Water Bottle Rocket Design Seminar on Saturday, October 30th from 9 AM to 1 PM, at Discovery Key Elementary, 3550 Lyons Rd., Lake Worth, FL. Students are responsible for their own transportation to and from the seminar.
Directions: I-95 to 10th Ave. N. Go west to Jog Rd. South on Jog to Lake Worth Rd. West on Lake Worth Rd. to Lyons Rd. North on Lyons. School is on the right--past entrance to Cypress Woods development.
Excerpt from the Water Rocket Construction
Working in teams, students construct a simple bottle rocket from two-liter soft drink bottles and other materials. The rocket is powered by air pressure and water.
A water rocket is a chamber, usually a 2-liter soft drink bottle, partially filled with water. Air is forced inside with a pump. When the rocket is released, the pressurized air forces water out the nozzle (pour spout). The bottle launches itself in the opposite direction. The bottle usually has a nose cone for streamlining and fins for stability. Water rockets are easily capable of 100-meter-high flights, but advanced hobbyists have combined bottles and staged bottles for flights over 300 meters high.
Water bottle rockets are ideal for teaching Newton’s laws of motion. The launch of the rocket easily demonstrates Newton’s third law. Students can see the water shooting out of the nozzle (action) and see the rocket streak into the sky (reaction). Students can also experiment with different pressure levels inside the chamber and different amounts of water. The rocket will not fly very high if it is filled only with air. The air will quickly rush out during the launch, but its mass is very low. Consequently, the thrust produced is also low (Newton’s second law). By placing water in the bottle, the air has to force the water out first before it can leave the bottle. The water increases the mass expelled by the rocket, thereby increasing the thrust.
Like all rockets, the flight performance of water bottle rockets is strongly influenced by the rocket’s design and the care taken in its construction. Beveling the leading and trailing edges of fins allows them to slice through the air more cleanly. Straight-mounted fins produce little friction or drag with the air. A small amount of ballast weight inside the nose cone helps balance the rocket. This moves the center of mass of the rocket forward while still leaving a large fin surface area at the rear.
