E 6.5 Batteries and Electrolysis.

Lead-acid demonstration battery, charge and discharge Zinc-copper-acid battery Cut-away dry cell Batteries in series and parallel can be demonstrated Electrolysis apparatus Lemon cell - a copper and zinc nail pushed into a lemon will produce about 0.9 V on a meter. In Two Lemon Power two lemon cells are hooked in series and the charge accumulated in a 100,000 mfd capacitor. After a half-hour or so of accumulation, the device will run a small propeller for a few seconds. Bring your own lemons or give us advance notice. Suggested by Kimberley Willis.