Why Is the Angular Velocity of a Clockwise-Spinning CD in the -y Direction?

AI Thread Summary
The discussion centers on determining the direction of angular velocity for a clockwise-spinning CD. The key point is that the answer is given as the -y direction, which some participants find confusing. Using the right-hand rule, the thumb points in the negative y-direction when considering the vertical y-axis as the axis of rotation. This interpretation aligns with the two-dimensional perspective of the problem. Understanding the application of the right-hand rule in this context clarifies why the angular velocity is considered to be in the -y direction.
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Homework Statement


A CD player spins a disc in a clockwise direction when looking at the player from the top. What is the direction of the angular velocity.


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The Attempt at a Solution


OK, the key for this practice exam says the answer is in the -y direction. I used the right hand rule to see that the direction is negative, but I thought it would be in the -z direction. Can someone explain why it is -y?
 
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I believe they have made the answer this way as you are only using two dimensions. If you take the vertical y-axis as the axle for the rotation, your right thumb will be pointing in the negative y-direction when you use the right hand rule.
 
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