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Strategies & Market Trends : MDA - Market Direction Analysis

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To: Webster Groves who wrote (73842)	4/2/2001 11:22:28 AM
From: ahhaha	Read Replies (1) of 99985

You are some kind of engineer. Don't swim in a physicist's soup. F=ma is currently a fact (a theory "proven" by experiment). How does one measure "F"? It isn't possible since F = ma is true by definition. "a" isn't measurable either. We get a handle on it by inference from a = dp/dt. We can measure p. Don't let ahahaha's technobabble influence you. He has the jargon but not the construction to say it correctly. Is the below your "construction"? I wonder what you're trying to show? Special and General relativity simply redefine the coordinate systems for certain conditions. Einstein would be very disappointed by this statement. It misses the crucial point of Relativity. The above is what we call a scalar, vector or tensor theory of gravity. They all fail under measurement. Einstein said in 1913 that he had to do exceedingly difficult calculations to go beyond the limitations of mere coordinate invariance. It forced him to the wild conclusion that space was curved. F = F(up) + F(down) Why rockets go up ? F(up) = v dm/dt (stuff shoots out the back) Why rockets do down ? F(down) = Mg (g is gravity and says so). This isn't germane to any comment that went before. Your "m" above is merely m = m1 + m2, where m1 is rocket mass before and m2 is rocket mass after. At an instant not one atom has left the rocket. dm/dt = 0. When the rocket has achieved orbit, F = 0. If not, the rocket would break orbit. So either v = 0 or dm/dt = 0. v isn't zero. F = 0, F(up) = 0, but F(down) isn't zero, because the rocket still has mass and the gravitational constant is still non zero. The rocket's velocity is compensating for earth's gravity by changing direction. None of this is germane. The previous comments dealt with whether the mass of the rocket in orbit, in compensated g, or zero g, changes as a function of velocity. You seem to have missed Galileo in your hasty physics. What we'd like to know is whether mg = ma. Is the Equivalence Principle true? Eotvos seemed to think so, but there are doubts.

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