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Activity Name Electricity and Magnetism Grades 4-8 Suggested Activity Time Preparation Time 20-30 min For each group: one copy of SDO image (see page 4), two D batteries, one 2“D” battery holder, one 10-15 min long nail (approx. 3”), 30 paper clips, 3-4 ft. insulated wire with alligator clips on each end Materials* Objectives- Students will be able to: • perform an experiment using an electromagnet • explain the relationship between electricity and magnetism • recognize how electromagnetism relates to solar storms Description: In small groups, students will build electromagnets and discover how many paper clips they can pick up with their device. Students will learn how electricity and magnetism are interrelated, and how they relate to activity on the Sun. How to Prepare: Cut the insulated wire into lengths of 3-4 ft so that there is one for each group. Attach an alligator clip to each end of the 3-4 ft. long insulated wires (see pictures to right). Make sure that the batteries are not in the battery holders; they will drain more easily if left in the holders. Print out one copy per group of the SDO image on page 4 of this lesson. Background Information: Electromagnetism is an important concept that scientists need to understand when studying the Sun. Electromagnetic activity on the Sun can lead to solar storms (also known as geomagnetic storms), which cause the Earth to be flooded by radiation from charged particles. Although this radiation is sometimes the cause of beautiful auroras, it is also a significant threat to our power grids and other systems on Earth. NASA scientists, such as those working on the Solar Dynamics Observatory (SDO) mission, study the Sun’s electromagnetic activity in hopes that they can eventually predict solar storms and prevent these problems. In this activity, students will build and use an electromagnet. When an electric current passes through a wire, it creates a magnetic field that looks like circles around the wire. This is called an electromagnet because the electric current creates the magnetic field. When a wire carrying electricity is wrapped around a nail (or twisted into a coil), it is called a solenoid. The magnetic field twists with the coiled wire, causing the magnetic field lines to concentrate inside the coil. This creates a powerful magnetic field inside the coil. When a steel nail is placed inside the coil, the magnetic field inside the coil aligns the tiny magnetic fields in the steel in one direction (all the north poles point the same way). These little fields all pointing in the same direction add to the coil and make the magnet strong enough to pick up some objects. Vocabulary: - current - electricity - electromagnet - magnetism - solar storm (or geomagnetic storm) Directions: 1. Ask students what they know about electricity and magnetism. How do they use them in their day-to-day life? What does electromagnetism mean? (To introduce this concept to students, you can show them a video on the topic. See Resources section for links to videos.) 2. Tell students that electromagnetism is an important concept to know when studying the Sun, and that they will build an electromagnet to better understand the concept. Break the class into small groups and hand out the materials. (You may want to keep one set of materials for yourself to model the procedure for them.) 3. Ask students to try to pick up paper clips with the nail. Does it work? Why not? 4. Instruct students to wrap the insulated wire around the nail. (Note: Make sure students wrap the wire around the nail tightly at least 40 times, otherwise it may not work very well. The tighter they make the coil, the stronger the electromagnet will be.) 5. Tell students to make sure their batteries are not in their battery packs yet. Leaving the wire coiled on the nail, have students clip one end of the coiled wire (using the alligator clip) to the wire protruding from one side of the battery pack. Have them clip the other end of the coiled wire to the wire protruding from the other side of the battery pack (see picture below). 8. Ask students if they think the nail will pick up paper clips now (without putting the batteries in the battery pack). Does the presence of the coiled wire make the nail a magnet? Have them place the nail over the paper clips to see for themselves that it does not. 9. Ask students to predict what will happen when they put the battery in the battery pack and then try to pick up paper clips with the nail. Will the nail pick up paper clips? Why or why not? If so, how many? 10. Have students load their batteries into their battery packs. Have them place the nail over the paper clips. Why did the nail act as a magnet when the battery was added? 11. Explain that the battery acts an electrical pump and moves electrons through the wire, creating an electric current. As the current passes through the coiled wire, it creates a magnetic field, thus causing the nail to act as a magnet. (See Background Information and Resources for more information.) 12. (optional) Allow groups to compete against each other and see how many paper clips they can pick up with their electromagnets. Have students record on the board the number of paper clips they picked up and the number of times they wrapped the wire around the nail. Ask them: Do you see a connection? Does the number of times you wrap the wire around the nail affect how many paper clips you can pick up? 13. Reinforce to students that electricity and magnetism influence solar activity, and scientists are studying how this activity affects us here on Earth. Have students look at the SDO image on page 4. Discuss with them how this image was taken by SDO and shows the levels of magnetic activity on the Sun. The black and white areas in the image indicate that there is a high level of magnetic activity, and the gray areas indicate there is no magnetic activity (for more on magnetograms, see the Stanford Solar Center link under Resources below). The white lines in the image follow the many magnetic field lines around the Sun. Similar to what occurs with an electromagnet, the Sun’s magnetic fields are caused by charged particles flowing in and around the Sun. 14. Explain to students that areas of intense magnetic activity on the Sun are where solar storms occur and these can affect us on Earth. Show students the National Geographic video on Electromagnetic Sun Storms (see link under Resources). Afterwards, discuss why it is important to study electromagnetism and how it influences the Sun-Earth relationship (see Background Information). National Science Education Standards addressed: K-4: Content Standard B: As a result of their activities in grades K-4, all students should develop an understanding of light, heat, electricity, and magnetism, 3: Electricity in circuits can produce light, heat, sound, and magnetic effects. Electrical circuits require a complete loop through which an electrical current can pass. 5-8: Content Standard B: As a result of their activities in grades 5 – 8, all students should develop an understanding of transfer of energy, 4: Electrical circuits provide a means of transferring electrical energy when heat, light, sound, and chemical changes are produced. Resources: • 100 Greatest Discoveries With Bill Nye—Electromagnetism (video): http://www.youtube.com/watch?v=6sP6smOUQj8 • Bill Nye the Science Guy—Magnetism (video): http://www.youtube.com/watch?v=RdROOcnr1q4&feature=related • How Stuff Works—Electromagnets: http://science.howstuffworks.com/electromagnet.htm • NASA—Experimenting with Electromagnets (video): http://www.nasa.gov/mov/255366main_137_Electromagnets.mov • NASA—Magnetic Fields: http://www-istp.gsfc.nasa.gov/Education/wmfield.html • NASA—Magnetism from A to B: http://SunEarthday.gsfc.nasa.gov/2010/TTT/71.php • NASA—The Key to Understanding the Sun: http://solarscience.msfc.nasa.gov/the_key.shtml • National Geographic—Electromagnetic Sun Storms (video): http://www.youtube.com/watch?v=W_cLSvP9qSU • Stanford Solar Center—Solar Magnetograms: http://solar-center.stanford.edu/solar-images/magnetograms.html • UC Berkeley Space Sciences Laboratory—Exploring Magnetism Teacher Guides: http://cse.ssl.berkeley.edu/SEGwayed/lessons/exploring_magnetism *Take out the batteries when not in use to prevent them from draining quickly. Also, make sure to use insulated wire otherwise the experiment will not work. Most items can be purchased online at radioshack.com and other sites. Radio Shack catalog numbers are as follows: 2 “D” battery holder #270-386, insulated wire #278-503, alligator clips #270-380. Magnetic Fields of the Sun Magnetogram image of the Sun from 10/11/2011