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A comment on MT-Propeller 11 blade propeller delivers 15% increase in static thrust. Parent comment

Re:MT-Propeller 11 blade propeller delivers 15% increase in ... by WalterBright on Friday January 06, 2023 @05:19PM (#34282093)
Please rethink your statement. You cannot get more motive energy than the energy put into the propeller.

> I can make a car use 50% less fuel an infinite amount of times

No, you can't. Conservation of energy applies.

P.S. I didn't "add" them, either. 90% x 115% => 103.5%

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Re:MT-Propeller 11 blade propeller delivers 15% increase in ... by moloch-hai on Friday January 06, 2023 @06:45PM (#34283038)
That is not how it works.

1-((1-0.9)x0.85) = 0.915, 91.5%. 15% better.

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Re:MT-Propeller 11 blade propeller delivers 15% increase in ... by davrosthedalek on Friday January 06, 2023 @08:12PM (#34283886)
(Your original point is not affected by this nitpicking, but:) A car, traveling any distance, between two points of constant height (in the gravity field), and neglecting work through friction (which is zero in the zero speed limit, albeit the movement is quite slow then, but a pumped out tunnel and mag lev gets you very close), requires no work, so no fuel. Technically.
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