In free fall, the acceleration is due to gravity. This is often denoted as g, and its approximate value near the Earth's surface is 9.8 m/s². This means that every second, the speed of a freely falling object increases by 9.8 meters per second.

Here's a breakdown:

* Free Fall: This refers to the motion of an object solely under the influence of gravity. Air resistance is assumed to be negligible.

* Acceleration: This is the rate of change of velocity. In free fall, the velocity constantly increases as the object falls.

* Gravity: This is the force of attraction between any two objects with mass. The Earth's gravity pulls objects towards its center, causing them to accelerate downwards.

Important Points:

* The value of g (9.8 m/s²) is an approximation. The actual value can vary slightly depending on location and altitude.

* Free fall acceleration is constant, meaning the speed of the falling object increases at a steady rate.

* The direction of acceleration is always downwards, towards the Earth's center.

Example:

Imagine dropping a ball from a height. Initially, the ball is at rest (0 m/s). After 1 second, its velocity will be 9.8 m/s. After 2 seconds, its velocity will be 19.6 m/s, and so on. The ball continues to accelerate downwards at 9.8 m/s² throughout its fall.