Final answer:
The initial velocities of the tennis ball in the x- and y-direction are 28.0 m/s and 0 m/s, respectively. The ball's acceleration is 0 m/s² in the x-direction and 9.81 m/s² downward in the y-direction.
Step-by-step explanation:
The question is about projectile motion and the calculations involved in finding various components of a tennis ball's movement after being struck.
First, we need to determine the initial velocity of the ball in the x- and y-direction. Given that no forces act on the ball in the horizontal direction after it leaves the racket, the initial velocity in the x-direction is equal to the velocity with which it moves horizontally, which is 28.0 m/s.
Since gravity is the only force acting on the ball in the y-direction, the initial vertical velocity component is 0 m/s (assuming it was hit horizontally).
As for the acceleration, in the x-direction, there is no acceleration because no external forces are acting on the ball horizontally once it leaves the racket, meaning the acceleration in the x-direction is 0 m/s2. In the y-direction, the acceleration is due to gravity, which is approximately 9.81 m/s2 downward.