Final answer:
Balls reduce speed as they ascend higher due to the force of gravity and air resistance. Gravity pulls objects towards the Earth, and has to be overcome by the force that initially threw the ball upwards. In addition, as a ball moves through the air, the air resistance it experiences can also slow its speed.
Step-by-step explanation:
The reason why balls reduce speed when they ascend higher is due to the force of gravity and air resistance. As a ball ascends higher, it is expanding energy against the force of gravity. This energy expenditure will slow down the ball's upward speed over time, until it eventually stops ascending and starts descending.
Gravity is a constant force that pulls objects towards the Earth's center. When a ball is thrown upwards, it fights against this force, causing it to lose speed as it ascends. The upward force exerted to throw the ball gradually depletes, and the gravity eventually pulls it back to Earth.
Air resistance is another factor to consider. When a ball moves through the air, it experiences a force - air resistance - opposing its motion. As the ball's speed increases, the force of air resistance also increases, causing the ball's speed to decrease.
If the ball is thrown at an angle, the travel distance can also be affected. The path of the thrown ball becomes an arc in such cases, with the ball slowing down as it reaches the peak and picks up speed as it descends due to gravity.
Learn more about Gravity and air resistance