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Second PROOF for GRAVITY EQUATION

 

We know that for an object in space not to be affected by earth's gravity, it must be at an infinite distance, "ra", from earth's surface, "re". To fall to earth, this object must be pushed slightly. It will eventually strike the earth with an impact velocity, "ve", which can be found because we know its kinetic energy, "Ek", on impact, is equal to its original potential energy, "Ep". Average gravity during the fall is "gave". Gravity at earth's surface is "ge". Gravity at the infinitely remote point is "ga". "F" is force.

Ek = Ep
Ek = (1/2)mve2
Ep = Fra
F = ma or mgave

(1/2)mve2 = Fra

(1/2)mve2 = mgave ra

m divides out of the equation.

(1/2)ve2 = gavera

ve2 = 2gavera


From equation on page 8:

B = 1 / [(ra/re) + 1]

When ra is infinite, ra/re is so
great that "+1" is negligible, so

B = 1 / (ra / re) = re / ra


From equation on page 8:

gave = Bge + (1 - B)ga

At distance ra, ga is zero, so

gave = Bge = (re / ra)ge


From above:

ve2 = 2gavera

ve2 = 2(Bge)ra

ve2 = 2[(re / ra)ge]ra

ve2 = 2rege

ve = (2rege) 1/2


The energy needed for a rocket to escape from earth is the same as its kinetic energy from falling from an escape distance, so ve is its escape velocity.

Since the rocket must have fallen at the same rate as the nether surrounding it would have fallen, the velocity of the nether at the earth's surface would also be ve.
The equation ve = (2rege) 1/2 can be generalized as
v = (2rg) 1/2 or g = v 2 / 2r.


So the escape velocity for any celestial body at any point is the same as the instantaneous velocity of the nether moving past at that point.
 
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