How come free fall which is accelerating is inertial motion?

Inertial motion is a motion with no acceleration.

In free fall the velocity of a body changes continuously.

Einstein deduced from the his equivalence principle that free fall is inertial but how?How come free fall which is accelerating is inertial motion?free fall is when the wind resistance is equal to the gravitational force pulling a body down. No acceleration anymore.How come free fall which is accelerating is inertial motion?I have not encountered the concept of inertial motion. Are you sure you have this right?How come free fall which is accelerating is inertial motion?I hope that this brief explanation helps you understand this:

It is such a common experience that thrown objects continue to move after they are released that we tend to forget that neither Newton nor Einstein were able to explain it. Why, for instance, is a batter able to strike a baseball and send it sailing out into center field. On close examination we discover that current physics simply does not account for this phenomenon in real terms. Modern physics looks upon the law of inertial motion as its basic and fundamental law. The principle is simple: a body left to itself remains at rest, or if it is put into motion it will continue to move in a straight line indefinitely unless interfered with in its movement. To us the concept is perfectly clear, plausible, and even self-evident. It seems obvious that this is the natural behavior of matter. But less than four hundred years ago to nearly everyone the idea seemed not only false, it seemed even absurd. The reason is that pure inertial motion does not occur in nature. It is utterly and absolutely impossible.



The concept of inertial motion dates from the seventeenth century. Until then it was believed that force was necessary for sustained motion. In his studies of trajectories and falling objects Galileo concluded that motion was a state like being at rest, and it was the change of motion that has to be accounted for. Newton then used inertial motion and gravity as a force of attraction to describe the orbital motions of the moon and planets. Einstein in his general theory dispensed with gravity as a force and curved space-time, but he kept Newton's inertial motion.



Newton's worldview consisted of a cosmic image and objects falling due to gravity. What Newton saw in the orchard, therefore, was an apple being pulled to the earth by the attraction of the greater mass. If, however, we think of the earth as a point mass, as Newton had to do for his calculations, the apple would have behaved quite differently.



When the apple dropped from the tree it would not have been stopped in its fall. It would have continued to fall at an ever increasing rate, zoomed past the earth-point at an enormous velocity, continued in its flight on the other side, decelerating as it goes, then stopping momentarily only to fall back again to complete an extremely elongated orbit and return to the tree with no net gain or loss in energy. What Newton saw was only a small slit of this much larger action. The reason the apple fell to the earth was simply because the earth bulged out and got in the way. When an object is thrown, therefore, it does not take on a continuous endless inertial motion. Any object released in space goes into an orbit, or what can be described as potentially an orbit. Any dropped object begins an orbit, and any motion added to it becomes a part of the orbit length. A thrown object adds the length of forced motion across its elongated elliptical fall and widens it on one end. To us it looks like a continuous motion that could go straight if thrown hard enough, but that is a misimpression. No more motion is created or continued than the forced displacement and the spontaneous motion of the fall.