# How Horsepower is equal to 550 ft lb/s ?

• PHYSICS5502
In summary, horsepower is a unit of measurement that represents the amount of work an engine can do in a certain amount of time, with one horsepower being equal to 550 foot-pounds of work per second. Ft lb/s is a unit of measurement for work or torque, with one horsepower being equal to 550 foot-pounds per second. Horsepower is commonly used as a unit of measurement for engines due to its simplicity and standardization, and it was also a familiar unit when engines were first invented. However, horsepower is not the only factor that determines engine performance, as other factors such as torque, displacement, and efficiency also play a role. Horsepower can be converted to other units of power measurement, but the conversion rate varies depending
PHYSICS5502
How did James Watt found out that one horsepower is equal to 550 ft lb/s ? There must be some sort of derivation or something that he did.Can anyone show me that derivation.

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From observation of the haulage power of a horse . He fiddled the answer a lot though for commercial purposes .

Boulton and Watt manufactured steam engines .They were a bit notorious for making exaggerated claims about the power and economy of their engines compared to horses .

https://en.wikipedia.org/wiki/Horsepower#History_of_the_unit

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PHYSICS5502

## 1. How is horsepower defined?

Horsepower is a unit of measurement that represents the amount of work an engine can do in a certain amount of time. Specifically, one horsepower is equal to 550 foot-pounds of work per second.

## 2. What is ft lb/s and how does it relate to horsepower?

Ft lb/s stands for foot-pounds per second, which is a unit of measurement for work or torque. One horsepower is equal to 550 foot-pounds per second, meaning that an engine with 1 horsepower can do 550 foot-pounds of work in 1 second.

## 3. Why is horsepower used as a unit of measurement for engines?

Horsepower is commonly used as a unit of measurement for engines because it provides a simple and standardized way to compare the power output of different engines. It was also a familiar unit of measurement when engines were first invented, as it was often used to measure the power of horses.

## 4. Is horsepower the only factor that determines the performance of an engine?

No, horsepower is not the only factor that determines the performance of an engine. Other factors such as torque, engine displacement, and efficiency also play a role in the overall performance of an engine.

## 5. Can horsepower be converted to other units of power measurement?

Yes, horsepower can be converted to other units of power measurement such as watts, kilowatts, or British thermal units per hour. However, the conversion rate will differ depending on the specific unit of measurement being used.

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