A thin circular ring of mass M and radius R is rotating with a constant angular velocity 2 rads$-$1 in a horizontal plane about an axis vertical to its plane and passing through the center of the ring. If two objects each of mass m be attached gently to the opposite ends of a diameter of ring, the ring will then rotate with an angular velocity (in rads$-$1).
Solution
<p>${I_1}{\omega _1} = {I_2}{\omega _2}$</p>
<p>$M{R^2}{\omega _1} = (M{R^2} + 2m{R^2}){\omega _2}$</p>
<p>${\omega _2} = \left( {{M \over {M + 2m}}} \right){\omega _1}$</p>
<p>${\omega _2} = 2\left( {{M \over {M + 2m}}} \right)$</p>
About this question
Subject: Physics · Chapter: Rotational Motion · Topic: Centre of Mass
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