How Do You Calculate Acceleration and Velocity in a Spinning Disk Problem?

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The discussion focuses on calculating acceleration and velocity in a spinning disk problem with a diameter of 0.1 m. To achieve an acceleration of 14 g's at the outer edge, the disk must rotate at 8.3 revolutions per second, equivalent to 498 RPM. The user initially struggled with calculating the speed of a point halfway between the axis and the edge, using the formula v = ωR. After conversion, the user arrived at an incorrect speed of 0.2075 m/s but later resolved the issue independently.

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Spinning Disk problem. Due tomorrow! Help please!

A disk with a diameter of 0.1 m is spinning about an axle perpendicular to the disk and running through its center.
a) How many revolutions per second would it have to rotate in order that the acceleration of the outer edge of the disk be 14 g's (i.e., 14 times the gravitational acceleration g)?

b) For the frequency determined in part (a), what is the speed of a point half way between the axis of rotation and the edge of the disk?

c) At this same frequency, what is the period of rotation of this "halfway point"?

d) How long does it take a point on the edge of the disk to travel 1 km?

I got questions a) which is 8.3 seconds.
I am stuck on b). I tried v=\omegaR. I also converted 8.3rev/s back to rpm which was 498rpm. So v=498rpm(.025m)=12.45meters/min. My answer needs to be in m/s so I divided by 60 and got .2075. It's not right. What am I doing wrong?
 
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Never mind I got it! :)
 

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