Not calc based tangential and angular acceleration

AI Thread Summary
The discussion focuses on calculating the magnitude of angular acceleration for a disk rotating with constant angular acceleration. The initial angular speed is given as 2π rad/s, and after rotating through 10π rad, the final angular speed is 7π rad/s. Participants suggest using kinematic equations that relate angular velocity, angular acceleration, and angular displacement, rather than the basic definitions involving time. There is a recommendation to learn and memorize the equations of motion for translational motion as a foundational step. The conversation emphasizes the need for clarity in applying the correct equations to solve the problem effectively.
darlagatsch
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Homework Statement


a disk rotates with constant angular accel. the initial angular speed of the disc is 2pie rad/s. After the disk rotates through 10pie rad, the ang speed is 7pie rad/s.

Homework Equations


a. what is the mag of the angular accel?


The Attempt at a Solution


alpha=delta omega/delta time
omega=delta theta/delta time
etiher or both?
 
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darlagatsch said:

Homework Statement


a disk rotates with constant angular accel. the initial angular speed of the disc is 2pie rad/s. After the disk rotates through 10pie rad, the ang speed is 7pie rad/s.

Homework Equations


a. what is the mag of the angular accel?


The Attempt at a Solution


alpha=delta omega/delta time
omega=delta theta/delta time
etiher or both?
the first one has 2 unknowns and the second one is wrong...why not try one of the other kinematic equations for constant angular acceleration...the one that relates omega with alpha and theta?
 
i have no idea! HELLLP
 
darlagatsch said:
i have no idea! HELLLP
Well you seem to have known somehow that alpha=delta omega/delta time, how did you know that? You can find the equations on the link below, 4th slide:

http://www.colorado.edu/physics/phys2010/phys2010_fa11/LectureNotes/phys2010_fa11_lecture28.pdf

You should first learn, understand, and memorize the motion equations for translational motion.
 
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