Students will construct an electromagnet and explain how it works.
Magnetism by John Woodruff
Magnets and Electricity by Karen Lee Siepak
Physics for Kid: 49 Experiments with Electricity and Magnetism by Robert W. Wood
An electromagnet is a temporary magnet formed when electric current flows through a wire or other conductor.Most electromagnets consist of a wire wound around an iron core.In 1820, Hans Oersted discovered that an electric current produces a magnetic field.In 1825, English electrician William Sturgeon showed that by adding an iron core, the coil's magnetic field is strengthened. In the late 1820s, American physicist Joseph Henry built the first practical electromagnet.
Invitation to Learn:
Dump some straight pins or paper clips on the table. Ask one of the students to volunteer to gently touch a nail to the pile of pins. Ask the student if the nail is acting like a magnet. (It should not.) Next, have another student touch a bar magnet or similar permanent magnet to the pins. Ask the student if the bar is acting like a magnet. (Obviously, it should.) Tell the students that it is possible to make the nail act just like the bar magnet.
This may be done as a class demonstration, or each student could make his/her own electromagnet.
Conclusion: When an electric current moves in one direction through a wire,
a magnetic field is created around the wire. When the wire is wrapped around
an object to form a coil, the magnetic field around each wire is aligned right
next to the field of the adjacent wires. They all work together to form a much
stronger, single magnetic field.
Have each student construct an electromagnet and explain how it works. If materials are not available for all students, have them draw a picture of an electromagnet and explain how it works.
This lesson is part of the Fifth Grade Science Teacher Resource Book (TRB3) http://www.usoe.org/curr/science/core/5th/TRB5/. The TRB3 is designed to be your textbook in teaching science curriculum to your students. This book covers all the objectives of each standard and benchmark. If taught efficiently, a student should do well on the End-of-Level (CRT) tests. The TRB3 is designed for teachers who know very little about science, as well as for teachers who have a broad understanding of science.