Angular acceleration - Please check if this is correct and

AI Thread Summary
The discussion revolves around calculating the angular acceleration of a car's tires as they decelerate from 90 km/h to 60 km/h over 85 revolutions. The user initially miscalculated the conversion from kilometers to meters, using 900 instead of the correct factor of 1000. After correcting this, they arrived at an angular acceleration of -1.605 rad/s², but another participant suggested a different value of -4.88 rad/s². Clarification on the conversion and calculations is sought to confirm the accuracy of these results. The thread highlights the importance of proper unit conversion in physics problems.
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Angular acceleration - Please check if this is correct and...

Homework Statement



Question:

Each of the tires of a car makes 85.0 revolutions as the car reduces its speed uniformly from 90.0 km/h to 60.0 km/m, The tires have a diamater of .900m.

Find initial and final angular Velocities

Find the angular acceleration of tires in rad/s^2

My answers: Please tell me if that's right, because I have NO idea if its correct.

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Homework Equations





The Attempt at a Solution

 
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If I am interpreting your work correctly, you are changing the km to m by multiplying by 900 instead of by 1000.

I think that the rest is OK.
 


Oops lol

Where wherever I have 900, change to 1000 correct? Just to be sure :)

Because when I change that, I get -1.60 is that correct for this question?

Because someone told me they got -4.88 ?
 
Last edited:


I got angular acc = -1.605rad/sec^2.
 
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