At a Glance: Students design and build a race car, perfecting their design in a wind tunnel as they go. The activity culminates in an exciting drag racing competition where cars speed down a 65-foot track powered by gas escaping from an onboard CO2 cartridge.
Concepts: Students strive to optimize their car's aerodynamic efficiency, rolling resistance, and weight while working within a set of tolerances. Newton's third law is another important concept illustrated by this activity.
Details:
After viewing an informative lesson on the physics that govern dragster performance and observing the pros and cons of various dragster body types, students design and create a working drawing of a CO2 dragster. Using the drawing as a pattern, they cut a prototype of their design from a Styrofoam™ block with a Styrofoam saw or a hot-wire cutter and sand it smooth with 320-grit sandpaper. After examining the prototype for weaknesses, they modify the design if necessary to reduce weight, eliminate fragility, or increase aerodynamic efficiency.
Next, using their revised drawing as a pattern, students construct the actual dragster from balsa or basswood using either hand tools (such as a drill, rasp, saw, and wood carver's tool) or power tools (such as a scroll saw, drill press, and Dremel tool). The dragsters are sanded and then finished with sanding sealer, spray or acrylic paint, and decals. Axles and wheels are attached and the vehicles are wind-tunnel and roll-ramp tested. Results are recorded and used to predict the dragster's racing performance and improve future designs. Finally, dragsters are launched and timed on a race track using Pitsco's i-race, a racing system designed to work with your Macintosh or PC to automatically launch two CO2 dragsters simultaneously, detect when each passes through the finish gate, and instantly record their racing speeds.
At a Glance: Students design and build a race car, perfecting their design in a wind tunnel as they go. The activity culminates in an exciting drag racing competition where cars speed down a 65-foot track powered by gas escaping from an onboard CO2 cartridge. 
