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Ch 09: Rotation of Rigid Bodies

Chapter 9, Problem 9

CALC A fan blade rotates with angular velocity given by ω_z(t) = g - bt^2, where g = 5.00 rad/s and b = 0.800 rad/s^3. (a) Calculate the angular acceleration as a function of time.

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Welcome back everybody. We are given the formula for angular velocity as a function of time for some rotating particle. And it is given as follows, C. Which is a constant equal to 4.2 -3. Another constant equal to 0.25 times our time squared. And we need to find the angular acceleration as a function of time. Well this is going to be just the derivative of our angular velocity with respect to time. So let's go ahead and take the derivative of this equation right here, term by term derivative of 4.2, it's a constant. So it's just gonna be zero minus. We have this term that too is gonna come down in front times 0.5 Times are T. Which gives us that our angular acceleration as a function of time equal to negative 0. radiance per second cubed times time corresponding to our answer choice of Thank you all so much for watching. Hope this video helped. We will see you all in the next one.
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Textbook Question
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Textbook Question
CALC A fan blade rotates with angular velocity given by ω_z(t) = g - bt^2, where g = 5.00 rad/s and b = 0.800 rad/s^3. (b) Calculate the instantaneous angular acceleration α_z at t = 3.00 s and the average angular acceleration α_av-z for the time interval t = 0 to t = 3.00 s. How do these two quantities compare? If they are different, why?
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Textbook Question
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