Why Are Parts B-D of My Torque Calculations Incorrect?

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The discussion centers on the incorrect torque calculations in parts B-D of a homework problem. The user derived torque from angular momentum but is confused about the sign convention for clockwise rotation. It is clarified that since clockwise is considered negative, the user should reverse the signs in their final answers. The correct answers are indicated in the green portions of their work. Understanding the sign convention is crucial for accurate torque calculations.
VitaX
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Homework Statement



vhqd91.jpg


Homework Equations



Torque is equal to the derivative of angular momentum with respect to time

The Attempt at a Solution



I took the derivative of each function given in parts a - d and plugged in the value for t to get my answer for the torque. I don't quite understand why parts b - d are wrong. Since it says clockwise do I reverse my signs in my final answer? The green portions represent correct answers.
 
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Hi VitaX! :smile:
VitaX said:
… Since it says clockwise do I reverse my signs in my final answer?

clockwise is negative, so yes, you do reverse the sign (from the start) :wink:
 

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