Motion — Describe

How does a falling object's motion change with and without air resistance, and what is terminal velocity?

Without air resistance, a falling object accelerates uniformly at the acceleration of free fall, g, since its weight is the only force acting. With air or liquid resistance, the object initially accelerates, but as its speed increases the resistive force increases too; when the resistive force becomes equal to the weight, the resultant force is zero and the object falls at a constant maximum speed called the terminal velocity.