The pull of gravity does not change the length of an object. However, it can cause an object to deform, which can make it appear longer or shorter. For example, if you hang a weight from a spring, the spring will stretch and become longer. This is because the weight is pulling the spring down, which causes the coils of the spring to move apart.

However, the actual length of the spring has not changed. The atoms that make up the spring are still the same distance apart, they are just arranged in a different way. If you remove the weight, the spring will return to its original length.

So, while the pull of gravity can cause an object to deform, it does not actually change the length of the object.