What Is Moment of Inertia in Rotational Motion?

AI Thread Summary
Moment of inertia, or rotational inertia, differs from linear inertia as it depends not only on mass but also on the distance of each mass element from the axis of rotation. This relationship means that calculating moment of inertia involves calculus, taking into account both mass and its distribution. In cases with symmetrical shapes, these calculations can often be simplified into algebraic formulas. Understanding moment of inertia is crucial for analyzing rotational motion and dynamics. Overall, it highlights the complexity of rotational systems compared to linear motion.
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please help me to understand moment of inertia
 
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With linear motion, the inertia, the tendency to resist being accelerated, is simply the mass. Not so with rotational motion. Rotational inertia (moment of inertia is another name for it) is based on the mass and also how far each bit of mass is from the axis of rotation. So instead of inertia just being mass, it's a calculus expression involving mass and distance. For problems with a lot of symmetry, the calculus simplifies to algebraic formulas.
 


mikelepore said:
With linear motion, the inertia, the tendency to resist being accelerated, is simply the mass. Not so with rotational motion. Rotational inertia (moment of inertia is another name for it) is based on the mass and also how far each bit of mass is from the axis of rotation. So instead of inertia just being mass, it's a calculus expression involving mass and distance. For problems with a lot of symmetry, the calculus simplifies to algebraic formulas.

Thanks
 

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