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Joined 2 years ago
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Cake day: July 1st, 2023

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  • Article is paywalled, so thanks for posting the actual study. This section seems in direct conflict with the article’s title:

    Given the … clear evidence that the epicenter of the SARS-CoV-2 pandemic was at one of only four markets in Wuhan that sold live wildlife from plausible intermediate host mammal species, either the closest-inferred ancestor or the direct ancestor of SARS-CoV-2 likely moved from an area in or around Yunnan province, to Hubei province, via the wild and farmed animal trade.

    In sum, the study doesn’t challenge that Covid-19 originated in Wuhan; but instead, explores the genetic backgrounds of the bats with the closest links to Covid-19.














  • From your source:

    {The upper flow is faster and from Bernoulli’s equation the pressure is lower. The difference in pressure across the airfoil produces the lift.} As we have seen in Experiment #1, this part of the theory is correct.

    Sure, it might be more complicated and there are other forces at play. Also, top and bottom air molecules may not reach the backside of an airfoil at the exact same time, but that doesn’t diminish the effects of this pressure differential on lifting force.


  • That lift explanation is innacurate/incomplete. While there may be some equal and opposite forces depending on the angle of attack, the primary reason for lift is due to Bernoulli’s Principle. Airfoils have a rounded upper surface with a longer path for air to take, relative to the underside. This requires air to move at a higher velocity over the top, and since A1 x V1 x P1 = A2 x V2 x P2, pressure over the airfoil decreases. It is this pressure differential that creates lift.

    In regards to aircraft, Newton’s third law of motion applies to thrust from a propeller or jet engine.