Lemon batteries

The so-called voltaic cell can be made up by a lemon, by a potato, or even by hands with two metals . Millions of these cells are used every day in telephones, computers, walk-man and clocks.

The lemon battery is an example of voltaic cell: electro-chemical reactions generate electric current. The little plates (of copper and zinc) are the electrodes. Electrolyte is a watery solution of different acids which can be found in every fruit or vegetable.