronger the magnetic field. Electromagnets are used in electric motors, loudspeakers, television sets, doorbells, trains, and many other devices. ELECTROMAGNETIC INDUCTION Michael Faraday's Electromagnetic Induction The process of creating an electric current by moving a conductor through a magnetic field or by varying the magnetic field around it. The majority of the electricity supplied to homes is generated using electromagnetic induction. ELECTROMAGNETIC INDUCTION Heinrich Lenz’s Law Lenz's law states that the direction of the electric current induced in a conductor by a changing magnetic field is such that the magnetic field created by the induced current opposes changes in the initial magnetic field. ELECTRIC GENERATOR MACHINES THAT CONVERTS MECHANICAL ENERGY INTO ELECTRICITY Power Plant Diesel Generators Diesel generators are very useful machines that produce electricity by burning diesel fuel. These machines use a combination of an electric generator and a diesel engine to generate electricity. Steam Turbine Generators A steam turbine is a machine that extracts thermal energy from pressurized steam and uses it to do mechanical work on spinning an electric generator. Coal Fired Steam Turbine Generator System Hydroelectric Generators Hydroelectric power, electricity produced from generators driven by turbines that convert the potential energy of falling or fast-flowing water into mechanical energy. Hydroelectric Power Generator System