Final answer:
The air resistance acting on the 6.5-cm-diameter ball at its terminal speed of 25 m/s can be calculated using the formula: Force of air resistance = (0.5) x (density of air) x (velocity of ball)^2 x (cross-sectional area of ball). The cross-sectional area of the ball can be calculated using the formula for the area of a circle. Once you have the density of air, you can substitute the values and calculate the air resistance force.
Step-by-step explanation:
The air resistance acting on the 6.5-cm-diameter ball when it reaches its terminal speed of 25 m/s can be calculated using the equation:
Force of air resistance = (0.5) × (density of air) × (velocity of ball)^2 × (cross-sectional area of ball)
Given that the diameter of the ball is 6.5 cm, the radius will be 3.25 cm or 0.0325 m. Therefore, the cross-sectional area of the ball can be calculated as:
Cross-sectional area of ball = π × (radius of ball)^2
Substituting the values into the equation, we get:
Force of air resistance = (0.5) × (density of air) × (25 m/s)^2 × (π × (0.0325 m)^2)
Once you have the density of air, you can calculate the air resistance force.