When an object is in free fall, the only force acting on it is gravity. This force causes the object to accelerate downwards at a constant rate, regardless of its mass. In other words, all objects in free fall accelerate at the same rate. This is one of the fundamental principles of classical mechanics, known as the equivalence principle.
The acceleration due to gravity is caused by the gravitational field of the Earth, which is a region around the Earth in which the force of gravity is experienced. The strength of the gravitational field decreases as the distance from the center of the Earth increases, but for objects near the Earth's surface, the acceleration due to gravity is considered constant.
Therefore, during free fall, an object's velocity increases by an amount equal to g every second. This means that after one second of free fall, the object will have a velocity of g m/s, after two seconds it will have a velocity of 2g m/s, and so on. The acceleration is constant and continues until the object collides with another object or experiences a change in its motion.
