Electricity and Magnetism topic in science.pptx

just electricity

1. ELECTRICITY & MAGNETISM

2. Learning Targets Describe the different types of charging processes Explain the importance of earthing and grounding

3. Introduction AGENDA 01 03 04 02 05 06 07 08 09 10 What is Electricity? Law of Electric Charges Static Electricity Electric Currents Conductors & Insulators Electric Circuits What is Magnetism? Magnetic Fields Electro-magnets

4. MAGNETISM CAN CREATE ELECTRICITY ELECTRICITY & MAGNETISM ELECTRICITY CAN PRODUCE MAGNETISM When charges from one piece of matter interact with those from another piece of matter, they produce both electric and magnetic forces.

5. ELECTRICITY IS THE INTERACTION OF ELECTRIC CHARGES. WHAT IS ELECTRICITY? 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.

6. LAW OF ELECTRIC CHARGES LIKE CHARGES REPEL UNLIKE CHARGES ATTRACT THE ELECTRIC FORCE IS THE ATTRACTION OR REPULSION BETWEEN CHARGED OBJECTS. The size of charges and the distance between them are both key factors in determining the strength of the electric force between charged objects. COULOMB'S LAW

7. 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.

8. 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) The charges that build up on an object do eventually move off the object. This sudden and brief flow of electrons is called:

9. 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) ALTERNATING CURRENT (AC) A type of electric current where the charges flow in one direction only. Batteries are an example of a direct current source. 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.

10. CONDUCTORS & INSULATORS Conductors are materials that allow an electric current to flow through them easily, while insulators are materials that resist the flow of electric current. 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) Examples of Conductors: Rubber Glass Plastic Examples of Insulators: Air Wood Paper

11. ELECTRIC CIRCUITS ENERGY SOURCE LOAD SWITCH WIRES PARTS OF A CIRCUIT 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 through a closed circuit. Load: A component in a circuit that consumes electrical energy to perform a function, such as generating light or 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 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.

12. TYPES OF CIRCUITS CURRENT FLOWS THROUGH A CLOSED CIRCUIT, A LOOP WITH NO BREAKS, BUT AN OPEN CIRCUIT HAS A BREAK AND STOPS THE CURRENT FLOW. There are several options for connecting multiple loads in a circuit. Here are the two of the most common approaches: Series circuit: This involves connecting the loads in a line or series, allowing the current to flow from one load to the next in a single path. Parallel circuit: Here, the loads divide the current amount of the different devices, creating a parallel connection. SERIES PARALLEL

13. V I R OHM'S LAW Ohm's Law describes the relationship between electric current and voltage in a conductor, stating that the amount of electric current flowing through a conductor is directly proportional to the voltage that is causing the current to flow. I is the current (measured in amperes) V is the voltage (measured in volts) R is the resistance of the conductor (measured in ohms) Divide V by R to find the current. Divide V by I to find resistance.

14. A force that can attract or repel certain materials, such as iron, and is caused by the movement of electric charges within certain objects, like magnets or electric currents. WHAT IS MAGNETISM? Magnets attract iron and have two poles, a negative and a positive pole, where the magnetic force is strongest. All magnets share these properties. LIKE CHARGES REPEL UNLIKE CHARGES ATTRACT N S N N N N N S S S S S

15. MAGNETIC FIELD THE REGION AROUND A MAGNET THAT IS AFFECTED BY MAGNETIC FORCES. N S WHAT DO YOU THINK IT MIGHT LOOK LIKE?

16. N S MAGNETIC FIELD THE REGION AROUND A MAGNET THAT IS AFFECTED BY MAGNETIC FORCES.

17. 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. DID YOU KNOW?

18. 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. ELECTROMAGNETISM Physicist Hans Christian Oersted was the first to discover that electric current produces a magnetic field around a wire. Electromagnets are used in electric motors, loudspeakers, television sets, doorbells, trains, and many other devices. T he process of creating an electric current by moving a conductor through a magnetic field or by varying the magnetic field around it. T he majority of the electricity supplied to homes is generated using electromagnetic induction. Faraday's Electromagnetic Induction