The energy conservation equations for the MF are different than those for the TTD because the lift hill puts potential energy into the system. The empty car requires less potential energy (which is based on mass) than the fully laden one will. So the fully laden car will see more frictional forces, but it starts with more mass, so it has more kinetic energy at the bottom of the hill. It's unclear which car will actually be moving faster without a serious analysis of the frictional forces, which is a much more complicated problem :)
The Feather vs. Bowling ball issue isn't so much the mass as it is the wind resistance. Since the feather has so much more surface area compared to its mass, it will fall much slower (similar to a skydiver with his arms spread wide, vs. one with his arms tight to his body, falling straight like an arrow) two objects in a vacuum will fall at the same rate, regardless of their mass.
And before you guys ask, yes, I am a rocket scientist (I work at NASA Glenn in Cleveland)
And one more thing, while I'm on this science kick, I decided to figure out what the theoretical top speed of the TTD would be, starting from the top of the tower at 0 mph and accelerating straight down through a drop of 400 feet. Turns out it's about 110 mph. So add to that the 15mph that is the estimated speed over the tophat, and we're losing about 5 mph in frictional forces (both car to air and car to track) . Of course, if the estimated speed over the top hat is closer to 10mph, then the frictional forces are practically nil.
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Come on people, this poetry's not going to appreciate itself!
*** This post was edited by tremor 4/23/2003 10:07:00 AM ***
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