Imperial/US

Horsepower

Definition

A unit of power. Mechanical horsepower equals approximately 745.7 watts.

Explanation

James Watt coined the term to compare steam engine output to draft horses. One hp was defined as the power to lift 33,000 pounds one foot per minute.

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RELATED CONVERSIONS

Horsepower (mechanical) → Watt Horsepower (mechanical) → Kilowatt Horsepower (mechanical) → Megawatt Horsepower (mechanical) → Gigawatt Horsepower (mechanical) → Horsepower (metric) Horsepower (mechanical) → BTU per Hour
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RELATED TERMS

Imperial System

A system of measurement used primarily in the United States, based on historical English units.

Troy Weight

A system of weights used for precious metals and gemstones.

Avoirdupois

The standard system of weights based on the 16-ounce pound, used for everyday goods.

BTU (British Thermal Unit)

The amount of heat needed to raise the temperature of one pound of water by one degree Fahrenheit.

PSI (Pounds per Square Inch)

A unit of pressure expressing force in pounds applied over one square inch.