Studying for a level 1 physics test. Help with circular problem?

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To solve the problem of a stationary wheel with a given torque, first calculate the moment of inertia (I) using the formula I = 1/2mr^2. Next, apply the relationship between torque, moment of inertia, and angular acceleration to determine the angular acceleration. Since the torque is constant, the angular velocity will increase linearly over time. After 15 seconds, calculate the angular velocity and convert it to frequency using the relation that angular velocity equals 2π times the frequency. The discussion concludes with gratitude for the assistance provided.
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A stationary wheel ?(solid cylinder) of radius .3m and mass of 1.75 kg has a 12 Nm torque applied to it. Determine the frequency of the wheel after 15 seconds.


I = 1/2mr^2

Am I supposed to find "I" first? What is the best way to go about this problem?
 
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Yes, find I, the moment of inertia of the cylinder. Then use the relation between torque, moment of inertia, and angular acceleration to get the angular acceleration. The angular velocity increases linearly with time under the effect of the constant torque. Find the value of the angular velocity 15 seconds after start. The angular velocity is 2pi times the frequency.

ehild
 
Thank you so much! I will let you know if I have anymore questions later on.
 

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