Potato Clock

Reading the above lines, you must have guessed how confused I was, when I heard about the potato clock. But then I dig up some information on the Internet and guess what, I came up with some really interesting facts about this 'veg-machine'. So I thought why not share it with you guys. A potato clock is a time keeping device or clock that is powered by a potato!..

Who Was the Genius Behind It?

It was in the year 1983 that the world got to witness yet another amazing scientific invention - the potato clock. It was William A. Borst who came up with it while he was assisting his step daughter in setting up a science fair project.

How to Build One

Materials Required

• Potatoes - 2
• Copper wires, short length - 2
• Nails, galvanized - 2
• Alligator clips - 3
• LED (light emitting diode) clock, low-voltage - 1

Instructions

• Alright, if present, first remove the batteries of the LED clock.
• Now get the galvanized nails and insert one in each potato.
• Once done with it, insert a copper wire into each potato. Ensure that you insert it at a place far away from the inserted nail.
• Time to use the alligators! I mean alligator clips. Using the clip, make a connection between the copper wire of one potato (say A) and the positive (+) terminal of the empty battery space of the clock.
• Get another alligator clip, and this time connect the galvanized nail of the potato (say B) to the negative (-) terminal of the clock.
• So what's left? The other galvanized nail of potato A and the other wire of potato B. So use the third alligator clip to make a connection between these two parts to complete the circuit. And voila! Tick! Tick Tick! Your clock is ready for action.

Easy isn't it? Now let us see how does the whole process actually take place.

Working Mechanism

As you can infer from the above explanation, making a potato clock for a science fair project is fairly easy. But equally important is to be versed with the working of the whole thing. A potato can be considered as an electrochemical battery, with an in-built electromotive force. And this force has the ability to mobilize electric current. The copper wire that we have used serves the purpose to cause the elections to move, and convert the electrochemical energy into a low-voltage electrical energy. And this very energy is used to run the clock.

The galvanized nails that have been used act as the anode (positive terminal) of the entire circuit. When it is inserted into the potato, the vegetable's phosphoric acid reacts with the zinc in the nail, and this causes zinc to lose 2 electrons from it. Now at the same time, the copper wire that has been inserted in the wire acts as the cathode. It also reacts with the acid, and hydrogen ions are produced as a result of the reaction. These ions absorb the released electrons from the zinc. And this whole process results in the generation of electricity which can be used to power low-voltage appliances like a clock, flashlight bulb, etc.

And before I conclude, did you know that eating mashed potatoes everyday helps you know what time it is without the help if a watch? Just kidding! Best of luck with the project!