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Lift Against Gravity
Picture: Indoor Skydiving Bottrop - A vertical Windtunnel - What would happen if a parachute was activated
now? The abrupt realisation: swapping an inertial system has consequences
(see also "Flow and The Wind Tunnel")
Here we reduce the term gravity to the earth's gravity.
Counteracting gravity means applying an opposing force.
It does not matter whether the cause of gravity has already been determined.
As an ether theory, according to Einstein's ART, in quantum physics as a
graviton or otherwise. What can we observe and measure? Let's just look at
it from the point of view of the effect, classical mechanics. The acceleration
due to gravity is 9.8m/s². The gravitational constant can be ignored at the
heights at which we fly.
Example skydiver: In the first second 4.9m were covered, in the second second
already 19.6m and in the third second 44.1m (neglecting the air resistance).
This increase in speed (no uniform movement) would only continue in a vacuum,
but fortunately the air resistance increases so that the final speed is reached
after approx. 7 seconds. Obviously, the air resistance (acceleration of air
downwards by the falling jumper) generates a force which turns the acceleration
due to gravity (m/s²) for the jumper into a constant sinking speed (m/s) for
the jumper. Aircraft also have a vertical speed - not a vertical acceleration.
Also measured in m/s, although this is only 0 m/s in horizontal flight.
Lift is the counterforce to gravity. Vertically acceleration becomes vertically speed. Since flying
takes place in the air, an airplane can only act on the air to generate a
counterforce.
