Laura+McCaughey

Soap Box Derby is often referred to as “gravity powered” racing. Soap Box derby cars do not have a motor, therefore rely on gravity and other forces to get down the hill and across the finish line first. These cars have a steering wheel, brake, weights, and despite what people think, require skill when driving. There is also a weight requirement that must be met for each division. The cars in this image are super stock cars. The weight requirement for this division is 230 pounds including the driver.
 * Soap Box Derby**

Usually when the paddle drops and the car is released onto the hill, the driver will steer towards the cones and hold a straight line. Since the hill usually drops off towards the sidewalk, the best speed advantage will be gained when holding a straight line as close to the cones as possible. Before steering towards the cones, momentum must be picked up because it will allow the car to pick up speed before accelerating. The key point is to hold the steering wheel straight after an adjustment towards the cones is made. Avoid any little movements because this will create friction, which slows the car down. Gravity is acting on the car as it travels down hill. Gravity causes the car to accelerate. Although gravity aids in acceleration, the car must be as aerodynamic as possible to reduce the affect air resistance. One way to make the car as aerodynamic as possible is to have a low center of mass. If the center of mass is low, the car will move faster. To obtain a low center of mass, the weight must be distributed near the axles. Having a low center of mass creates potential energy that will ultimately increases inertia. The potential energy is then converted into kinetic energy as the car travels down the hill.

Overall, the way the car is built has a major impact on the success of the driver. The car is built using physics to achieve the fastest possible time. Although the car is strategically built, driving has a lot to do with the result of the race. If a person with a good car is racing another person whose car is not as good, the person with the better car may lose if they do not drive as well as the other person.

__**Physics Topic Categories:**__ Gravity- Friction- Center of Mass- Acceleration __Sources:__ Gale, Paul. "Physics Involved In Soap Box Derby Racing." //Marietta Soap Box// //Derby//. Zenith Design Group, Inc., 2011. Web. 19 Dec. 2011. .