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High-Tech Channel Hitachi High-Tech GLOBAL

Work rate of horses studied by Watt

Symbol: HP, ㏋, PS / Base data: Rate of production, workrate.
1 French horse-power (PS) = 735.5W

French horse-power is used in Japan

James Watt came up with the idea of comparing the power of steam engines and horses. 1 horsepower is calculated as carrying 550 pounds for 1 foot in 1 second, which is British horse-power. In Japan, the French horse-power that is determined by the metric system is permitted to be used, but there are times when it is not accepted.