Mechanical power is also described as the time derivative of work. In mechanics, the work done by a force F on an object that travels along a curve C is given by the line integral : W C = ∫ ∫ C F ⋅ ⋅ v d t = ∫ ∫ C F ⋅ ⋅ d x , where x defines the path C and v is the velocity along this path.