DRAFTING FOR SPEED N O I T C U D O R T N I Engines roar as race cars speed around the track With a track that is miles long there’s plenty of space for the cars to race Yet cars pair up racing one right in front of the other Why Whizzing around the track in tandem makes both cars move faster 4
The race car pairs are drafting When drafting billions of air molecules hit the car in front creating high pressure there The air pushes on the car before rolling across its top toward its rear Low pressure is created at the back of the car which slows the car down When two cars draft the air flow is directed over both cars as if they were one car The first car breaks through high pressure air but is not slowed down by low pressure at its rear The second deals with low pressure at the back but does not have to break through high pressure air at its front So both cars get a boost of speed
FORCES AND MOTION Motion is energy in the form of movement It’s easy to see the motion of race cars They whip around the track at super fast speeds But for a race to begin the cars need to get going Force is needed to set objects in motion Engines provide this force in race cars Force can also increase an object’s speed As the object moves it pushes back equally against the force On a race track the force of air pushes on the cars affecting their motion and speed The force of the car’s weight affects how well its tires grip the asphalt Studying forces and motion helps car designers build safer race cars And mastering the effects of different forces helps drivers reach top speeds 1 R E T P A H C 6
MEASURE IT MEASURING MOTION ANTELOPE 60 MILES PER HOUR 97 KMH SAILFISH 68 MILES PER HOUR 109 KMH FRED ROMPELBERG FASTEST BICYCLING RECORD 166 9 MILES PER HOUR 268 6 KMH PEREGRINE FALCON 200 MILES PER HOUR 322 KMH HENNESSEY VENOM GT SPORTS CAR 270 MILES PER HOUR 435 KMH LOCKHEED SR-71 SPY PLANE 2,193 MILES PER HOUR 3,529 KMH 100 200 300 400 500 600 MILES PER HOUR MPH Racing is all about speed An object’s speed is found by dividing the distance it covered by the time it took to travel The speed of a race car is measured in miles or kilometers per hour This graph shows some of the top speeds found in our world 7
