Calculating Average Acceleration During Ball-Wall Collision

[krazykaci]

A tennis ball with a speed of 25.1 m/s is moving perpendicualr to a wall. After striking the wall, the ball rebounds in the opposite direction with a speed of 12.8 m/s. Take "twords the wall" to be a positive direction. If the ball is in contact with the wall for 0.0105 s, what is the average acceleration of the ball while it is in contact witht he wall? Answer in units of m/s2

where do i start here?

~KACI

 

[EP]

Look at your kinematic equations. Find one that you can solve for average acceleration. Isolate it and solve it.

 

[krazykaci]

so v.= 25.1 v=12.8 t= 0.0105 then I use v=v.+a(t) to solve?

 

[tony873004]

yes, but use algebra to re-write that formula so it reads:

a = something.

 

[Tomsk]

The ball changes direction, so you need to change the sign of one of the velocities.

 

[krazykaci]

thanks! =)