WHAT TO DO: Go into the Red Mode and place the Coil on top of the Magnet.
NOTICE: Depending on the placement of the yellow slider, the Coil launches itself off of the Magnet every set number of seconds.
LEARN: The Coil launches itself because it becomes an electromagnet. While the Coil normally does not stick to the Magnet, when it receives electricity it momentarily becomes a Magnet. This gives the Coil the opportunity to attract and repel from the Magnet, causing for it to launch off when it receives electricity.
What is a magnet? For this lesson you can use whatever class materials are available in your state for teaching about magnets. Make sure that you highlight the importance of the North and South poles and the attraction and repulsion between them.
Hand out a Magnet with the blue base from the BOSEbuild kit to each student or pair of students.
TIP: Only hand out the Magnet from the kit at this time.
After doing a demo on magnetic fields, attraction and repulsion, ask the students “What do magnets stick to?” Have them search around the classroom, touching the Magnet to objects to test if anything is attracted to it. Make sure that US pennies are included in the items that they test. Have them record the items that stick and the ones that don’t in a chart in their science notebooks.
Gather the class back together and ask them what they observed. Discuss with them what objects and materials the Magnets stick to. Talk about which metals stick, which ones don’t, and why. Use this as an opportunity to introduce the copper Coil from the BOSEbuild kit and hand one out to each student/pair. Ask the students to create a hypothesis about whether the Coil will be attracted to the Magnet.
After they discover that the Coil does not stick to the Magnet, have them compare it to other materials they tested; what is it similar to? Discuss how the Coil and pennies are both contain copper, and that copper is not attracted to magnets*. List other metals that magnets do or do not stick to and see if they can identify any of the objects that they tested before.
(*US pennies are made of both copper and zinc. Zinc is another metal that does not stick to magnets.)
After they have identified objects, hand out a Control Panel and Power Adapter to groups of 2-4 students.
TIP: Make sure that each group is located near an outlet.
Have them plug the adapter into the wall, and then plug the other end into the port labeled “Power” on the Control Panel. A white light should appear near the top of the Control Panel.
Now instruct the students to connect the Coil into the appropriate port.
TIP: Show them that the Yellow Plug connected to the Coil has three circles on it, then tell them to plug it into the port on the Control Panel that also has three circles above it. Make sure that they plug it in all the way.
The students should now be ready to start the experiment. Instruct the students to place the Coil on the Magnet, with the yellow base down. After having the students move the Yellow Slider on the Control Panel all the way to the left, tell them to press the Yellow Button on the Control Panel one time to change it to the Red Mode. The Coil will jump off of the Magnet. Encourage the students to place the Coil back on the Magnet, observe what is happening, and record it in their science notebooks. The Coil will jump off every 3 seconds, which is just enough time for the students to put it back each time.
Explain that the Coil has become an electromagnet. It “jumps” because an electrical pulse is being sent from the Control Panel, through the wire, into the Coil. Copper is a material that becomes a magnet when electricity is flowing through it. Each time the pulse is sent to the Coil, the copper becomes magnetic, repelling it away from the Magnet and making it fly off.
Encourage the students to move the Yellow Slider to the right. As they move the slider the Coil jumps less frequently. Let them experiment with the time variation as they move the Yellow Slider left and right. (If the Yellow Slider is in the rightmost position it will jump every 10 seconds)
Moving on from the Red Mode, have the students change the Control Panel to the Yellow Mode by pressing the Yellow Button again. (Make sure that the slider is pushed to the far left) The Yellow Mode will cause the Coil to move up and down on the Magnet at different rates according to the positioning of the Yellow Slider, getting faster as the slide is moved towards the right. Have the students trace the motion of the Coil on a piece of paper when the Slider is positioned to the far left. Repeat when it is positioned to the far right. Go through and help them label their drawings with wavelength, frequency, peak, trough, and amplitude. See the example below.
- The rate of the jumps is called frequency
- Frequency is a measurement of “bounces” per second
- Peaks are at the highest points of waves and troughs are at the lowest points of waves
- Wavelength is the distance between 2 peaks
- Amplitude is the height difference between a peak and a trough
Ask them questions such as; “Which has a shorter wavelength? Which has higher frequency?”
Return to the Control Panel and have the students watch the motion of the coil again, this time asking them which has a shorter wavelength when changing the position of the Slider (far left has a longer wavelength). Using what they now know about magnets and their poles, have them hypothesize about what is happening to the Coil that causes to jump. They should make the connection that the Coil, when receiving electricity, switches between acting like the north pole is pointing up and the south pole is pointing up. This means it alternates between being attracted to the Magnet and repelling away from the Magnet, causing the up and down motion.
Next Activity: Measurements