Work and power calculator (physics)
Calculate the work of a force (W = F·d) and the power (P = W/t), in joules, watts and hp.
Assumes the force is in the direction of motion. 1 watt = 1 joule per second; 1 hp ≈ 735.5 W.
How the calculation works
Work is force times displacement: W = F · d, in joules. Power is work done per unit of time: P = W ÷ t, in watts. The faster you do the same work, the higher the power.
Examples
- Pushing with 50 N over 4 m: W = 50 × 4 = 200 J.
- Doing that 200 J in 5 s: P = 200 ÷ 5 = 40 W.
Frequently asked questions
Does holding a weight still do work?
In physics, no: with no displacement (d = 0), the work is zero, however tiring it feels.
Work vs power?
Work is the energy transferred (joules); power is how fast (watts = joules per second).
What is 1 horsepower?
A unit of power: 1 metric hp ≈ 735 W (US hp ≈ 746 W). Common for engines.
Does holding a weight still do work?
No. In physics, work requires displacement along the force. Holding still does zero mechanical work.
Work versus power?
Work is the energy transferred; power is how fast it happens.
Are cv and hp the same?
No. Metric horsepower is about 735.5 W and imperial hp about 745.7 W.
Does higher power mean more energy used?
Not necessarily — it depends on runtime. Power is the rate; energy is the total.
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Updated on June 30, 2026 · by Rafael Rossi · Methodology & sources