A ball thrown straight upward takes 10 seconds for its up-and-down round trip. Because of air resistance, the time taken for the ball just to go up is

Question

Quizplus · Accepted Answer

The time taken for the ball to go up and come down is 10 seconds. Since the time taken for the ball to come down is equal to the time taken for it to go up, the time taken for the ball to just go up is half of the total time, which is 5 seconds. However, due to air resistance, the ball experiences a resistance force in the opposite direction of its motion, which slows it down. Therefore, the time taken for the ball to just go up is less than 5 s.

A Ball Thrown Straight Upward Takes 10 Seconds for Its