A demonstration apparatus is described suitable for use in a large lecture hall, in which the ‘‘pinch effect’’ applied to an empty aluminum soft drink can provides a dramatic and instructive example of induction and of the repulsion of oppositely directed current elements. The can is placed in a coil into which a short pulse of electrical current is driven from a charged capacitor. The current in the primary coil induces an oppositely directed current in the can wall, and the portion of the can under the coil is driven violently inward, pinching the can down to form a waist, or with a larger charge on the storage capacitor, separating it into two pieces.