What is the difference between power and energy?

Energy is the total amount of work done, while power is the rate at which that work is done. A 100 W bulb uses 100 joules of energy every second.

How do you convert watts to horsepower?

Divide watts by 745.7 to get mechanical horsepower. For example, 746 W is approximately 1 hp.

What is a kilowatt-hour?

A kilowatt-hour (kWh) is a unit of energy equal to 1000 watts sustained for one hour, or 3,600,000 joules.

Free Power (Physics) Calculator

Calculate mechanical power from work done and time using P = W / t.

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Work Done

Time

Power

200.00 W

Power (kW)0.2000 kW

Power (hp)0.2682 hp

Power vs Time

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Mechanical Power

Power is the rate at which work is performed or energy is transferred.

Formula

P = W / t

One watt equals one joule per second. To convert watts to horsepower, divide by 745.7.

Example Calculation

A motor does 1000 J of work in 5 seconds.

01P = W / t
02P = 1000 / 5
03P = 200 W
04P = 0.2 kW
05P = 200 / 745.7 = 0.268 hp

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