After hitting the wall, the ball rebounds at the original speed. The contact time between the ball and the wall is 0.2 seconds
The speed change is 2V and the time is t
So a = 2V / T
Substituting the data, we get a = 120
The speed change is 2V and the time is t
So a = 2V / T
Substituting the data, we get a = 120