a) Understand the conditions for lighting a light bulb by connecting it to batteries with wires to make it illuminate.

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1 This area deals with simple electric circuits and electromagnets. In this area, students learn about electricity for the first time and build an electromagnet and a simple circuit to compare the brightness of a light bulb. This area helps students learn how a light bulb on in an electric circuit illuminates, understand currents by comparing the brightness of a light bulb according to the way the bulb is connected to the circuit. Students also learn how to conserve electricity and use it safely.

2 The grade 6 English science unit, The Effects of Electricity, meets the academic content standards set in the Korean curriculum, which state students should: a) Understand the conditions for lighting a light bulb by connecting it to batteries with wires to make it illuminate. b) Compare brightness according to the manner of connecting the bulb to the circuit. c) Learn how to safely and efficiently use electricity and put the learning into practice. d) Make an electromagnet using wires through which a current is flowing.

3 An electric circuit is a continuous loop that allows an electrical current to flow. It needs a power source, like a battery, to help keep the current flowing. The circuit needs to be closed, which means that all the components need to be connected. If it is open or broken, then the electrical current cannot flow. Different components can be added to the circuit. For example, a light bulb changes the electrical energy into light and heat. A buzzer changes the electrical energy into sound energy. These two components are often used in the popular Electrik Shock game. 4 alligator clip wires Lamp 2 D batteries Metal wire Electrik Shock game 1. Make an open circuit like the example above. It should be similar to the shock games that can be bought from the shops. 2. Take turns at trying to get your hoop from one end to the other end without touching the wire. 3. If you touch the wire, your turn is over. The next person attempts to complete the game. What happened? Draw your electric circuit design below. 1. What happened when the metal loop touched the wire? 2. Why did this happen?

4 In some materials, like metals, the electrons are able to move very freely. An electric current is the movement of electrons. A material that allows an electric current to flow through it is called a conductor. A material that does not allow an electric current to flow through it is called an insulator. 4 alligator clip wires Light D battery Switch Different objects The wires used in appliances are insulated. These insulated wires are electrical wires, usually made from copper, that are covered with plastic. The electrons can flow through the wire, but not the cover. Conductor (metal) Insulator (plastic) 1. Make an open circuit like the example above. 2. Connect different objects to the section that is open. 3. Push the switch and see if the light turns on. What happened? Complete the chart. Objects that allowed the light to turn on Objects that couldn t turn the light on 1. What is a conductor? Give an example of a material that is a conductor. 2. What is an insulator? Give an example of a material that is an insulator.

5 A series circuit means that there is only one path for the electric current to flow through. The parts are connected one after the other. If one part of the electric circuit is broken, then no electric current can flow. 6 alligator clip wires 2 lights 2 D batteries A parallel circuit means that there is more than one path for the electric current to flow through. If one path is broken, the electric current can still go through the other working path. A series circuit has only one path. If one light is broken, the other light won t work either. A parallel circuit has more than one path, so if one light is broken, the other light will still work. 1. Use the two lights and make a series circuit. 2. Use the two lights and make a parallel circuit. What happened? Draw the circuits you made. Series Circuit 3. Break one of the lights in each circuit and see what happens to the other light. Parallel Circuit 1. What happened when you broke one light in the series circuit? Why? 2. What happened when you broke one light in the parallel circuit? Why? 3. Which circuit had the brightest lights? Use other resources to help explain why this happens.

6 When we draw electric circuit parts, we use circuit symbols. Make sure that the wire lines are straight lines like the examples below. 6 alligator clip wires 2 lights 2 D batteries 2 switches Motor Buzzer a) b) c) d) 1. Look at the four circuit diagrams and make the circuits. 1. Two different symbols can be used to show a light/lamp. Draw them. 2. What do you need to be careful about when drawing the wires in a circuit diagram? 3. Draw some original circuit diagrams below. See if your friends can make them using the supplies you already have.

7 As electric current flows through a wire, it makes a magnetic field around it. This is known as electromagnetism. The magnetic field can be made stronger if the wire is wrapped around in a coil. The coils acts like a magnet. Nail Long, thin wire Paperclips 2 D batteries Electromagnets are used in many ways. They are used in switches, bells. Powerful electromagnets are also used to lift heavy metal objects. When the electric current is turned off, the electromagnet stops working. An electric bell uses an electromagnet. An industrial electromagnet lifting scrap metal. 1. Wrap the wire around the nail according to the number of wraps in the chart. 2. Connect the batteries to the wires. 3. Try to pick up as many paperclips as you can for all the different number of wraps. What happened? Complete the chart. Draw a picture of your electromagnet. Number of wraps Paperclips picked up 1. Which number of wire wraps picked up the most paperclips? Why? 2. How are electromagnets used in everyday life?

8 Electricity is a very useful energy source, but it is also very dangerous. It is important to know about basic safety concepts when using electricity. Electricity can cause serious injuries or even death if it is used incorrectly. Using electrical appliances around water can cause fires, explosions or electrocutions. Putting too many appliances in the same outlet can cause fires. Putting metal objects in the outlet or electrical appliance could electrocute you. Covering electrical cords with rugs can start fires. Flying a kite near power lines can also lead to electrocution. Colored pencils Markers Poster paper 1. Brainstorm some ideas about what you should or shouldn t do when using electricity. 2. Choose your best idea and create a safety poster. What happened? Brainstorm some safety issues. 1. List your three top safety rules when using electricity. a) b) c)

9 Salty water conducts electricity. In order to make play dough, you usually dissolve some salt in water. This is why an electric current is able to flow through the play dough. Play dough can be made in many ways, but below is a nice simple method. Mix 100 g of salt, 100 g of flour and 4 teaspoons of cream of tartar in a bowl. Add some food coloring to 100 ml of water. Pour the colored water and powder mixture into a saucepan that is on a cooker. Keep stirring the hot mixture until it turns into thick dough. Play dough LED s (a variety) 4 AA batteries 2 wires You can be creative with your electrical play dough, like the people at ABC Science. 1. Connect 4 AA batteries together. Connect two wires to the ends of these batteries. 2. Roll the play dough so it looks like a snake. Cut it in half. Put the wires into the play dough. 3. Complete the electrical circuit by putting an LED between the two play dough snakes. What happened? Draw a picture of your electrical play dough working. 1. Why does play dough conduct electricity? 2. What happens to the LED when you make the play dough wires shorter? 3. Why do you think this happens?