Spinning the wheels: intro to angular momentum

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To determine the angular momentum L of an object with rotational inertia I that starts from rest and rotates with a constant angular acceleration alpha, the angular velocity omega can be found using the equation omega = alpha * t. The relationship for angular momentum is L = I * omega, which leads to L = I * (alpha * t). The discussion also draws parallels to linear motion, suggesting that similar principles apply when calculating speed from acceleration and time. Understanding these concepts is crucial for solving problems related to angular momentum effectively.
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An object has rotational inertia I. The object, initially at rest, begins to rotate with a constant angular acceleration of magnitude alpha. What is the magnitude of the angular momentum L of the object after time t?
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So I know that I have to find angular velocity and use the equation
L=angular momentum= I(omega) ... so how do i find this omega in terms of alpha and t??

I know that torque = r*F and L = r*momentum ... and F=m(alpha)(r) ? ..
 
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If it were a linear velocity problem, could you find the speed given acceleration and time? Use similar thinking.
 
ah that's too easy .. thanks lots:)
 

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