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It's easy to misunderstand explanations when they don't really explain anything. One explanation
that is especially confusing is the force of gravity. The problem is that gravity is an equation that describes how things move in relation to each other. It is not an explanation but an observation which is not the same thing at all. To mathematically describe something is not the same as understanding what it is.
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A very non-intuitive characteristic of gravity is that everything falls at exactly the same rate regardless of mass. Drop a BB and a canon-ball from the same height at the same time they will both hit the earth at the same time; weight is irrelevant. This is significant.
What is happening is that the force required to move some object dissipates until it reaches zero. At that instant the object has no weight. At this point,with the force completely spent, there is nothing left to keep it aloft. It isn't a force pulling the object toward earth bit rather the lack of any force holding it up.
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Since everything falls at the same rate (32fps2) regardless of weight, it becomes
obvious that it is the complete absence of force that's responsible for the illusion of a force of
gravity. The only force is that required to raise an object in the first place. The formula,
f=ma, doesn't really apply to raising an object since acceleration is immaterial. All we need to
know is how much effort is required to raise and object and how high it is raised. One the object
begins falling, the acceleration is always the same: 32fps2) A force of gravity is an unnecessary complication.
The same applies to notions of weight since all we really know is how much effort it takes to move something. Nothing has weight until we try to move it and the movement appears to be a force. Plain old inertia is all we really have to understand to account for all the attributes of a force of gravity.
Most of the time the force necessary to move an object from the surface of the earth will launch the object in a parabolic arc. The object ascends until the force that launched it dissipates to zero. At the apogee of this arc, for just an instant, the object is weightless. Just after that, the absence of any force holding the object up causes the object to mirror the force that sent it aloft in the first place.
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This is interesting because, regardless of the force launching an object, it falls at the same
rate. This must mean that only the minimum force required is preserved, any beyond that is lost at
the apogee of the arc the object follows. This means that neither the launching force nor the mass
of the object launched are relevant. The only measure left is 32fps2) that is all there is to know about gravity.
This invites the retort, "Jump off a building and see if you fall" which is evidence of the power
of a popular delusion. If you stand atop a high building, it's the building holding you up.
Whether you climbed the stairs or took elevator is immaterial so f=ma likewise has no relevance.
All that matters is that stepping off the building results in "force" of 32fps2) No matter how you got to the top of the building, regardless of any effort it took, you will return to earth at exactly the same rate.
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We could explain all this as states of energy: at the top of the building you have acquired
potential energy but this energy only exists when it's expended. Again this energy is fictitious
since regardless of what we may think it is, it is manifested in the same old rate of falling:
32fps2) The forces and energies believed to exist are just different instances of the same phenomenon.
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