Aug. 20, 2009

Experiments With My Brother: Paper Magic and Sky Colors

by Betty Diop

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popbottleMy little brother, David, age eight, is interested in science and anything innovative. So we decided to do some Pop Bottle Science experiments. The first experiment we did was called Paper Magic. David was really excited as soon as he saw the pop bottle because it looked cool and he was curious about what we would do with it. I explained to him that we would need to fill a bucket with water. He was eager to do everything on his own and didn't really want my help at all.

We filled the bucket completely with water. Then I had him stuff a wadded-up newspaper section into the pop bottle. I checked to make sure it was nice and tight so when we put the bottle upside down, it wouldn't fall out. With a little guidance, David pushed the upside-down bottle into the water, making sure that it wasn't tilted, and left it in for a couple of seconds. I asked him to predict whether the paper would come back dry or wet. He said it would be wet.

When we pulled up the bottle, I lifted out the paper and we marveled at how dry it was. I asked David why it remained dry and he made a few guesses, like the size of the bottle, the fact that the water level wasn't high enough, or that he paper was too far down at the bottom. I explained the role air inside the pop bottle played in keeping the paper dry while pushing the water level up. He went on to tell me about an experiment he did at school with a battery and light bulb. Our experiment was a success and he had loads of fun!

Our second experiment was entitled Sky Colors. We used the same water from the bucket to fill the pop bottle two-thirds full of water. David measured out one teaspoon of milk and added it to the water as I stirred. I closed up the bottle and we grabbed a flashlight. We turned off all the lights to make the room really dark. I turned the flashlight on and held it at different angles.

Firstly, I placed the light above the bottle, then towards the side, and finally below it. He noticed the mixture had changed colors slightly at the different angles. He saw a faint blue, then red, and then orange. I asked him why he thought the colors were changing. He assumed that it had something to do with the milk, I said yes. I asked him if he knew that light was made up of many colors. He replied by telling me that he heard that on T.V.

I explained that the milk helped bring out the change in colors when the light hit it. He thought that was cool and told me about how he made “color fusion” - as he calls it -- something he discovered on his own. He can change the color of water just by adding a tissue, which had been colored with markers, into the water. The color dissolved right in.

About Betty Diop

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