Compact disk angular acceleration

AI Thread Summary
A compact disc accelerates from rest to 5200 RPM over 620 radians, completing 99 revolutions during this time. To find angular acceleration, users can apply constant acceleration equations, substituting angular variables for linear ones. The initial and final angular velocities, along with the angular displacement, are key to solving for angular acceleration. Once angular acceleration is determined, the time to reach the final speed can also be calculated. Understanding these concepts is essential for solving the problem effectively.
jkhays
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Homework Statement



A compact disc speeds from rest to 5200 rpms in 620 rad. Diameter is 5.0cm
-how many revolutions did it make in this time
-what is the angular acceleration in rad/s^2
-how long does ti take to reach this speed

Homework Equations


The Attempt at a Solution


i was able to find the first part by
620(180/π) = 35523 dividing that by 360 and getting 99 revolutions

for the last 2, i am completely lost to where i even begin solving them.thank you..
 
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welcome to pf!

hi jkhays! welcome to pf! :smile:

you can use the usual constant acceleration equations, with angular acceleration velocity and displacement instead of ordinary (linear) acceleration velocity and displacement :wink:
 
You know ω initial and ω final, and Δθ. You can solve for angular acceleration using one of the kinematics equations for constant acceleration. Once you have alpha you can solve for t.
 

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