A tennis ball with a speed of 6.0 m/s is thrown perpendicularly at a wall. After striking the wall, the ball rebounds in the opposite direction with a speed of 4.0 m/s. If the ball is in contact with the wall for 0.012 s, what is the average acceleration of the ball while it is in contact with the wall? Take the initial direction of motion to be the positive direction. (Indicate the direction of the acceleration by the sign of your answer.)

Initial velocity is given, final velocity is given, and the time is given. Using these, rearrange

v=u+at to solve for a.

The ball is slower after the bounce, so what sign will the acceleration be?

To find the average acceleration of the ball while it is in contact with the wall, we can use the equation for average acceleration:

average acceleration = change in velocity / time

First, let's determine the change in velocity. The initial velocity of the ball is +6.0 m/s, and after rebounding, the velocity becomes -4.0 m/s. Since the direction of motion is considered positive, we can represent the initial velocity as +6.0 m/s and the final velocity as -4.0 m/s.

Change in velocity = final velocity - initial velocity
Change in velocity = -4.0 m/s - (+6.0 m/s)
Change in velocity = -4.0 m/s - 6.0 m/s
Change in velocity = -10.0 m/s

Next, we need to determine the time the ball is in contact with the wall, which is given as 0.012 s.

Now, we can substitute the values into the formula:

average acceleration = change in velocity / time
average acceleration = -10.0 m/s / 0.012 s

Calculating this:

average acceleration = -833.33 m/s²

Therefore, the average acceleration of the ball while it is in contact with the wall is -833.33 m/s². The negative sign indicates that the acceleration is in the opposite direction of the initial motion.

To find the average acceleration of the ball while it is in contact with the wall, we need to use the formula for average acceleration:

average acceleration = (change in velocity) / (time taken)

In this case, the change in velocity is the final velocity minus the initial velocity.

The initial velocity of the ball is +6.0 m/s (positive because it is thrown perpendicularly at the wall).

The final velocity of the ball is -4.0 m/s (negative because it rebounds in the opposite direction).

The time taken is given as 0.012 s.

Let's plug in the values into the formula:

average acceleration = (-4.0 m/s - 6.0 m/s) / 0.012 s

= (-10.0 m/s) / 0.012 s

= -833.3 m/s^2

Since the initial direction of motion is taken as the positive direction, the negative sign of the average acceleration indicates that the ball experienced deceleration (acceleration in the opposite direction to its initial motion) while in contact with the wall.