Learning Objectives I can describe the parts of an electric circuit. I can distinguish between open & closed circuits. I can distinguish between a series circuit and a parallel circuit. I can describe safety precautions people should use in lightning storms and operating appliances.

Ohio New Learning Standards for Science Ohio 7th Grade, Physical Science #3 (7.PS.3) – Energy can be transferred through a variety of ways.

Lesson Opener

Unit 8, Lesson 6 – Electric Circuits What are the parts of an electric circuit? - an electric circuit is a complete, closed path through which electric charges can flow - all electric circuits contain three basic parts: an energy source, an electrical conductor, & a load - the energy source converts some type of energy, such as chemical energy, into electrical energy

Unit 8, Lesson 6 – Electric Circuits - examples of energy sources could be a battery, solar panels, wind turbines, and nuclear power plants

Unit 8, Lesson 6 – Electric Circuits - the materials in which electric charges can move easily are called electrical conductors - copper wire is a fantastic conductor! - most conductors are covered with insulators to prevent electrical shock

Unit 8, Lesson 6 – Electric Circuits - lastly, all circuits have a load, which is a device (light bulb, computer, flat screen, fan, etc…) that uses electrical energy to operate Complete #7, pg.601

Unit 8, Lesson 6 – Electric Circuits 1. cd player 2. digital clock 3. cell phone 4. computer 5. fan 6. lamp 7. electric bass guitar

Unit 8, Lesson 6 – Electric Circuits How are electric circuits modeled? - to make an electric circuit, you only need three basic parts: an energy source, an electrical conductor, and a load - since most circuits have more than one load, circuit diagrams are often used to display their arrangement for engineers and electricians

Unit 8, Lesson 6 – Electric Circuits a wire is shown as a line the load is represented by a zigzag line parallel lines show the energy source two open circles is an open switch two closed circles is a closed switch

Unit 8, Lesson 6 – Electric Circuits How does current stop and start? - electric charges move continuously in the closed loop of an electric circuit - opening a switch stops the charges from moving, but closing the switch creates a closed loop, allowing the charges to flow Complete #9, pg.603

Unit 8, Lesson 6 – Electric Circuits

Unit 8, Lesson 6 – Electric Circuits Complete #10, pg.603

Unit 8, Lesson 6 – Electric Circuits How do series circuits & parallel circuits differ? - simple electric circuits that contain one energy source & more than one load are classified as either a series circuit or a parallel circuit - in a series circuit, all parts are connected in a row that forms one path for the charges to follow - the current will be the same for all loads in a series circuit but if one of the loads fails, they all fail!

Unit 8, Lesson 6 – Electric Circuits

Unit 8, Lesson 6 – Electric Circuits - in a parallel circuit, electric charges have more than one path that they can follow - loads in a parallel circuit are connected side by side, so if one of them fails, the rest will still work! - the current in a parallel circuit can be different for all the loads, but they all receive the same voltage What circuit would be best for Christmas lights? Answer: Parallel Circuit!

Unit 8, Lesson 6 – Electric Circuits

Unit 8, Lesson 6 – Electric Circuits Complete #12, pgs.604 & 605

Unit 8, Lesson 6 – Electric Circuits Complete #12, pgs.604 & 605

What is an electrical circuit? What Are Circuits Worksheet accompanies this slide.

Unit 8, Lesson 6 – Electric Circuits How can I use electricity safely? - stay away from places where there is high-voltage electrical equipment & avoid using electrical equipment/appliances near water!!!!

Unit 8, Lesson 6 – Electric Circuits - be aware of your surroundings at all times! People have been electrocuted in swimming pools due to electrified water from broken lights Rachel Rosoff (17) died in 2016

Unit 8, Lesson 6 – Electric Circuits - damage to wires can cause a “short circuit,” in which charges do not pass through all the loads (current increases and wires can get hot enough to start fires) - fuses, circuit breakers, & ground fault circuit interrupters (GFCIs) are safety devices that act like switches to turn off current

Unit 8, Lesson 6 – Electric Circuits - when lightning strikes, electric charges can travel between a cloud and the ground - lightning usually strikes taller objects, so stay away from trees, monuments, and tops of buildings - most of the taller buildings & monuments have lightning rods, which provide direct paths to the ground for the electrical charges to flow!

Unit 8, Lesson 6 – Electric Circuits Lightning striking a tree in Kansas

Unit 8, Lesson 6 – Electric Circuits Lightning striking the “Christ the Redeemer” monument in Rio de Janeiro, Brazil

Unit 8, Lesson 6 – Electric Circuits Lightning striking downtown Dallas, Texas

Unit 8, Lesson 6 – Electric Circuits Lightning striking the Burj Khalifa in downtown Dubai, United Arab Emirates (U.A.E.)

Visual Summary

Exit Question How does a lightning rod protect a building from lightning damage?