A rod of linear mass density 'λ' and length 'L' is bent to form a ring of radius 'R'. Moment of inertia of ring about any of its diameter is.
Solution
<p>First, relate the length of the rod to the circumference of the ring:</p>
<p>$ L = 2\pi R $</p>
<p>The mass of the ring, denoted by $ M $, is the product of the linear mass density and the length of the rod:</p>
<p>$ M = \lambda \times L $</p>
<p>The moment of inertia of a ring about a diameter is given by the formula:</p>
<p>$ I = \frac{MR^2}{2} $</p>
<p>Substituting the expression for mass $ M $ and using the relation for $ R $ derived from the circumference:</p>
<p>$ I = \frac{\lambda \times L}{2} \times \left(\frac{L}{2\pi}\right)^2 $</p>
<p>Simplifying the expression, we arrive at:</p>
<p>$ I = \frac{\lambda L^3}{8\pi^2} $</p>
<p>This is the moment of inertia of the ring about any of its diameters.</p>
About this question
Subject: Physics · Chapter: Rotational Motion · Topic: Centre of Mass
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