Moment of Inertia: Easier Way to Determine Formula

AI Thread Summary
Determining the correct formula for calculating moment of inertia can be challenging, especially when distinguishing between different shapes like hoops and cylinders. The key is to identify the axis of rotation specified in the problem, as this influences the formula to use, such as MR^2 for a hoop and (1/2)MR^2 for a solid cylinder. Understanding theorems like Steiner's theorem and the use of integral calculus can also aid in solving these problems. Having a clear grasp of the definitions and properties of the objects in question is essential. Familiarity with these concepts will streamline the process of selecting the appropriate formula.
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does anyone know an easier way to determine which formula is used for calculating moment of inertia? i have all the formulas and descriptions, but i have trouble figuring out which formula to use based on what is given in the problem. any ideas thatll help me?
 
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If you have all the formulas,what are you asking for...?The expression for the tensor of inertia...?The definition of axial moment of inertia:
I_{O}=:\int r^{2} \ dm

,or what...?

Daniel.
 
What formulas do you mean?
 
I mainly need to know how to determine the axis, and the difference between a hoop and a cylinder...mainly, (MR^2) and (1/2 MR^2)
 
You're usually told which axis you rotate the object about.And yes,there are 2 more things:the theorem of Steiner and the integral calculus...
Are u familiar with them ?

Daniel.
 

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