Rotational kinetic energy of a wheel

AI Thread Summary
To calculate the maximum rotational kinetic energy of a wheel with a diameter of 1.4m, a radius of gyration of 0.42m, and a mass of 13kg, the moment of inertia is first determined as 2.29 kg/m². However, the calculation requires the angular velocity, which is not provided in the problem statement. Without additional information, such as the number of turns or the maximum linear velocity, it is challenging to proceed with the kinetic energy calculation. The discussion emphasizes the need for complete problem details to solve for rotational kinetic energy accurately. Therefore, presenting the full problem is essential for further assistance.
richyr33
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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
 
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richyr33 said:
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?
 
You have to know how many turns it took so you can use: \frac{1}{2}J_{\Delta}\omega^{2}=M_{\Delta}*\Delta\theta to calculate the maximal angular speed.

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

Ps: JΔ of a wheel : J_{\Delta}=M*R^{2}
 
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.
 
richyr33 said:
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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