Why does potato clock work

How long a potato battery will last depends on a lot of things. First, it will only be "used up" if it's actually hooked up to a wire. If it's not hooked up to a wire, it will theoretically last until the potato goes bad. Also, it depends on how much zinc you have, because the zinc gets used up in the reaction that powers the battery. If you're using a piece of metal that only has a little bit of zinc on it, then it won't last very long at all.

But if you use a big, solid piece of zinc, your battery could go for a really long time! It also depends on the potato - some work better than others. If you want to know exactly how long a specific potato will last, the only way to find out for sure. Not Helpful 10 Helpful A potato clock runs by converting chemical energy into electrical energy, which is then used to power the clock.

The potato, in combination with the zinc and copper strips which act as electrodes , acts as a battery. Not Helpful 18 Helpful Each potato assembly is a cell, producing a certain voltage. In order to have enough voltage to power the clock, you need two cells or potatoes in series. Not Helpful 5 Helpful The best potato to use in terms of more and longer power is the Jersey Royal Potato.

The second best is the Red Potato. Boiling your potatoes also helps bring the power up for your clock. Not Helpful 4 Helpful 7. Yes, but it would have to be a penny made before ; those made after are made of zinc with a thin copper coating.

Not Helpful 4 Helpful 9. You can, but the penny would have to be from before because ones after that date are made with zinc and only have a slight copper coating. Not Helpful 0 Helpful 3. It could be but you need to ask what the judges are looking for by way of challenge and originality. Potato clocks are a nice project to do but they might not win the fair because they are a common choice and not particularly challenging.

Not Helpful 2 Helpful 2. Include your email address to get a message when this question is answered. By using this service, some information may be shared with YouTube. Do not eat the potatoes afterward. Helpful 0 Not Helpful 0. Young children should be supervised when performing this experiment—nails and wires are sharp and can cause injury if handled incorrectly.

Removal of batteries should also be supervised. Related wikiHows How to. How to. More References 7. About This Article.

Co-authored by:. Co-authors: Updated: October 21, Categories: Featured Articles Clocks. Article Summary X To make a potato clock, start by removing the batteries from a digital clock, and inserting a nail and a copper wire into opposite ends of 2 potatoes. Italiano: Costruire un Orologio a Patate. Deutsch: Eine Kartoffeluhr herstellen.

Thanks to all authors for creating a page that has been read , times. I need help in finding where to buy the low-voltage clocks - guidance there would be appreciated. But I also need them cheap for a school project, that might be too specialized for your intended audience.

Thank you, though. I will come back with other questions on other things! Rated this article:. More reader stories Hide reader stories. At around one-tenth the cost of a typical AA battery, a potato could supply power for cell phone and other personal electronics in poor, underdeveloped and remote regions without access to a power grid.

To be clear, the potato is not, in and of itself, an energy source. Numerous fruits rich in electrolytes like bananas and strawberries can also form this chemical reaction. They are the world's fourth most abundant food crop. Additionally, boiling the potato breaks down the resistance inherent in the dense flesh so that electrons can flow more freely, which significantly bumps up the overall electrical output.

Cutting the potato up into four or five pieces, they researchers found, made it even more efficient. The potato battery kit, which includes two metal electrodes and alligator clips, is easy to assemble and, some parts, such as the zinc cathode, can be inexpensively replaced. The finished device Rabinowitch came up with is designed so that a new boiled potato slice can be inserted in between the electrodes after the potato runs out of juice.

This potato battery works as follows: 1 The zinc atoms in contact with the potato dissolve in the presence of the acid. This causes some electrons to separate from the zinc atoms. As a result of this, positively charged zinc ions, and negatively charged electrons, are produced. They do this because they are attracted to the positive hydrogen ions in the potato, located on the copper side these hydrogen ions are there due to the acid content of the potato. Since the electrons cannot pass through the potato itself, they pass through the wire joining the zinc and copper strips.

These electrons then combine with these positive hydrogen ions on the copper side and produce hydrogen gas, which then bubbles away.