----- Original Message ----- From: Terry Blanton <[email protected]> Date: Friday, February 6, 2009 9:39 am Subject: [Vo]:Time Variant and Invariant Forces: Steorn's Error?
> I posted at Steorn: > > http://www.steorn.com/forum/comments.php?DiscussionID=61501&page=1#Item_1 > > The energy required to lift a bucket results from applying a force > over a distance. The amount of energy required is not a function of > time. Whether the bucket is lifted in minutes or hours, the energy > expended is the same for a given distance. Gravity is a time invariant > force. Well that is what the math indicates, but I have suggested before that gravity or, more precisely, WEIGHT is a "time varying" force. In Newtonian gravity weight W is a function of mass m, and gravitational acceleration g. Without specifying the precise relationship one may write this functional relationship as W = f(m,g) My suggestion is that weight is a function of mass m, gravitational acceleration g, and velocity v: W = f(v,m,g) If *weight* decreases with velocity it would matter how quickly the bucket was lifted a given distance because it would reduce the energy required. harry
