Paul,
I think what you are alluding to is more correctly called "power" rather than "energy". Indeed, "power" can be defined without the concept of "energy". All you need to express power is force F times velocity v, *Dimensionally* this has the same units as [E]/[t], since [F][v] -> [m][a][v] -> [p]^2/[m][t] -> [m]^2[v]^2/[t] In first year physics the power needed to lift a weight is usually presented in terms of force f, the height it is lifted and the time taken( P = Fd/t = Work/t = E/t) This gives the _total_ power required, but the significance of the number lies in the design and completion of a task. This number might of interest to the person performing the task or to an energy planner but the machinations of men are simply incidental to nature. A quantity that is not incidental to nature is the instantaneous rate of power consumption. If the weight being lifted at time t has a velocity v, then the lifter (man, animal or machine) must have an instantaneous power consumption rate. Harry
