Since all the sub-atomic particles of a body that interact with gravity have the same mass or are bound together by nuclear forces they will all accelerate at the same rate.
It does not make any difference whether the body has billions of
these particles or trillions of particles, gravity exerts its force
equally on each individual particle. The number of particles determines the amount of the body's (inertial) mass and therefore its gravitational attraction power(GP).
A small body has fewer sub-atomic particles then a large body so it will not have as much total attractive force as the larger body and therefore not be able to create as much acceleration on the large body while the large body will be able to cause the small body to accelerate faster. For example - The earth's gravitational force (its G power) is much greater then the moon's G power so it will cause the moon to accelerate faster toward the earth then the moon can cause the earth to accelerate toward the moon BUT their combined acceleration toward each other will be the same as a 1000 lb. body (or any other body) accelerating toward each other.
While the body falls at the normal rate of 32.2'/second/second toward the earth, the earth accelerates toward the body at an infinitesimally small rate that would be hard to measure but their combined acceleration would be the same as the earth/moon combined rate.
Two bodies of equal mass would not fall toward each other because they would each have the same inertial requirement. Therefore the gravitational power of the body would be equal to the IR of the other body. Their IR (inertial requirement) and GP (gravitational power) would be equal and therefore cancel the other's acceleration.
Gravity by itself can never create the effect of weight. It always requires another force (Secondary force) acting on the body to create the effect of weight. The earth's suface exerts just enough force to STOP the gravitational acceleration of a body and then PREVENT any further gravitational acceleration this is manifested as the body's weight.
Since gravity is exerting its force on each sub-atomic particle of a body simultaneously in unison and since they all have the same mass there are no stresses acting on the body. They will all accelerate at the same rate. This is what fooled Einstein into thinking that there was no force acting on the falling person - but he was wrong.
Newton explained bodies fall at the same rate of acceleration because Gravity and Inertia are
exactly proportional. Einstein said they are equivalent.
The truth is - Inertia simply requires a force be exerted on a body for it to
accelerate and gravity is one of the "primary forces" that can fulfill this requirement.
Inertia and Gravity are not equivalent but they do work together. Inertia requires a certain amount of force for
a certain body to accelerate at a certain rate. Gravity is one of the primary forces that can do this.
Only the four primary forces are energy forces - they must be exerted
first for a body to accelerate - all other forces (SECONDARY FORCES)
can only alter the original primary forces in some manner.
Does a heavy object exert more downward force then a light object?
YES it exerts more TOTAL downward force BUT gravity does not exert
its force on the object as a whole, it exerts its force on each
individual sub-atomic particle that makes up the object simultaneously.
Gravity interacts with each individual sub-atomic particle simultaneously.
The SECONDARY FORCES cannot do this, they exert their force in succession, one body pushes against the next body which pushes against the next etc. etc.. A molecule pushes against the next molecule, an atom pushes against the next atom (even though, at this level they may not actually touching each other). This action causes the effect of weight to be created.
Donald Louis Hamilton - author of The MIND of Mankind; Human Imagination, the source of Mankind's tremendous power!
Ref. Book - "Mind of Mankind" published 1996, Chapt 18. "Weight, Its Relation to Inertia and Gravity"
For more see: Weight