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Rotational kinetic energy of a wheel

  • Thread starter richyr33
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  • #1
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Homework Statement



I have a wheel with a diameter of 1.4m and the radius of gyration is 0.42m. The wheel has a mass of 13kg. Calculate maximum rotational kinetic energy.

Homework Equations





The Attempt at a Solution



From this all i can do is calculate the moment of inertia which is the mass (x) radius of gyration squared which gives me 2.29kg/m squared.
As far as i am aware i need the angular velocity to calculate the kinetic energy but i have no velocity figures. Any help is much appreciated
 

Answers and Replies

  • #2
Doc Al
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As far as i am aware i need the angular velocity to calculate the kinetic energy but i have no velocity figures.
Without more information, there's not much you can do. Did you present the full problem exactly as given, word for word?
 
  • #3
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You have to know how many turns it took so you can use: [tex]\frac{1}{2}J_{\Delta}\omega^{2}=M_{\Delta}*\Delta\theta[/tex] to calculate the maximal angular speed.

Then you can just plug it in and find your answer .

Ps: JΔ of a wheel : [tex]J_{\Delta}=M*R^{2}[/tex]
 
  • #4
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yes that is all the information that is in the question. I have previously calculated a maximum linear velocity which i now assume is what i have to use to answer the question even though it makes no reference to it. Many thanks for your replies.
 
  • #5
Doc Al
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yes that is all the information that is in the question. I have previously calculated a maximum linear velocity
So there are other parts to this problem? Post the entire problem, start to finish.
 

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