The acceleration of gravity is the same for all objects, regardless of their mass or composition. This is a fundamental principle of physics known as the equivalence principle, which states that the gravitational force and inertial force are equivalent.

Here's why:

* Gravity acts on all mass equally. The force of gravity is directly proportional to the mass of the object. A heavier object will experience a greater gravitational force, but it also has more inertia (resistance to change in motion).

* Inertia resists acceleration. The larger the mass, the greater its inertia. This means it takes more force to accelerate a heavier object.

* The force and inertia balance out. The increased force of gravity on a heavier object is perfectly balanced by the increased inertia, resulting in the same acceleration for all objects.

Think of it like this:

Imagine dropping a feather and a bowling ball from the same height. You might think the bowling ball would hit the ground first because it's heavier, but in a vacuum (where air resistance is negligible), both objects would fall at the same rate and hit the ground simultaneously.

However, there are some nuances:

* Air resistance: In reality, objects experience air resistance, which affects their acceleration. This is why a feather falls more slowly than a bowling ball in air.

* Gravitational field strength: The acceleration due to gravity varies slightly depending on location and altitude. For example, the acceleration due to gravity is slightly higher at the poles than at the equator.

In summary: The acceleration of gravity is constant for all objects in a given gravitational field, regardless of their mass or composition. This is because the force of gravity and the object's inertia always balance out.