Angular Velocity and Tangential Acceleration Explanation

AI Thread Summary
The discussion revolves around two questions regarding angular velocity and tangential acceleration of a rotating disk. For the first question, the user believes that the angular velocity of point Q, which is farther from the center, is the same as point P's, indicating a misunderstanding of angular velocity principles. In the second question, the user asserts that the tangential acceleration of a point on the rim is zero due to the disk rotating at a constant rate. However, the community emphasizes the need to show work for accurate assistance, highlighting the importance of demonstrating understanding in physics discussions. Overall, the thread seeks clarification on fundamental concepts of angular motion.
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angular velocity help!

Hi, I need help with the following 2 questions. My answers have *********
next to them. Any help is appreciated. Thank you.



1. A disk is rotating at a constant rate about a vertical axis through its center. Point Q is twice as far from the center of the disk as point P is. The angular velocity of Q at a given time is
Choices:
a) twice as big as P's
b) the same as P's *******************
c) half as big as P's
d) none of the above

i believe it's the same as P's, since and poing on radius r, has the same velocity on any point on the radius line.

2. When a disk rotates counterclockwise at a constant rate about a vertical axis through its center, the tangential acceleration of a point on the rim is
Choices:
a) positive.
b) zero. *******************
c) negative.
d) impossible to determine without more information.

i believe it's zero, since it's rotating at a constant rate, which means the acceleration is zero.

Any help is appreciated. Thank you.
 
Last edited:
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According to the PF Global Guidelines (to which you agreed), you have to show your work before you can receive help.
 
work is show to my answers.
 
anyone?
 
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