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Gravity-Powered Car

The National Highway Traffic Safety Administration (NHTSA) is an integral part of the United States Department of Transportation (DOT) and its mission is to save lives, prevent injuries, and reduce traffic-related health care and other economic costs associated with motor vehicle use and highway travel. To accomplish this, NHTSA collects and analyzes motor vehicle crash data, and develops, promotes, and implements educational programs, vehicle safety standards, research, and enforcement programs. In 1979, NHTSA created the New Car Assessment Program (NCAP) to improve occupant safety by developing and implementing meaningful and timely comparative safety information that encourages manufacturers. | Gravity-Powered Car Challenge Design and build a model car that can roll as far as possible across a floor propelled solely by rolling down an inclined ramp. Overview Although conceptually simple gravity-powered cars are engaging projects. Students enjoy making and testing them and they learn the construction techniques required for the more complex vehicles that follow. Gravity-powered cars are ideal for teaching the methods of science which include independent research data collection graphing and interpretation of graphs and data. I suggest specific materials to use but a wide variety of materials some free and most inexpensive will work. Materials Cardboard 1 large box or 2 small boxes Fat straws 1-2 per team 1 dowels budget 8 per team Wooden wheels 4 per team or plastic wheels with 1 8 dowels and regular straw Hot glue or masking tape Sandpaper or sanding blocks 1 per two teams Inclined ramp Meter sticks 2-3 CDs make great plastic wheels if you have plastic inserts to fit inside the center hole. The inserts fit a 1 4-inch dowel. Since these are much larger than the other wheels cars using them can roll easily. The Web site www.Kelvin.com sells plastic inserts and your postal carrier probably delivers free CDs such as those offering Internet services. A pine board with one-inch by four-inch sideboards to keep cars from falling off the edge makes a great ramp. To reduce the gap between the ramp and floor plane or rasp wood off the bottom edge of the ramp. Cardboard reinforced with strips of cardboard also works. Prop up one end of the ramp with a chair or table and secure it with duct tape to prevent movement. Design Concept Attach sections of straw to the bottom of the chassis made from a rectangular piece of cardboard . Run dowels through the straws and outfit the dowels with two wheels each. Students can also try the more challenging design of three-wheeled cars. 10 GRAVITY-POWERED CAR 11 The Details Ask students to choose their own teams each with a maximum