Hobbies And Interests
Blowing Ballast
This fluid statics activity demonstrates how ballast tanks in submarines and submersibles affect their buoyancy. You'll need a balloon, a large empty plastic soda bottle, a rubber band, fishing weights, a rubber hose, some tape and an aquarium. With the rubber band, tie the mouth of the balloon securely to one end of the hose. Place the balloon inside the soda bottle, and fill the bottle up with water. Next, fill the aquarium with water. Put the bottle in the aquarium and wait for it to sink. You can add weights to the bottle to hold it down. Observe what happens when you blow air into the balloon, and when you release air from it.
Spoon Candy
This spoon candy demonstration offers a clear look at simple fluid flow principles. All it requires is some spoon candy, a deep baking tray and a handful of peanuts or small, round candies. Make the spoon candy by combining 2 cups sugar, 1 cup butter, 3/4 cup light corn syrup and 2 cups table cream, stirring constantly until the mixture reaches 230 to 245 degrees Fahrenheit. Once the mixture reaches its soft-ball stage, pour the candy evenly into a baking tray. Place a row of peanuts or round candies along one edge, and raise that edge slightly. Prop the edge against something sturdy. Plot the gradual progression of the peanuts or candy throughout the day.
Paper Airplanes
This activity gives students the license to make and test as many paper airplanes as they can, while showing them first-hand how fluid dynamics works. The object is to design a paper aircraft that would stay airborne for the longest period. Students can have their pick of paper, folding pattern and size when conceptualizing their designs. Discuss how they can use Archimedes' Principle, Bernoulli's Principle, and air resistance to their advantage. All these principles are involved in fluid mechanics.
Floating and Falling Flows
This is another fluid dynamics activity which can illustrate the behavior of density- and buoyancy-driven flows. You'll need two tall glass containers filled with water for this activity. For your floating flow, mix around 16 1/2 ounces of isopropyl alcohol with a few drops of green food coloring in a paper or plastic cup. For the falling flow, your mixture will consist of 32 1/2 ounces of corn syrup combined with red food coloring. You'll also need two needless syringes with about four inches of thin tubing (or a stiff drinking straw) attached to the tip end. Fill one syringe with the green mixture, and the other with the red. Discharge the colored liquids into the water in the glass containers at roughly the same height. Observe how the colored blobs rise or fall.