Induction in an Aluminum Can

Record ID: 
nw-000-000-002-068
First Name: 
automatic
Last Name: 
import
Primary Email: 
Language: 
en-US
Institution Name: 
Resource Published Date: 
Tuesday, December 30, 1969 - 19:00
Description: 

This activity demonstrates Lenz's Law, which states that an induced electromotive force generates a current that induces a counter magnetic field that opposes the magnetic field generating the current. In the demonstration, an empty aluminum can floats on water in a tray, such as a Petri dish. Students spin a magnet just inside the can without touching the can. The can begins to spin. Understanding what happens can be explained in steps: first, the twirling magnet creates an alternating magnetic field. Students can use a nearby compass to observe that the magnetic field is really changing. Second, the changing magnetic field permeates most things around it, including the aluminum can itself. A changing magnetic field will cause an electric current to flow when there is a closed loop of an electrically conducting material. Even though the aluminum can is not magnetic, it is metal and will conduct electricity. So the twirling magnet causes an electrical current to flow in the aluminum can. This is called an "induced current." Third, all electric currents create magnetic fields. So, in essence, the induced electrical current running through the can creates its very own magnetic field, making the aluminum can magnetic. This is activity four of "Exploring Magnetism." The guide includes science background information, student worksheets, glossary and related resources.

SMD Forum Primary: 
Heliophysics
Audience: 
Educator
Format: 
application/pdf
Mission Or Program: 
THEMIS
Keywords: 
Magnetism
Lenz's Law
Access Restrictions: 
Free access
Learning Time: 
30 to 45 minutes
Materials Cost: 
$1 - $5
Individual or Group: 
Per group of students
Instructional Strategies: 
Cues, questions, and advanced organizers
Discussions
Guided inquiry
Hands-on learning
Assessments: 
Alternative assessment
Benchmarks: 
http://asn.jesandco.org/resources/S2366785
http://asn.jesandco.org/resources/S2366796
Contributor: 
University of California, Berkeley
National Science Education Standards: 
True
Math Standards: 
False
Technology Standards: 
False
Geography Standards: 
False
Educational Level: 
Learning Time Comment: 
Learning time is estimated.
URL: 
http://cse.ssl.berkeley.edu/SEGwayed/lessons/exploring_magnetism/magnetism_and_electromagnetism/Guide_activity4.pdf
Image Url: 
680.jpg