Calculating Moment of Inertia for a Curved Rod with Respect to a Specific Axis

AI Thread Summary
To calculate the moment of inertia for a thin, homogeneous curved rod with radius of curvature R about the axis through its center of mass, the parallel and perpendicular axis theorems are essential tools. The discussion suggests first determining the moment of inertia about a more accessible axis, possibly I_{Oz}, and then converting it to I_{x} using the perpendicular axis theorem. Afterward, the moment of inertia can be adjusted to the desired axis using the parallel axis theorem, noting that this involves subtracting the term related to the mass and distance from the center of mass. The location of the center of mass G is crucial for these calculations. Ultimately, these methods provide a systematic approach to finding the moment of inertia for complex shapes.
Iqish
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Homework Statement
A thin, homogeneous, curved rod with
the radius of curvature 𝑅 and mass π‘š are in
π‘₯𝑦 plane. Determine the moment of inertia,
𝐼π‘₯'π‘₯ ', with respect to the π‘₯ 'axis, which goes
through the body's center of mass G
Relevant Equations
Steiners sats:𝐼π‘₯π‘₯ = 𝐼π‘₯β€²π‘₯β€² + π‘šπ‘¦^2𝐺
Given:Thin, homogeneous, curved rod with radius of curvature 𝑅 See figure to the down.
7m2HF.png

Find: The moment of inertia 𝐼π‘₯β€²π‘₯ β€² with respect to π‘₯β€²- the axis passing through the center of mass (point 𝐺).
Can someone who can help me ?
 
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Iqish said:
Homework Statement:: A thin, homogeneous, curved rod with
the radius of curvature 𝑅 and mass π‘š are in
π‘₯𝑦 plane. Determine the moment of inertia,
𝐼π‘₯'π‘₯ ', with respect to the π‘₯ 'axis, which goes
through the body's center of mass G
Relevant Equations:: Steiners sats:𝐼π‘₯π‘₯ = 𝐼π‘₯β€²π‘₯β€² + π‘šπ‘¦^2𝐺

Given:Thin, homogeneous, curved rod with radius of curvature 𝑅 See figure to the down.
View attachment 258878
Find: The moment of inertia 𝐼π‘₯β€²π‘₯ β€² with respect to π‘₯β€²- the axis passing through the center of mass (point 𝐺).
Can someone who can help me ?

Have you learned about the parallel and perpendicular axis theorems?

Just an initial thought that I have on this. So it looks quite difficult to actually calculate the moment of inertia about the required axis, so it suggests to me that we will be shifting it to that axis (via parallel axis theorem). Perhaps, we can find I_{Oz} (out of the page) , turn that into I_{x} via perpendicular axis theorem and then shift it to the required axis (would require us to know the location of G, but that seems easier to find than calculating about that axis. Otherwise, maybe we find I_{x} and then shift?

(Note, we would be 'reverse' shifting it as the parallel axis theorem is defined for an axis relative to centroid axis, would just mean that we subtract the m d^2, rather than add it)
 
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