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ZOOM™ ZOOMsci: Science rocks! |
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Soap-Powered Boat II next ZOOMsci | ZOOMsci index | list of activities | Your Results Sent in by: Lauren and Emily of Orange City, IA Soap up for speed! Materials needed:
Instructions: 1. Check with an adult before you begin. You'll need a place to experiment with your boats like the bathtub or an inflatable wading pool. Make sure it's okay to fill up the tub or wading pool before you get started. 2. To make a boat, glue two plates together face to face so that their top edges meet. 3. Glue the bowl upside down on top of one of the plates. 4. Poke a hole near the bottom of the cup and glue the bottom of the cup to the bottom of the bowl. 5. Put the short end of the bendy straw through the hole in the cup. The other end of the straw should point down. 6. Make two boats. When the glue dries, decorate your boats with paints or markers. 7. To make your boat move, just set it on the water, pour water into the cup and watch it go. 8. Now here's where things get sudsy. In the ZOOMphenom, Soap Power Boat, you can make an index card boat move through water using only liquid dishwashing soap. If soap makes that boat go, won't it make your water-powered boat go faster? To try it out, mix some liquid dishwashing soap with water and pour it into the cup on top of one boat. Pour plain water into the cup on the other boat. 9. Race the water-powered boat with the soapy-water-powered boat. Then write to ZOOM with your race results. Did one boat go faster than the other? Why do you think it did or didn't? What other liquids might affect the speed of your boats? Try powering a boat with fizzy water, sugar water or any other kind of liquid you can think of. Then write to ZOOM and let us know what you've discovered. Lathered-up for the science scoop? When you put water into a cup without a hole, the water pushes on the cup in all directions. When you put a hole in the cup, part of the cup is missing, so the water can no longer push there. But the water is still pushing on the other parts of the cup. That's what moves the cup and the boat along. What's all the suds about soap, you ask? The attraction between water particles at the water's surface produces surface tension. This gives the surface a skin-like quality. Think of this thin, skin-like quality like a balloon. Adding liquid soap is like popping the balloon. You break the surface tension; the thin "skin" breaks and pulls away to the sides. If there's something floating on these water particles, like the boat, it goes along for the ride. You can also send us your pictures or video of this ZOOMsci: ZOOMsci ZOOM Box 350 Boston, MA 02134 Some of your results: ZOOM wrote: This is new! ZOOM wrote: We need your comments! ZOOM wrote: Send it to ZOOM!
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