Physics
Mechanics
Easy
Question
A ring of mass M and radius R lies in x-y plane with its centre at origin as shown. The mass distribution of ring is non uniform such that , at any point P on the ring , the mass per unit length is given by 
(where 
is a positive constant). Then the moment of inertia of the ring about z-axis is :
The correct answer is:
Divide the ring into infinitely small lengths of mass dmi .Even though mass distribution is non-uniform, each mass dmi is at same distance R from origin.
MI of ring about z-axis is
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