9781422274743

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CHAPTER

SPEED

Introduction Most likely, the first thing that comes to your mind when you think of auto racing is speed. In the sport, the driver, pit crew, and car design are all important; but the engine in particular may be the single most crucial component of a race. Why? The engine is key because it must create massive amounts of power for hours and hours without failing. Race engines in NASCAR, for instance, produce 750 or more horsepower , a term invented in the late 1700s by inventor and engineer James Watt, who is probably most famous for his improvements to steam engines. Watt also learned to convert horsepower into other measures, such as wattage (which is named for him), to show the power of light bulbs. Horsepower What is horsepower and how does it relate to engine performance? Watt worked with horses at a coalmine. The horses were harnessed and pulled ropes to lift buckets of coal out of the mine. Watt needed a way to quantify the lifting power provided by the horses. Watt collected data over many weeks and found that the average horse (1 horsepower) could raise 330 pounds out of the mine. The horse had to raise the bucket 100 feet and could do so in one minute.

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