This second part, continues from the May issue. It includes surface temperature effect on speed, and his answers to specific questions. The color of a derby car's surface determines how much solar heat it will absorb, and in return, radiate to the wheels, increasing your racers speed. A white surface will absorb very little solar energy, about ten percent. However, a black surface can absorb almost 95 percent.
Radiated heat is radiated in straight lines.
It is also radiated in all directions from any point. The larger the radiating source the more heat will be transferred. A black body will radiate the maximum possible energy at all wavelengths. The ambient air temperature was 77 degrees. The racer's surface temperature reached 172 degrees, and the wheel 156 .