Grade Level: 6th - 9th; Type: Physical Science
To see if an LED light can be powered by vegetables and/or fruits.
The purpose of this experiment is to determine whether there is enough energy stored in a fruit or a vegetable to power an LED light. This experiment can be taken further to determine how long a fruit or vegetable can power an LED for.
- How is energy stored in a fruit or vegetable?
- How to we measure this type of energy?
- How do we usually use the energy stored in plants?
- Where do plants get their energy from?
- How much energy is stored in a typical potato?
- How much energy is stored in the other fruits or vegetables you are using?
With the help of a few household items, a potato can be used to power a light bulb. All living organisms contain energy and it may be possible to tap into and use some of that energy in our everyday lives. Given that our main source of energy, fossil fuel, is in limited supply, it is important for scientists to explore the use of alternative energy sources. Many natural, green energies are already being used around the world, but there is still a lot to learn about utilizing alternative energy sources. By developing planet-friendly ways to draw energy from the world around us, we can decrease our use of polluting energy sources which will help keep the air, water and soil clean for future generations.
- LED light bulb
- Assorted fresh fruits and vegetables (i.e. carrot, apple, pear, squash, lemon)
- 1 potato
- 1 shiny penny
- 1 galvanized steel nail
- 2 eight inch lengths of copper wire
- A knife
The materials needed for this experiment can be found at the grocery store and at the hardware store.
- Begin by constructing a potato light. We already know that potatoes can be used to power LED lights, and setting up a working light in a potato will help you determine whether you are constructing the vegetable powered light correctly.
- Make an incision in one side of the potato just large enough for the penny to fit inside.
- Wrap one end of a piece of copper wire around the penny.
- Wrap one end of another piece of copper wire around the nail.
- Insert the penny into the slit you created for it, with the loose end of wire hanging out.
- Insert the nail into the other side of the potato with the loose end of wire hanging out.
- Do not allow the penny and nail to touch.
- Wrap the copper wire coming off the penny to the longer leg of the LED.
- Wrap the copper wire coming off the nail to the short leg of the LED.
- Observe the results.
- Repeat steps 2-10 with other vegetables or fruits.
Terms/Concepts: Green energy; Fossil fuel; Alternative energy; Potential energy; Filament; LED light