Magnetic Launcher
The activity's magnetic launcher, ready to go.Copyright 2009 Erik Wemlinger, Washington State University
Students explore electromagnetism and engineering concepts using optimization techniques to design an efficient magnetic launcher. Groups start by algebraically solving the equations of motion for the velocity at the time when a projectile leaves a launcher. Then they test three different launchers, in which the number of coils used is different, measuring the range and comparing the three designs. Based on these observations, students record similarities and differences and hypothesize on the underling physics. They are introduced to Faraday's law and Lenz's law to explain the physics behind the launcher. Students brainstorm how these principals might be applied to real-world engineering problems.
This activity introduces students to the idea of goal experimentation. In this case, the goal is to determine the time required to launch a projectile. In the process, students derive equations for analyzing experimental results, test different models for best performance, and then estimate how long it takes to launch the projectile. Then they relate these concepts to real-world engineering challenges.
After this activity, students should be able to:
- Find the direction of the magnetic field if the direction of the current is known.
- Determine the direction of an induced current if the direction changing magnetic field is known.
- Determine the time required to launch a projectile.
- Brainstorm real-world engineering applications of these principals.