1. Ch. 24: Electric Current and Circuits Vocabulary: electrical energy, electric current, circuit, closed circuit, conductor, closed circuit

2. Electric Circuits All electric circuits come in two basic flavors. They are either open or closed. Closed circuits are completely connected, and the electricity can flow. Open circuits have a spot or spots where they are not connected and will not allow electricity to flow.

3. Closed Circuits In a circuit we talk about the flow of electricity, it is called electric current. In the simple closed circuit from before the electricity flows out of the top section of the battery (positive end), through the wire, into the light bulb (making it light up), then into the next wire, and back into the bottom of the battery (negative end). If everything stay connected (closed) then the electricity will continue to flow. We use wires to carry electric current because they are good conductors. Conductors are materials that allow electricity to flow through them. Wires are usually made out of copper, because copper is an excellent conductor.

4. Open Circuits Open circuits do not allow electricity to flow. When a hole happens in the circuit, then the circuit opens and the electricity cannot flow back into the battery and the whole operation shuts down. This is not always a bad thing. Sometimes you don’t want a circuit to be closed all the time, like on a lamp, you want to be able to sleep sometime. A device called a switch can be placed inside the circuit that will open or close the circuit whenever you want.

5. Open Switch vs. Closed Switch

6. Electricity? The appliances in your house are too large to run on batteries. Instead the electricity is produced in a power plant and sent through wires into your house, powering everything that needs electricity where you live. REMEMBER! Electricity does not come from wires, it only travels through them.

7. Questions About Chapter 24 1.Why are switches installed into electric circuits? 2.Name two places that electricity comes from. 3.What are the two basic types of electric circuits? 4.What is electric current? 5.Draw a picture of a simple closed circuit. Include wire, a battery, and a light bulb.