Michel Jullian wrote: > > To Harry: I don't know of a special name for dP/dt, what would be your use for > the second derivative of energy wrt time?
I think the so-called natural forces should be reassessed in terms of power rather than force. The only natural power that is correctly assessed by force is inertia. Knowledge of inertia comes about through the exercise of force. However the knowledge of gravity, electricty and magnetism comes about through the observation of motion. Of course you can use them as forces, but that does not mean they ARE forces. So how does one quantify a natural power? Simply by an acceleration. Nothing is causing the acceleration except for the presence of another body. The other body isn't acting-at-a-distance or warping space-time. To resist gravity all you need is an opposing force, but a I said before, this does not mean gravity IS a force. It only means that it responds to a force. Moving upwards at a steady pace requires more than a force. It requires power. The speed of motion upwards determines how much power is used per second. This is dp/dt. This figure is not the total energy required to reach the summit. It is the energy required to keep ascending at a given speed. No one can be certain the climber will reach the summit, not even the climber. Harry
