This note describes a new modification of the falling magnet in a conducting tube1 demonstration (Fig. 1). In this version of the eddy current demonstration, thin-walled hobby brass tubing is used rather than the traditional copper pipe. These tubes come in nesting size increments that allow a slip fit for the next larger size. The typical demonstration now goes by stages, increasing the wall thickness with each drop of the magnet.

The thin wall offers greater resistance to the induced current, and since brass is not as good a conductor as copper, a single tube only modestly retards the falling magnet. The effect is still clearly visible, but is not as dramatic as in the standard demonstration. Adding successive layers of tubing significantly reduces the net resistance of the eddy current path, and the drop time is visibly increased as each new layer is added.

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