Power Calculator

Understanding the Rate of Energy Transfer

Power is the rate at which work is done or energy is transferred. This calculator determines power (in Watts) by dividing the total work performed (in Joules) by the time it took to perform that work (in seconds). It's a key concept in physics and engineering.

The Power Formula Explained

The formula for power is: P = W / t

• P (Power): The rate of energy transfer, measured in Watts (W). One Watt is equal to one Joule per second.
• W (Work): The total work done or energy transferred, measured in Joules (J).
• t (Time): The time over which the work was done, measured in seconds (s).

How to Use the Calculator

1. Work (Joules): Enter the total amount of work done.
2. Time (seconds): Enter the time it took to do the work.
3. Calculate: The tool will display the calculated power in Watts.

Real-World Example

An engine does 10,000 Joules of work in 4 seconds.

• Work (W): 10,000 J
• Time (t): 4 s
• Calculation: Power = 10,000 J / 4 s = 2,500 W
• The engine has a power output of 2,500 Watts (or 2.5 kilowatts).

Frequently Asked Questions (FAQ)

• What's the difference between work and power? Work is the total amount of energy transferred. Power is how fast that energy is transferred. A person can do the same amount of work climbing a flight of stairs whether they walk or run, but they generate more power when they run because they do the work in less time.
• How does this relate to horsepower? Horsepower is another unit of power. One horsepower is approximately equal to 745.7 Watts. You can use our Power Converter to switch between these units.
• Can I calculate power from force and velocity? Yes. Since Work = Force × Distance and Power = Work / Time, you can combine them to get Power = (Force × Distance) / Time. Because Velocity = Distance / Time, the formula simplifies to Power = Force × Velocity.