what is horsepower?
The engineer James Watt invented the term horsepower. Watt lived from 1736 to 1819 and is most famous for his work on improving the performance of steam engines. The story goes that Watt was working with ponies lifting coal at a coal mine, and he wanted a way to talk about the power available from one of these animals. In Watt’s judgment, one horse can do 33,000 foot-pounds of work every minute. So, imagine a horse raising coal out of a coal mine. A horse exerting 1 horsepower can raise 330 pounds of coal 100 feet in a minute, or 33 pounds of coal 1,000 feet in one minute, or 1,000 pounds 33 feet in one minute. You can make up whatever combination of feet and pounds you like — as long as the product is 33,000 in one minute and you have a horsepower. Using all of this information, you can begin to see that there are lots of different ways to make an engine perform better. Car manufacturers are constantly playing with all of the following variables to make an engine more powerful and/or
How do you define horsepower? Ask a car enthusiast and most of the time you’ll get a blank look, a shrug of the shoulders and maybe a guess along the lines of “What a horse can do!”. That answer begs the question: What horse? A thoroghbred race horse that can carry the small weight of a jockey with a lot of speed, or a working horse that can pull heavy loads albeit slowly? Obviously there is a more precise answer. Car manufacturers, despite their reputation for being creative regarding the horsepower ratings of their products for marketing reasons, require a more stable definition. Horsepower is defined as work done over time. The exact definition of one horsepower is 33,000 lb.ft./minute. Put another way, if you were to lift 33,000 pounds one foot over a period of one minute, you would have been working at the rate of one horsepower. In this case, you’d have expended one horsepower-minute of energy. Even more interesting is how the definition came to be. It was originated by James Wat
Horsepower is a unit of work established by James Watt who lived until 1819. Watt wanted to measure the amount of energy required to raise coal out of a coal mine and so he created ‘horsepower’ as the unit of measure. How much is one horsepower? One horsepower is equivalent to 33,000 foot-pounds of work performed in one minute. To give you a better sense of one horsepower, we have provided a list of equivalences – one horsepower equals all of the following: • lifting 33,000 pounds, 1 foot in one minute • lifting 1 pound, 33,000 feet in one minute • lifting 1000 pounds, 33 feet in one minute • lifting 1000 pounds, 330 feet in ten minutes • lifting 100 pounds, 33 feet in 6 seconds Watt used the term ‘horsepower’, because he estimated that this captured the amount of work an strong horse could perform. Horsepower has survived to this day as a way of expressing the power harnessed by automobiles and other engine-driven machines such as tractors and garden equipment. Modern cars typically h
