It's the 21st century, why do people still use horse power to measure power?

Ever since, we are familiar with the calculation of power based on the horse's pulling power, but have never wondered about their accuracy.

Many modern car models today still use horsepower units to express the power of the engine. In fact, horsepower is still considered an important specification for buyers to consider and choose the right vehicle, as it is a parameter that directly affects the performance of the engine.

Picture 1 of It's the 21st century, why do people still use horse power to measure power?
Horsepower is a unit used to measure power.

Although the use of horse power in the 21st century is considered "outdated" by many, questions about horsepower such as how much horsepower a horse can produce, or how precise horsepower, remains something many people are interested in.

What is horsepower? Used since when?

Horsepower - or horse power (abbreviated as HP - Horse Power) is a unit used to measure power. It is defined as the work required to lift a 75 kg mass 1 meter high in 1 second or 1HP = 75 kgm/s.

To quickly convert between "horsepower" and "kW" (kilogram watts), the following relative factors are commonly used:

England: 1HP= 0.7457 KW

French:1 CV= 0.7455 KW

1Kw= 1.36CV = 1.34HP

According to the University of Calgary's Energy Education website, a horse's maximum output is actually closer to 15 hp. Meanwhile, the power from a normal healthy person can produce approximately 1 horsepower. Therefore, a more appropriate name for this unit might be "human power".

Horsepower was first mentioned in the late 1700s by James Watt, a Scottish engineer. He is also remembered for inventing the iconic steam engine and for making many contributions to the car industry. For recognition, his name was given to the power unit in 1882.

Back in the 1700s, while Watt was searching for a name that would effectively represent the superiority of steam engines, he came up with a unit of measure that referred to something most people didn't know. familiar at the time: horses.

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James Watt is the creator of the concept of "horsepower".

From personal observation rather than scientific research, Watt determined that a workhorse can spin the wheel an average of 144 times per hour. Using this number, he estimated that the horse was capable of pushing 32,572 pounds/foot per minute, or 14,774.41 kg/m. For added convenience, he rounded this up to 33,000 pounds (14,968.55 kg), and the "horsepower" unit was born.

At the time, Watt did not care much for the accuracy of the measurement, only knowing that it highlighted the dramatic productivity improvements of the steam engines he built.

As a result, these engines actually became much more powerful and reliable than horses, leading very few to question - or care about - the veracity of his calculations.

Horsepower units exist to this day, and no one seems to bother redefining them because they've become so commonplace.

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