Work (Physics) Calculator
Compute work W = F·d·cos(θ). Force in N, displacement in m, angle in degrees.
W = — J
Work in physics: W = F·d·cos(θ)
Work measures the energy transferred by a force acting on a body that undergoes a displacement: W = F·d·cos(θ), where θ is the angle between force and displacement. The unit is the joule (J = N·m). Work is zero when F ⊥ d (centripetal force does no work) and negative when θ > 90° (friction, brakes). The work-energy theorem states that W_total = ΔEc. Conservative forces (gravity, elastic) yield work independent of the path; non-conservative forces (friction) depend on the trajectory. Example: pushing a 50 N box for 10 m horizontally gives W = 500 J; if the force is at 30° to the motion, W ≈ 433 J.
Applications
Strength training quantifies work as the load lifted times the height. Mechanical efficiency η = W_useful / W_total describes engines: gasoline ~25%, diesel ~40%, electric ~90%. In thermodynamics, work appears in the first law (ΔU = Q − W) and drives heat engines and refrigerators.
FAQ
Why is work zero when carrying a box at constant height? Because the lifting force is vertical and the displacement is horizontal — θ = 90°, cos(θ) = 0.
What's the difference between work and energy? Energy is a state (stored capacity); work is the process of transferring energy. Work changes the energy of a system.
Can work be negative? Yes — friction, air drag, and brakes all do negative work, removing kinetic energy from the body.
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The results provided by this tool are for general informational and educational purposes only and do not constitute professional, financial, medical, legal, tax or accounting advice. Always confirm important decisions with a qualified professional and official sources.