Angular Acceleration Homework: 1014.65°, 17.97 rad/s

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The discussion revolves around a physics homework problem involving a wheel rotating with constant angular acceleration. The calculations show that the wheel rotates an angle of 1014.65 degrees between t=0 and t=3.67 seconds, and its angular speed at 4.1 seconds is 17.97 rad/s. Some participants question the correctness of the initial calculations, specifically regarding the need to square the time variable in the angular displacement formula. There is also confusion about tangential and total acceleration values, suggesting a possible mix-up with a different problem. The conversation highlights the importance of correctly applying formulas in angular motion problems.
dr2112
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Homework Statement


wheel rotates w constant acceleration 3.65rad/s2
angular speed is 3.00 rad/s at t=0
a)what angle does wheel rotate between t=0 and t=3.67s?
b)what is angular speed of wheel at 4.1s?


Homework Equations


wt+1/2alphat
(3.00rad/s)(3.67t)+1/2(3.65rad/s2)(3.67)2=17.70rad
17.70rad*360degrees/628rad=1014.65degrees

w=w0+alpha t
3.00rad/s+3.65rad/s2(4.1s)=17.97rad/s

The Attempt at a Solution


a=1014.65 degrees
b=17.97rad/s

 
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Hi dr2112,

dr2112 said:

Homework Statement


wheel rotates w constant acceleration 3.65rad/s2
angular speed is 3.00 rad/s at t=0
a)what angle does wheel rotate between t=0 and t=3.67s?
b)what is angular speed of wheel at 4.1s?


Homework Equations


wt+1/2alphat
(3.00rad/s)(3.67t)+1/2(3.65rad/s2)(3.67)2=17.70rad

I don't believe this is correct. The final t needs to be squared:

<br /> \Delta\theta = \omega_0 t + \frac{1}{2}\alpha t^2<br />
 
alphysicist said:
Hi dr2112,



I don't believe this is correct. The final t needs to be squared:

<br /> \Delta\theta = \omega_0 t + \frac{1}{2}\alpha t^2<br />

Ok how is 1.60 m/s^2 for tangential and 8.61 m/s^2 for total acceleration?
 
dr2112 said:
Ok how is 1.60 m/s^2 for tangential and 8.61 m/s^2 for total acceleration?

Is this for a different problem, or is there more to the problem in your first post?
 
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