ZAPPER
engineering 2011 
I was asked to design and build a classroom experiment for an Electromagnetism class at Stanford. The demonstration consists of a very large capacitor (500F) which is charged to a maximum of 10kV. Once charged, the capacitor is discharged rapidly in various circuit elements, to produce extremely large forces. In its first incarnation the capacitor is discharged into a small coil that winds around a coin. The sudden current increase in the coil induces a large current in the coin that acts like the secondary of a transformer. The magnetic force makes the coil explode and the coin implode, causing the diameter of the coin to shrink substantially. This yields a spectacular demonstration of electromagnetic induction and forces. The demonstration is now being used in Physics 45 at Stanford University.
I was asked to design and build a classroom experiment for an Electromagnetism class at Stanford. The demonstration consists of a very large capacitor (500F) which is charged to a maximum of 10kV. Once charged, the capacitor is discharged rapidly in various circuit elements, to produce extremely large forces. In its first incarnation the capacitor is discharged into a small coil that winds around a coin. The sudden current increase in the coil induces a large current in the coin that acts like the secondary of a transformer. The magnetic force makes the coil explode and the coin implode, causing the diameter of the coin to shrink substantially. This yields a spectacular demonstration of electromagnetic induction and forces. The demonstration is now being used in Physics 45 at Stanford University.