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Cake day: July 1st, 2023

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  • 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.



  • I always prefer to sit unless I’m in a huge hurry. It’s called a restroom for a reason. I’m going to take a break, browse Lemmy or something, and otherwise “rest”. I’ll return to work when I’m ready.

    What really pisses me off is when I hear someone enter another stall to take a standing piss. They rarely put the seat up and always get pee all over everything. If you’re going to stand, use a urinal. There’s nothing more pathetic than being afraid to whip your dick out beside your fellow man, and instead, choose to piss on the place where others want to take a sit.















  • There is no perfect vacuum, even in deep space. In the space of our Solar System, there is on average 5 atoms in every cubic centimeter. In interstellar space, there is on average 1 atom every cubic centimeter. In intergalactic space, there is on average 1 atom every 100 cubic centimeters. It’s a gradient, but much like the perfectly straight lines and flat planes in the original question, perfect vacuum is a theoretical construct that is impossible to achieve in our reality.