A more direct approach in determining moment of inertia?

AI Thread Summary
The discussion focuses on understanding the moment of inertia without delving into calculus, emphasizing the constant values for different shapes, such as 2/5 for a sphere and 1/2 for a cylinder. It highlights that the moment of inertia (I) decreases when mass is closer to the axis of rotation. While mnemonics are suggested for remembering these constants, the conversation concludes that there are no shortcuts or tricks involved. The parallel axis theorem is mentioned as a helpful tool for translating moment of inertia to a parallel axis. Overall, the thread aims to simplify the concept of moment of inertia for easier comprehension.
bluejay27
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is there a directly knowing the moment if the moment of inertia would be lower for an object? I am emphasizing on knowing the value of the constant value. For a sphere is 2/5 and for a cylinder 1/2, this constant values will be placed at c of cMR^2 without directly going into calculus. A mnemonic perhaps?
 
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I take it you know the definition of ##I##, the moment of inertia ? The closer the massive stuff is to the axis, the lower ##I##. And that's about it. You can go through the list and conclude for yourself there's no tricks or mnemonics.
The parallel axis theorem can be useful to translate to another (parallel) axis.
 
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