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Re: Why Moist Air Reduces Aerodynamic Lift (by James McGinn)

From Sylvia Else <sylvia@not.at.this.address>
Newsgroups sci.physics
Subject Re: Why Moist Air Reduces Aerodynamic Lift (by James McGinn)
Date 2016-01-17 23:50 +1100
Message-ID <dg1h08FlqaoU1@mid.individual.net> (permalink)
References <22c915a9-b027-430c-86ef-e94400ef80d5@googlegroups.com>

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On 16/01/2016 1:10 PM, James McGinn wrote:
>
> Before we can answer that question there are two other truths about
> aerodynamics that we need to clarify: 1) The energy that causes lift
> in an airplane doesn't come from the engine of the airplane. The
> energy that comes from the engine of the airplane is used to overcome
> drag. The energy that causes lift comes from air pressure--it comes
> from the atmosphere itself; And, 2) there is a finite amount of
> energy per volume of air. And, therefore, there is a finite amount of
> energy that can be efficiently extracted from a volume of air. This
> is why flying faster increases lift.  flying faster allows you to use
> more air and, thereby, extract more energy from it.  But flying
> faster doesn't increase the amount of energy per volume that an
> airplane gets out of the air.

If this nonsense were correct, one would expect lift to increase 
linearly with speed. But it doesn't. It increases with the square of the 
speed.

And it is nonsense. An aircraft does not extract energy from the air. 
The lift arises from the difference in pressure above and below the 
wing. The net result is an upwards (and slightly backwards) force on the 
aircraft, and a downwards force on the air (which accelerates downwards 
in response).

>
> The reason lift is reduced in in moist air is because liquid H2O has
> a very high heat capacity, which is just a fancy way of saying that
> it absorbs energy. Specifically, it is harder to extract the energy
> from air pressure because so much of it is soaked up by the liquid
> water that is in the air. So, stating that you know moist air is
> lighter because it reduces lift is scientifically invalid. It is an
> ignorance based assertion.

How much of your life are you spending constructing this gibberish?

Sylvia.

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Thread

Why Moist Air Reduces Aerodynamic Lift (by James McGinn) James McGinn <jimmcginn9@gmail.com> - 2016-01-15 18:10 -0800
  Re: Why Moist Air Reduces Aerodynamic Lift (by James McGinn) Helmut Wabnig <hwabnig@.- --- -.dotat> - 2016-01-16 09:59 +0100
    Re: Why Moist Air Reduces Aerodynamic Lift (by James McGinn) "Ross A. Finlayson" <ross.finlayson@gmail.com> - 2016-01-16 01:35 -0800
      Re: Why Moist Air Reduces Aerodynamic Lift (by James McGinn) James McGinn <jimmcginn9@gmail.com> - 2016-01-16 09:14 -0800
        Re: Why Moist Air Reduces Aerodynamic Lift (by James McGinn) Sergio <invalid@invalid.com> - 2016-01-16 19:17 -0600
        Re: Why Moist Air Reduces Aerodynamic Lift (by James McGinn) "Ross A. Finlayson" <ross.finlayson@gmail.com> - 2016-01-16 18:02 -0800
          Re: Why Moist Air Reduces Aerodynamic Lift (by James McGinn) James McGinn <jimmcginn9@gmail.com> - 2016-01-16 18:39 -0800
            Re: Why Moist Air Reduces Aerodynamic Lift (by James McGinn) Sergio <invalid@invalid.com> - 2016-01-16 23:26 -0600
          Re: Why Moist Air Reduces Aerodynamic Lift (by James McGinn) James McGinn <jimmcginn9@gmail.com> - 2016-01-16 18:41 -0800
            Re: Why Moist Air Reduces Aerodynamic Lift (by James McGinn) Sergio <invalid@invalid.com> - 2016-01-16 23:26 -0600
            Re: Why Moist Air Reduces Aerodynamic Lift (by James McGinn) "Ross A. Finlayson" <ross.finlayson@gmail.com> - 2016-01-16 22:41 -0800
              Re: Why Moist Air Reduces Aerodynamic Lift (by James McGinn) James McGinn <jimmcginn9@gmail.com> - 2016-01-16 22:52 -0800
                Re: Why Moist Air Reduces Aerodynamic Lift (by James McGinn) "Ross A. Finlayson" <ross.finlayson@gmail.com> - 2016-01-16 23:44 -0800
                Re: Why Moist Air Reduces Aerodynamic Lift (by James McGinn) James McGinn <jimmcginn9@gmail.com> - 2016-01-17 00:43 -0800
                Re: Why Moist Air Reduces Aerodynamic Lift (by James McGinn) Sergio <invalid@invalid.com> - 2016-01-17 10:16 -0600
    Re: Why Moist Air Reduces Aerodynamic Lift (by James McGinn) James McGinn <jimmcginn9@gmail.com> - 2016-01-16 08:54 -0800
      Re: Why Moist Air Reduces Aerodynamic Lift (by James McGinn) Sergio <invalid@invalid.com> - 2016-01-16 19:18 -0600
    Re: Why Moist Air Reduces Aerodynamic Lift (by James McGinn) James McGinn <jimmcginn9@gmail.com> - 2016-01-16 16:35 -0800
      Re: Why Moist Air Reduces Aerodynamic Lift (by James McGinn) Sergio <invalid@invalid.com> - 2016-01-16 19:18 -0600
  Re: Why Moist Air Reduces Aerodynamic Lift (by James McGinn) Sylvia Else <sylvia@not.at.this.address> - 2016-01-17 11:43 +1100
    Re: Why Moist Air Reduces Aerodynamic Lift (by James McGinn) Sergio <invalid@invalid.com> - 2016-01-16 19:19 -0600
    Re: Why Moist Air Reduces Aerodynamic Lift (by James McGinn) James McGinn <jimmcginn9@gmail.com> - 2016-01-16 17:46 -0800
      Re: Why Moist Air Reduces Aerodynamic Lift (by James McGinn) Sergio <invalid@invalid.com> - 2016-01-16 20:13 -0600
      Re: Why Moist Air Reduces Aerodynamic Lift (by James McGinn) Sylvia Else <sylvia@not.at.this.address> - 2016-01-17 15:47 +1100
        Re: Why Moist Air Reduces Aerodynamic Lift (by James McGinn) James McGinn <jimmcginn9@gmail.com> - 2016-01-16 21:04 -0800
          Re: Why Moist Air Reduces Aerodynamic Lift (by James McGinn) Sergio <invalid@invalid.com> - 2016-01-16 23:27 -0600
          Re: Why Moist Air Reduces Aerodynamic Lift (by James McGinn) Sylvia Else <sylvia@not.at.this.address> - 2016-01-17 16:57 +1100
            Re: Why Moist Air Reduces Aerodynamic Lift (by James McGinn) James McGinn <jimmcginn9@gmail.com> - 2016-01-16 22:21 -0800
              Re: Why Moist Air Reduces Aerodynamic Lift (by James McGinn) Sergio <invalid@invalid.com> - 2016-01-17 10:21 -0600
            Re: Why Moist Air Reduces Aerodynamic Lift (by James McGinn) R Kym Horsell <kym@kymhorsell.com> - 2016-01-17 06:32 +0000
              Re: Why Moist Air Reduces Aerodynamic Lift (by James McGinn) James McGinn <jimmcginn9@gmail.com> - 2016-01-16 22:43 -0800
                Re: Why Moist Air Reduces Aerodynamic Lift (by James McGinn) Sergio <invalid@invalid.com> - 2016-01-17 10:23 -0600
  Re: Why Moist Air Reduces Aerodynamic Lift (by James McGinn) Sylvia Else <sylvia@not.at.this.address> - 2016-01-17 23:50 +1100
    Re: Why Moist Air Reduces Aerodynamic Lift (by James McGinn) James McGinn <jimmcginn9@gmail.com> - 2016-01-17 11:05 -0800
      Re: Why Moist Air Reduces Aerodynamic Lift (by James McGinn) Sergio <invalid@invalid.com> - 2016-01-17 14:29 -0600
      Re: Why Moist Air Reduces Aerodynamic Lift (by James McGinn) Sylvia Else <sylvia@not.at.this.address> - 2016-01-18 11:52 +1100
        Re: Why Moist Air Reduces Aerodynamic Lift (by James McGinn) R Kym Horsell <kym@kymhorsell.com> - 2016-01-18 00:59 +0000
          Re: Why Moist Air Reduces Aerodynamic Lift (by James McGinn) Sylvia Else <sylvia@not.at.this.address> - 2016-01-18 13:18 +1100
            Re: Why Moist Air Reduces Aerodynamic Lift (by James McGinn) Solving Tornadoes <solvingtornadoes@gmail.com> - 2016-01-17 18:39 -0800
              Re: Why Moist Air Reduces Aerodynamic Lift (by James McGinn) Sergio <invalid@invalid.com> - 2016-01-18 00:32 -0600
              Re: Why Moist Air Reduces Aerodynamic Lift (by James McGinn) Odd Bodkin <bodkinodd@gmail.com> - 2016-01-18 13:17 -0600
                Re: Why Moist Air Reduces Aerodynamic Lift (by James McGinn) James McGinn <jimmcginn9@gmail.com> - 2016-01-20 10:02 -0800
                Re: Why Moist Air Reduces Aerodynamic Lift (by James McGinn) Sergio <invalid@invalid.com> - 2016-01-20 12:58 -0600
                Re: Why Moist Air Reduces Aerodynamic Lift (by James McGinn) Solving Tornadoes <solvingtornadoes@gmail.com> - 2016-01-22 16:38 -0800
                Re: Why Moist Air Reduces Aerodynamic Lift (by James McGinn) Sergio <invalid@invalid.com> - 2016-01-22 19:14 -0600
            Re: Why Moist Air Reduces Aerodynamic Lift (by James McGinn) R Kym Horsell <kym@kymhorsell.com> - 2016-01-18 13:44 +0000
        Re: Why Moist Air Reduces Aerodynamic Lift (by James McGinn) Solving Tornadoes <solvingtornadoes@gmail.com> - 2016-01-17 17:50 -0800
          Re: Why Moist Air Reduces Aerodynamic Lift (by James McGinn) Sergio <invalid@invalid.com> - 2016-01-18 00:34 -0600
  Re: Why Moist Air Reduces Aerodynamic Lift (by James McGinn) Sergio <invalid@invalid.com> - 2016-01-17 13:33 -0600
  Re: Why Moist Air Reduces Aerodynamic Lift (by James McGinn) Solving Tornadoes <solvingtornadoes@gmail.com> - 2016-01-25 10:14 -0800
  Re: Why Moist Air Reduces Aerodynamic Lift (by James McGinn) Solving Tornadoes <solvingtornadoes@gmail.com> - 2016-01-26 14:14 -0800
    Re: Why Moist Air Reduces Aerodynamic Lift (by James McGinn) James McGinn <jimmcginn9@gmail.com> - 2016-01-28 22:29 -0800
  Re: Why Moist Air Reduces Aerodynamic Lift (by James McGinn) James McGinn <jimmcginn9@gmail.com> - 2016-01-31 22:28 -0800

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