Acceleration Vectors: Calculating Average Acceleration in a Direction Change

[GodOfYou]

Homework Statement

A Soccer player is running down the field with a ball at a speed of 4.0 m/s. He cuts to the right at an angle of 30.0^o to his original direction to receive a pass. If it takes him 3.0s to change is direction, what is his average acceleration during the turn?

Homework Equations

a = v / t

a²+b²=c²

Sin, Cos, Tan ex. Cos 45^o = delta d1 / delta d2

The Attempt at a Solution

I have drawn the triangle In attachment.
The dotted lines are me making the triangle.

Then I broke the top triangle into a right angle triangle (in second attachment)

and now I am stuck.. I have never worked with angles in this type of problem and I need help.

Thanks,
Jason

 

[ƒ(x)]

Break both his old and new velocity into components.

 

[GodOfYou]

so when he turns to the right he will still be moving at 4.0 m/s?

 

[Redbelly98]

Yes, it looks like we are supposed to assume the speed is still 4.0 m/s after the turn.