Angular Acceleration Homework: 1014.65°, 17.97 rad/s

[dr2112]

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

 

[alphysicist]

Hi dr2112,

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:

$$\Delta\theta = \omega_0 t + \frac{1}{2}\alpha t^2$$

 

[dr2112]

Hi dr2112,



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

$$\Delta\theta = \omega_0 t + \frac{1}{2}\alpha t^2$$

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

 

[alphysicist]

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?