祥語

5月,參加南瓜田的科學實驗報告,自己寫稿,上台報告

Hi everyone! My name is Sean Lai, and I am in AG4 Class. Michelle is my teacher. Today, we’re going to have some fun with science AND food, and you may be very surprised by what you see.

This is a potato. It is obviously a kind of food. But this is not only a type of food, it can act as a battery, too. To make this happen, you need a few things. You need 2 potatoes of course, and a knife to cut the potatoes. Not only this…you still need a wooden board, one small blue LED light, four pieces of zinc, 4 pieces of copper , and five test leads, or electrodes. Are you with me? Or do you think this is boring? Please say no! We are not done. This is a potato. It can make French fries, and chips, but also, it can make electricity. It is very interesting! Hang in there.

This is what you have to do. First, you cut the potato in half. Kids, don’t try this at home by yourself; it can be very unsafe! Now the next step is harder. You needed to poke two holes in two sides of each half potato, and most kids don’t think this is easy, at least if they like to keep their fingers. I’m very serious! I cut my finger when I first tried it. Then you’ll put one zinc piece and one copper piece inside each 1/2 potato.

Now, here comes the fun part! You put one side of the test lead so it touches the zinc and the other side so it touches the copper. You do this with three test leads and they should all work together. The last part is the easiest part: you connect one side of the test lead to the LED light and one side to both the copper and the zinc. When you put all these things together, when all of the test leads touch, it lights up the LED light. If you just leave it there, the light will continue to shine until the potato has no water left inside it.

A potato battery is an electrochemical battery, otherwise known as an electrochemical cell. Batteries generate electricity through a chemical reaction between two different electrodes and one electrolyte, and the electrolyte is different between the potato battery and regular battery. My potato light stayed on for a week. It is a very long time, and it can save you in the dark when you have these things nearby. A power failure will never leave you in darkness again. Not only potatoes can be used to make electricity; other foods such as lemons and oranges can make an LED light brighten a room in exactly the same way!! Also, when you add more potatoes to the circuit, they make an even stronger current.

You can this it at home. Now you know that some food can make electricity.                        

I hope that you enjoyed my speech presentation and that you have a new appreciation for our new friend, the potato. Thank You.