Finall Answer:
The baseball thrown upward at an initial speed of 14.9 m/s experiences a vertical motion under gravity's influence at an acceleration of 9.80 m/s².
Step-by-step explanation:
When the baseball is thrown upward, its initial velocity is 14.9 m/s. Due to gravity acting on it, the ball's vertical motion slows down until it reaches its maximum height, where its velocity becomes zero before starting to fall back down. The acceleration due to gravity, 9.80 m/s², causes the ball's velocity to decrease by 9.80 m/s every second until it reaches its peak and starts descending.
This consistent acceleration value acts to decrease the ball's upward speed until it momentarily stops before changing direction and accelerating downward due to gravity's pull. Eventually, the ball returns to its starting point after completing its trajectory upward and downward.