```Okay so I was playing a bit fast and lose. :-) Seems most got my point however. At least I know you guys do read my posts. :-) Gary McCormick wrote: > > I think what Marc /meant/ to say was KE = 1/2 (Iw^2), where KE is the >kinetic energy of > the rotating mass, I is the moment of inertia and w is the angular velocity >(^2 means > squared). > > What this equation tells us is that increasing either the moment of inertia >of the > flywheel or it's angular velocity (rpm) will increase the amount of stored >energy it > represents. One can also see that it takes more energy input to raise the >angular > velocity to a given value if the value of I is higher. I is representative >of not only > the mass, but its distribution, and as Marc stated in the full text of his >post, mass that > is located further from the rotational center of the flywheel resists >rotation more than > the same mass closer to the center (or words to that effect), in addition to >the thermal > issues to be considered. > > Isn't physic fun? > > Gary McCormick > San Jose, CA > > Marc Sayer wrote: > > > The energy from the rotation of the flywheel (e=MC2) is added to the >torque > > produced by the engine to help overcome the inertia of the vehicle and get >it > > moving. You can compensate for a reduction in that rotational inertia >caused by > > a reduction in mass, by simply raising the engine speed (a reduction in M >can be > > offset by a corresponding increase in C). -- Marc Sayer 82 280ZXT 71 510 2.5 Trans Am vintage racer ```