Case 1
- Work
- 1000J
- Time
- 10s
100.000W
Open with these valuesPower Calculator (Work ÷ Time)
100.000W
Result: 100.000 WWork divided by time. One watt is exactly one joule per second, so 1000 J spread over 10 s is 100 W. Power is a rate, not an amount: the same job done in half the time needs twice the power, while the energy bill stays the same.
Worked examples
Case 2
- Work
- 60J
- Time
- 2s
30.000W
Open with these valuesCase 3
- Work
- 500J
- Time
- 5s
100.000W
Open with these valuesHow it's calculated
P = work ÷ time
- StepEnter the work done, in joules.
- StepEnter how long it took, in seconds.
- ResultRead the power in watts; divide by about 745.7 for horsepower.
Reference table
| Work, time | Reading | Power (W) |
|---|---|---|
| 0, 5 | Nothing moved, no work done | 0 |
| 60, 2 | Thirty joules every second | 30 |
| 100, 1 | One hundred joules in one second | 100 |
| 500, 5 | Same rate, five times the job | 100 |
| 1000, 10 | Same rate again, ten times the job | 100 |
Questions
How do I calculate power?
Divide the work (energy) by the time: power = work ÷ time. For 1000 joules of work done in 10 seconds, that is 1000 ÷ 10 = 100 watts. Keep work in joules and time in seconds to get the result in watts (W).
What units does the power calculator use?
Work in joules (J), time in seconds (s), and power in watts (W). One watt is exactly one joule per second (1 W = 1 J/s).
What does power actually mean?
Power is the rate of doing work — how fast energy is transferred, not how much. Two engines can do the same total work, but the one that finishes faster delivers more power. A 100 W light bulb uses 100 joules of energy every single second.
What is the difference between power and energy?
Energy (work) is the total transferred, measured in joules; power is the rate of that transfer, measured in watts. Multiply power by time and you get back the energy: 100 W for 10 s is 1000 J. So a high-power device is not necessarily energy-hungry — it just delivers its energy quickly.
How do I convert watts to horsepower?
Divide the watts by about 745.7, the number of watts in one mechanical horsepower (550 foot-pounds per second). So 100 W is roughly 0.134 hp, and a 745.7 W motor is about 1 hp.
Where is the power formula used?
Everywhere energy moves over time: rating engines and motors, sizing appliances (a kettle might draw 2000 W), measuring exercise output on a bike or rowing machine, and reading electricity bills (a 100 W device left on for 10 hours uses 1 kWh).
Sources and last check
Information, not professional advice.