If the ball is in contact with the player's head for 20 ms, what is the average acceleration of the ball? (Note that the force of gravity may be ignored during the brief collision time.)

To calculate the average acceleration of the ball, we need to know its change in velocity and the time interval during which this change occurs. In this case, we know that the ball is in contact with the player's head for a duration of 20 milliseconds (0.02 seconds). However, we are not given any information about the initial and final velocities of the ball.

To calculate the average acceleration in this situation, we can use the equation:

average acceleration = (final velocity - initial velocity) / time interval

Since we do not have the exact velocities, we cannot calculate the average acceleration precisely. However, we can make some assumptions for the sake of explaining the process.

Let's assume that the initial velocity is zero, which means the ball starts at rest. The final velocity would then be the velocity of the ball right after it leaves the player's head. Without any information about the ball's launch velocity or the collision characteristics, we cannot determine the final velocity precisely. However, for the purposes of explanation, let's assume that the ball leaves the player's head with a final velocity of 10 meters per second.

Plugging these values into the average acceleration equation, we get:

average acceleration = (10 m/s - 0 m/s) / 0.02 s

average acceleration = 500 m/s^2

Keep in mind that these values are purely hypothetical. Without additional information, we cannot provide an accurate calculation of the average acceleration in this specific scenario.