Need Help with an Average Acceleration Problem

AI Thread Summary
The discussion revolves around calculating the average acceleration of a car making a turn while maintaining a constant speed of 14 m/s. The car turns onto a southwest street over 5.2 seconds, prompting a need to analyze the change in velocity due to the change in direction. Participants emphasize the importance of recognizing that while speed remains constant, the direction change affects velocity, necessitating a vector analysis. A hint is provided to calculate the components of the velocity before and after the turn to determine the change in velocity. The overall focus is on applying the definition of average acceleration in vector form to solve the problem.
xedothecat
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A car traveling with a constant speed of 14 m/s due west comes to an intersection where it makes a turn onto a southwest (45 degree) street. The car takes 5.2 seconds to complete the turn and the speed of the car does not change during this time. Find the average acceleration of the car. Report your answer in component form. Positive x points east and positive y points north.
 
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xedothecat said:
A car traveling with a constant speed of 14 m/s due west comes to an intersection where it makes a turn onto a southwest (45 degree) street. The car takes 5.2 seconds to complete the turn and the speed of the car does not change during this time. Find the average acceleration of the car. Report your answer in component form. Positive x points east and positive y points north.
Hello xedothecat. Welcome to PF !

According to the rules here at Physics Forums, you must show some effort before we can help you.

What have you tried?

Where are you stuck?

Since you're new here, I'll give a hint: Use the definition of average acceleration.
 
I drew a picture with the angle theta at 135 degrees. I tried to calculate the displacement vector's magnitude but I don't know the length of the other sides of the triangle I drew. I know that if the velocity is constant at 14 m/s and the turn takes 5.2 seconds, the total distance traveled is 72.8 meters and I know average acceleration is change in velocity over change in time. The change in time is 5.2 seconds and I don't know what the change in velocity is because if the velocity is constant, I don't get what I'm supposed to be calculating.
 
Velocity is a vector. The car changed direction, so the velocity changed, even though the SPEED remained constant. Write down the components of the velocity before and after the turn. This gives you the change in velocity.
 
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