The force of gravity causes all objects near the Earth's surface to fall with an acceleration of approximately 9.8 m/s². This value is often rounded to 10 m/s² for simplicity.

Here's why:

* Gravity: The Earth's gravitational pull is the force that attracts objects towards its center.

* Acceleration due to gravity (g): This is the rate at which an object's velocity changes due to the gravitational force. It is constant near the Earth's surface, regardless of the object's mass.

Important Note: Air resistance can affect the actual acceleration of falling objects, especially lighter objects.