Caution! High Voltage

My project will study the relationship between temperature and voltage output in a potato.
Ramy Zemmal
Grade 5


My hypothesis is If I raise the temperature of the potato, then this will result in a rise in the voltage output because electrons flow easier in warmer temperatures.


First, What is voltage???

Voltage is like a pressure that pushes electrons around.

What is a potato made of?

A potato is a vegetable that contains good amounts of carbs, fiber,

vitamin C, vitamin B6, potassium, and manganese.


What are electrons???

Electrons are particles and these electrons spin in

an orbit around the core (nucleus) of the atom.

The nucleus is made up of protons and neutrons.

Electrons are negatively charged particles.

Electrons move almost as fast as the speed of 


The reason why electrons move so fast is because they are trying to get from a negative electrode to a positive electrode.




How does temperature affect voltage?

When the potato is warmer, electrons can move easier, then more electrons moving makes more voltage. 


What is dry ice?

Dry ice is the solid form of carbon dioxide. It can reach temperatures

of -78.6℃.If you touch it with your bare hands, there is a 

high chance that you’ll get frostbite.




Manipulated variables: Temperature of the potato, Boiling water

Responding variable: volt output

Constant variables: Potato, Voltmeter, Dry ice



Step 1. Get all materials

Step 2. Insert zinc electrode and copper electrode in potato

Step 3. Put the potato in a cooler filled with dry ice and close the cooler

Step 4. Take the potato out after 20-30 mins

Step 5. Connect the probes to the alligator clips and connect the alligator clips to the zinc and copper electrodes

Step 6. Put the probe of the thermometer on the potato

Step 7. Look at the screen of voltmeter and thermometer and write down the measurements given on the screen

Step 8. Let the potato cool down a bit for like 1 minute

Step 9. Repeat steps 2 to 8



When I was at about -12℃ the voltage would increase very fast but the temperature would increase very slow the whole experiment. Later the voltage would slow down and it would go decrease sometimes. The voltage would sometimes change all the time so it was an estimate of the answer.




In my experiment electrons move slower when the temperature is lower. This happens because the ice almost freezes them and the electrons can't really move, also when the temperature is very low the voltage is almost at 0 because, again the electrons can't really move.




I was  incorrect because the voltage did not increase the whole time but kind of made a semi arch in my charts.It may have went up and down a little but it was maybe a human error.


Something that this can help the world with is powering things up. The potatoes that I tested all produced more than 1.5V/1500mV so it has the number of volts as a AA Duracell battery. This amount of voltage can power many things, for example, some toys, small machines, and more. If we can get the citric acid of the potato and somehow make it into a solid thing we can power so many things.

Sources Of Error

I had to make changes like I put the potato in hot water so it would get warmer faster, for example, the first time I used a hairdryer so the potato can get warmer faster but that messed up my observations so I used hot water instead.



Kiddle, Electron facts for kids, Retrieved from


Potatoes: Are they healthy or unhealthy? Retrieved from:


Science for kids, The atom, Retrieved from:


What is dry ice? Retrieved from: 


What is voltage? Retrieved from:



I would like to acknowledge my dad and Teacher for helping me doing my science fair.