Figuring out angular velocity from θ = 2.0 + 4.0t^2 + 2.0t^3

AI Thread Summary
To find the angular velocity from the equation θ = 2.0 + 4.0t² + 2.0t³, differentiate θ with respect to time t, yielding w = dθ/dt = 8.0t + 6.0t². At t = 0, the angular position is 2.0 radians and the angular velocity is 0 rad/s. At t = 4.0 s, the angular velocity can be calculated as w = 8.0(4) + 6.0(4)², resulting in 128 rad/s. The angular acceleration can be determined by differentiating the angular velocity, and it is not constant due to the presence of the t² term in the angular velocity equation. Understanding these calculations is essential for solving the problem accurately.
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Homework Statement



The angular position of a point on a rotating wheel is given by θ = 2.0 + 4.0t2 + 2.0t3, where θ is in radians and t is in seconds. At t = 0, what are (a) the point's angular position and (b) its angular velocity? (c) What is its angular velocity at t = 4.0 s? (d) Calculate its angular acceleration at t = 2.0 s. (e) Is its angular acceleration constant?

Homework Equations



w = dθ/dt I am stuck on figuring out how to angular velolcity is:

(8.0rad/s^2)t + (6.0rad/s^3)t^2

as my professor put it, its buggin me how i can't put two and two together.

The Attempt at a Solution

 
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Stonem42 said:
w = dθ/dt I am stuck on figuring out how to angular velolcity is:

I'm stuck on what you're stuck on. What?
 
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