Final answer:
The force on a 0.25 kg baseball at half its maximum height is solely due to gravity and is calculated as 2.45 N downward, assuming no air resistance.
Step-by-step explanation:
The force on a 0.25 kg baseball thrown upward with an initial speed of 15 m/s when it reaches half its maximum height involves analyzing the forces in action. In this situation, only the force of gravity is acting on the ball when it reaches half its maximum height, assuming we are ignoring air resistance. The force due to gravity can be calculated using Newton's second law of motion, which states that the force is equal to the mass times the acceleration due to gravity (F = ma).
The mass of the baseball in question is 0.25 kg, and the acceleration due to gravity is approximately 9.8 m/s2 (assuming the location is on the Earth's surface). The force of gravity on the ball, therefore, is F = m * g = 0.25 kg * 9.8 m/s2 = 2.45 N directed downward. At half its maximum height, or indeed at any point in its trajectory (excluding air resistance), this is the only force acting on the baseball.