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The angular velocity of a disc depends on the angle rotated theta as omega = theta² + 2*theta. Find the angular acceleration alpha at theta = 1 rad.

1. 8 rad/s²
2. 10 rad/s²
3. 12 rad/s²
4. None of these

Correct answer: 12 rad/s²

Solution

alpha = omega*d(omega)/d(theta) = (theta²+2theta)(2theta+2); at theta=1 this is (3)(4) = 12 rad/s².

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