Electromagnetism Project
Flip on the lights and it is there….turn the car key or push the power button on your iPod and electricity is summoned to help out in just about every area of our lives. But, this readily available energy was not always accessible or understood. Electricity, as you might recall from chemistry, is simply the flow of electrons. However, JJ Thomson did not discover the particle until the investigation of electricity was well underway!
The work of Hans Christian Oersted (the scientist who first confirmed that there is a relationship between magnetic fields and electricity as it flows through a wire) led to revolutionary breakthroughs in our understanding of electromagnetism. In the 1820’s, Michael Faraday took advantage of this interaction and built the first electric motor. Thomas Edison later invented the incandescent light bulb and which paved the way for the electrical infrastructure in the United States, bringing electricity into homes.
Whether it is in your car, your phone, or your ipod, you rely on speakers to hear your favorite tunes all of the time. The physics of static electricity, current electricity, and magnetism dictate how speakers work. Why are Dr. Dre Beats and Skullcandy headphones so good? How can you use your knowledge of physics to construct a homemade speaker from readily available items? How can you use the physics of electricity and magnetism to transform electrical current into sound that we can hear?
Teams of three people will build an iPod speaker designed to provide optimal loudness and audio quality. Projects will be evaluated based on your speaker’s performance and write-up.
Specifications:
A. Materials available to build with are: AWG 32 magnet wire, a 0.5” x 0.25” Neodymium magnet, cardboard, and an assortment of cups (if you would like additional materials, please bring them in!).
B. An ipod jack is available in the classroom for testing.
Procedural Guide:
A. Your group will do research on how to make a homemade speaker. Speaker performance will vary dramatically based on the materials chosen as well as the shape and construction of the cone and enclosure. It will be up to your group to determine what approach to this activity you wish to take.
B. Construct and optimize your final speaker configuration. Write a short report (instructions are below).
Design and Report:
How can we construct a homemade speaker?
Speakers will be evaluated based on their volume and audio quality. Several websites will be provided (at a later time) to help educate you on speaker design fundamentals and perhaps inspire you to come up with a particularly innovative design. If you need additional materials (not located in the classroom), feel free to bring them in. You are also welcome to pre-test your speaker before the due date. The use of manufactured speakers or speaker components is not allowed.
Groups may consist of no more than three students. Along with building a speaker, your group needs to explain the physics concepts that make the speaker work to a typical high school student. Your brief write-up may be in any form that is appropriate, including a report, a pamphlet, or it may take the form of a video, poster, etc. Your entire write-up must be your group’s own work.
Resources - click the links below for instructions on how to make a homemade speaker
· Plate Homemade Speaker Instructions