Comparing Moment of Inertia of Wood and Iron Spheres

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The discussion centers on comparing the moment of inertia of wooden and iron spheres of the same diameter. It highlights that the moment of inertia formula for a solid sphere is I = (2/5)mr^2. Since the iron sphere has a greater mass, it is concluded that it will have a larger moment of inertia compared to the wooden sphere. Specifically, if the mass of the iron sphere is twice that of the wooden sphere, the moment of inertia for the iron sphere is indeed greater. This confirms that mass directly influences the moment of inertia for spheres of equal radius.
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Sir,
1) Consider two spherical balls one made of wood and other made of iron having the same diametre. Which one has greater moment of inertia about their centre of gravity?
 
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The formula for any solid sphere is
I=\frac{2}{5}mr^2
 
Sir,
My doubt is - For a given radius, the iron sphere having a greater mass should have larger moment of inertia, isn't it?Suppose mass of iron sphere is twice the mass of wooden sphere. In that case,
Moment of inertia of wooden ball = 2/5(MR^2)
Moment of inertia of iron ball = 2/5(2MR^2)
Here the symbol "^" represents power.
 
You got your answer...
 

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