What is horsepower units

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That amount of work equals one horsepower. Watt used his newly invented unit of power to compare how much work his stationary steam engine could do with that of a horse. It was the just marketing magic he needed to convince companies that the newfangled technology was the better power source.

That breakthrough, as we all know, revolutionized both industry and transportation, and would eventually lead to the rise of steam ships and locomotives. And it's also why buyers of everything from muscle cars to lawn mowers owe a debt of gratitude to James Watt.

Users of lightbulbs too. Engineers posthumously honored Watt by naming a unit of power after him, the watt. Ironically, one "watt," doesn't equal one horsepower. Therefore the term "horsepower" may seem slightly misleading, but Watt did have his reasons for such a name. When Watt made his improvements to the steam engine, he understandably wanted to convince people to buy it. If he said that his expensive engine had the same short-term output as a horse, people wouldn't buy it, as they already had horses.

Instead, he compared it to the amount of work a horse could do in a day, giving it the output of ten horses instead of just one. Suddenly his invention became much more tempting. Although Watt may have "bent the truth" to make his engine more appealing, he was not lying. While it is true that the maximum output of a horse is around 15 horsepower, when you average the output of a horse over the course of a work day it ends up being around a horsepower.

Watt defined this amount as "the amount of work required from a horse to pull pounds out of a hole that was feet deep". James Watt chose to compare his engine, which was capable of sustaining it's power output for a full day, to a horse's average power output over a day.

To further complicate matters, European and Japanese car manufacturers use a metric measurement of horsepower.

One metric horsepower is slightly more than one brake-horsepower. Why the difference? Well, on the part of the car magazines, old habits die hard. There was a time when the kilowatt was the preferred measure. The higher the number of kilowatts the more powerful the batteries.

You might be wondering where torque comes into all this. In simple terms, torque is a different measurement of the work an engine can do, taken from a different part of the engine. The ideal is an engine with lots of both. Think of the difference between power and torque as the difference between an explosion and a fire.