## Thursday, April 28, 2011

### "Independent" Research Projects

BOAT: We chose the project to do the clay boats and hot air balloons. They float because of the density of air and buoyancy to float on the water. Buoyancy is the force equal to fluid...the weight of the displaced fluid. It is the upward force and keeps things floating. An object will float if the buoyancy is greater then the weight. We found the weight of the displaced fluid. We placed the boat in a container filled to the very top with water and formed a meniscus. When the boat was placed in the water, water spilled into a larger container and the this was the water the boat pushed out. Our little boat was 67.17 grams and the water it pushed out should have been equal to the boat. The water pushed out was 70 grams.

BALLOON:Denisty is: Mass/Volume Denisty is a physical property of matter that expresses a relationship of mass to volume. The denser, of two equal volume objects will be heavier. We made a hot air balloon with tissue paper, glue, templates and paper clips. We followed all the directions and created a balloon. We used the Indoor Balloon Tester and the pressure of the air pushing the balloon up made it float.

ARCHIMEDES: Archimedes Principle states:An object immersed in a fluid is buoyed up up by a force equal to the weight of the fluid displaced by the object. Knowing mass and volume of an object allows to calculate density.

1. so why did the boat push out 70 grams when the boat only had mass of 67 (conjecture)

weight of the balloon?? how much buoyant force?..how is this created?

calculation of density

anything interesting about Archimedes & density/buoyancy

2. The boat pushed out 70 grams of water when the boat was only 67 grams because the weight of the boat being placed in the water pushed out a couple extra grams of water. The boat was heavier so the boat pushed down when it was first released into the water. There was a lot of buoyancy in the hot air balloon experiment because buoyancy allows things to float. Without buoyancy, the balloon would not have floated. This was created with the hot air because hot air is more dense then cool air. The calculation of density is mass/volume. Archimedes lived on an island in Sicily.

3. I think Becca tried her best and tried to gain the most knowledge about it as she could. She thoroughly described the information in detail to where i could understand. She gets an A in my boook.

4. Becca gets an A in my book because she thoroughly descirbed the informaton and understoood what she was talking about.

5. I think becca did a great job about teaching me about buoyancy. Id give her a solid A

6. i think becca did very well on presenting buoyancy :) great A work!

7. next time lets us teach someone NOT in our group doing the same topic....

8. pictures???
video???