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Result
1 Watt = 1.3410e-3 Horsepower
Convert between watts, horsepower, BTU, and other power units used in engineering and industry.
| Watt (W) | Horsepower (hp) |
|---|---|
| 1 W | 1.3410e-3 hp |
| 2 W | 2.6820e-3 hp |
| 5 W | 6.7051e-3 hp |
| 10 W | 0.01341022 hp |
| 25 W | 0.03352555 hp |
| 50 W | 0.06705109 hp |
| 100 W | 0.13410219 hp |
| 250 W | 0.33525546 hp |
| 500 W | 0.67051093 hp |
| 1000 W | 1.34102186 hp |
Formula
Horsepower = Watt × 1.3410e-3
Worked Example
Example: 5 Watt = 5 × 1.3410e-3 = 6.7051e-3 Horsepower
To convert Watt to Horsepower, multiply the Watt value by 1.3410e-3. This factor is derived from the ratio between the two units.
The watt is the SI unit of power, defined as one joule per second. It measures the rate of energy transfer or conversion. Watts are used universally for measuring electrical power, light output, and heat generation.
History
The watt is named after Scottish engineer James Watt, who made significant improvements to the steam engine. It was adopted as the SI unit of power in 1882 by the Second Congress of the British Association for the Advancement of Science.
Horsepower is a unit of power used primarily to measure the output of engines and motors. One mechanical horsepower equals approximately 745.7 watts. It is the standard unit for expressing car engine power in the United States and several other countries.
History
Horsepower was defined by James Watt in the late 18th century to compare the output of his steam engines with draft horses. He determined that a horse could do 33,000 foot-pounds of work per minute, which became the definition of one horsepower.
Calculated using the latest NIST standards for physical constants and unit ratios.
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