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Old 10-20-2020, 12:12 AM   #66 (permalink)
Vman455
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Quote:
Originally Posted by Hersbird View Post
We dont really know how gravity works. Often the more we know about something will show the less we really know about something.
Yes, we do know how it works: gravity acts as an inverse-square, conservative vector field proportional to the mass of two objects. What we don't know is why it exists, but that doesn't hinder our understanding of its functioning, which we have figured out over hundreds of years of observation and mathematical reasoning well enough to launch objects to other planets with incredible accuracy.

Aerodynamics is a more nascent field than gravitational physics, and there's a lot left to figure out. Many formulae in textbooks are explicitly identified as empirical. For example,

cD = cD0 + k(cL^2)

It isn't an exact formula; the constant k has to be measured experimentally for any given car. But there seems to exist some relationship between lift and drag given generally by the formula, derived from the observation that most cars achieve their lowest drag when lift is zero or close to zero.

At the same time, that's what appeals to me--we haven't figured it all out yet. There are phenomena which remain to be discovered.
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