Here's why:
* Gravity: The primary force acting on a falling object is gravity. Gravity pulls the object towards the Earth's center, causing it to constantly accelerate.
* Vacuum: In a vacuum, there's no air resistance to oppose the force of gravity.
So, what actually happens is that the object continuously accelerates until it hits something.
However, in real-world scenarios, air resistance plays a significant role:
* Air Resistance: As an object falls through the air, it encounters resistance from the air molecules. This resistance acts in the opposite direction of the object's motion, slowing it down.
* Terminal Velocity: Eventually, the force of air resistance becomes equal to the force of gravity. At this point, the object stops accelerating and reaches a constant speed called terminal velocity.
Therefore, it's not a force that keeps a falling object from accelerating, but rather the balance between the force of gravity and air resistance that determines the object's acceleration.
