Imagine the ball on the left is given a nonzero initial speed in the horizontal direction, while the ball on the right continues to fall with zero initial velocity. What horizontal speed vx must the ball on the left start with so that it hits the ground at the same position as the ball on the right? Remember that the two balls are released, starting a horizontal distance of 3.0 m apart.
1 answer
The ball on the left must start with a horizontal speed of vx = 6.0 m/s. This is because the two balls will travel the same distance in the same amount of time, and the ball on the left must travel 3.0 m more than the ball on the right. Since the ball on the right has zero initial velocity, it will take 3.0 seconds for it to reach the ground. Therefore, the ball on the left must have an initial velocity of 6.0 m/s (3.0 m/s x 2 seconds) in order to reach the ground at the same time.