Final answer:
Air resistance on a baseball increases as the square of its velocity, and as it falls from a height, such as from a balloon, this resistance will increase until it reaches terminal velocity. The work done by air resistance is negative, taking away kinetic energy from the baseball and is calculable using the work-energy principle.
Step-by-step explanation:
The air resistance acting on the baseball varies with the velocity of the baseball in a complex way. Generally, air resistance, also known as drag, increases with the square of the velocity for objects moving at high speeds in air. This means that as the baseball speeds up while falling, the amount of air resistance it experiences also increases. However, once the baseball reaches a certain speed, known as the terminal velocity, the air resistance force balances out the gravitational force, and the baseball falls at a constant velocity.
Considering the work done by air resistance, we must remember that work is the product of force and the distance over which that force acts. If the force of air resistance is acting against the motion of the baseball, this will cause a negative work, taking away kinetic energy from the baseball and slowing it down.
For example, in a similar scenario where a baseball is hit at home plate and lands in the bleachers, if the initial and final speeds are known, along with the distance travelled, one could calculate the work done by air resistance using the work-energy principle. This principle states that the work done by all forces acting on an object is equal to the change in kinetic energy of that object.