I'm lost on this angular acceleration problem

AI Thread Summary
To find the angular speed of the car's wheels, the tangential speed of 26.94 m/s can be used directly. The diameter of the wheels is 76 cm, giving a radius of 0.38 m. The relationship between tangential speed and angular velocity is essential for the calculation. Using the tangential speed allows for the determination of the angular frequency of the wheel. This method effectively solves the problem of angular acceleration.
falcon0311
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Okay, so there's a car traveling 97km/h (26.94 m/s). It's wheels have a diameter of 76cm (0.76 m), so the radius of the wheels are 0.38 m. I'm supposed to find the angular speed of the wheels about the axle.

Can I say the speed of a tangent from the wheels is 26.94 m/s and use that to find the angular velocity?
 
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Originally posted by falcon0311

Can I say the speed of a tangent from the wheels is 26.94 m/s and use that to find the angular velocity?

Yes, that's exactly what you should do. 26.94 m/s is the velocity of a point on the outer rim of the wheel, so you can use that to calculate the angular frequency of the wheel.
 
http://physics.about.com/cs/rotationalmotion/a/010703.htm
 
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Thanks a bunch Chen!
 
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