This week we will do several experiments, but our main focus is going to be the process of science instead of the science behind the experiments.
To try this, you will need:
- a drinking glass
- water
- a variety of materials from around your house
- lots of imagination
The challenge is to take a glass of water and turn it upside down, without spilling the water. If you have read many books of science experiments, then you have probably heard that you can place a sheet of cardboard over the glass and turn it upside down. You can then release the cardboard, and it will stay in place. The card is held in place by air pressure. OK, so the experiment is over, right? No. Most of us are trained from a young age to look for the right answer and then stop, but a good scientist keeps looking for more answers. That is because many problems have more than one answer. For example, there are other ways you could keep the water in the cup. For example, you could:
1. Freeze the water.
2. Solidify it chemically. You can do this with a chemical like sodium polyacrylate, which is found in disposable diapers. You could also do it by adding gelatin to the water. Just follow the directions on the package.
3. Soak the water up in something. Simply stuff some paper towels into the glass. The paper absorbs the water and holds it in.
4. Put it under water. When you have the glass under the surface of the water, it will be filled. You can then turn it upside down, and it will still be full.
5. This is my favorite. Go outside. Trust me on this, as this way takes some practice and can make a mess. Put some water into the glass. Use a plastic or paper cup, not something made of glass. Hold it firmly at the top. Now, quickly swing your arm in a circle, going up over your head and then back to your side. At the top of the circle, the cup will be upside down, but the water will stay inside. Due to inertia, when you get the water moving, it tries to continue in a straight line. This forces the water towards the bottom of the cup, keeping it in, even when it is upside down.
6. Surface tension. Cover the top of the glass with some fine mesh window screen. Rub the screen with a little oil. Now pour water into the glass through the screen. It goes in just fine. Then place your hand over the screen to hold the water in while you turn it upside down (over the sink). When you remove your hand, the water stays in. The surface tension of the water holds it together. The combination of surface tension and air pressure keeps the water inside the cup.
7. Take it into orbit. In the microgravity of space (No, things are not weightless in space.), you would be able to turn the glass upside down and the water would stay in the glass.
Did you think of any ways that I missed? I am sure that there are more. Now that you have the idea, I am certain that some of you will put your brains to work and come up with more ways to accomplish the task. If you do think of other ways, please let me know.
I know that I have glossed over much of the science, but if you want to know more, you have a good start. A quick trip to the library or hitting your favorite Internet search engine will yield an incredible amount of information for you.
Have a wonder-filled week.
