Chapter 4 Lesson 3: Electromagnetism

Vocab. Match-Up Match the vocabulary words with their definition. electromagnet a magnet that only works when electricity is provided motor a device that changes electrical energy into mechanical energy generator a machine that produces electrical energy bu turning coils of wire around a powerful magnet 1. How does electric current flowing through a wire produce magnetism? It changes the wires into two magnets It produces a magnetic field around the wire It changes it into a permanent magnet 2. Why can an electromagnet be more useful than a permanent magnet, such as a bar magnet or a horseshoe magnet? An electromagnet can be turned on and off. An electromagnet uses much less energy. An electromagnet is small and lightweight. 3. How can you generate an electric current in a loop of wire? Place a magnet on top of the wire. Connect the loop of wire to a light bulb. Spin the loop of wire between the poles of a magnet. 4. Generators transform solar energy into electrical energy. true false 5. How do you make and electromagnet stronger? Use a stronger battery. Coil the wires more times around the iron nail. Use a larger metal object. All of the above. 6. Wind turbines can turn wind energy into electrical energy, and wind is a resource that will not run out. Inside the wind turbine, energy of motion from the wind- turns a metal coil around a plastic coil turns one magnet around another magnet turns coils of plastic around a giant magnet turns coils of metal wire around a giant magnet 7. Which tool can be used to find out whether a magnetic field is around? mirror compass microscope all of the above