Power loss
Also: dissipation, parasitic loss
Input power converted into an unintended form rather than useful output.
Loss depends on the chosen system boundary and may appear as heat, sound, vibration, slip, fluid drag, or electrical dissipation.
- Units
- watt (W)
- Formula
P_loss = P_in − P_useful
Example A gearbox taking 10 W and delivering 8 W loses 2 W.
Common misconception Lost useful power is transformed, not destroyed energy.