Introduction
A vortex is a spiral motion of fluid that sucks everything near it towards the center. These “center pulling” forces are made by a combination of air pressure, water pressure and gravity. As the water starts to spin, it pushes out against the bottle and leaves a hole in the middle. The hole in the middle allows the air in the bottom bottle to travel upward. As the air comes up, the water can flow into the bottom bottle because there is now space for it to move. The water dropping through an opening is called a vortex. Visit the Children's Museum of Houston to see a giant vortex in the
FlowWorks exhibit!
Materials
- Paintbrush
- Two Empty Plastic Soda Bottles (same size)
- Duct Tape
- Water
- Food Coloring or Glitter (optional)
Procedure
- Fill one bottle ¾ full of water.
- Add food coloring or glitter if desired.
- Tape the empty bottle to the top of the other bottle. Line the spouts up and tape securely.
- Turn the bottles over so that the one with water is on top. Place your hands at the top of the bottle and gently, but quickly, rotate the bottles in tight circles. (Don’t shake it up and down - just swirl.)
- Set the bottles back on the table and watch.
Questions to Ask
- What do you see? Does the water empty easily into the other bottle?
- What is happening to the water inside the bottles?
- What happens if you turn the bottles in the other direction?
- Can you describe the way the water moves? Use words and phrases like, “straight line, zigzag, up and down, back and forth, round and round, and fast and slow.” Can you demonstrate these motions with your hands?
- What does this experiment remind you of in the real world? What scientist would need to understand this science concept? Why?
- When you added glitter to the water, did you change the water’s physical property? Why or why not?
- How could you communicate observations with your peers?
- How could you record your observations?
Exhibits: | How Does It Work?Invention ConventionMatter Factory |
Subjects: | Physical Science |