From a uniform circular disc of radius R and mass 9 M, a small disc of radius is removed as shown in the figure. The moment of inertia of the remaining disc about an axis perpendicular to the plane of the disc and passing through centre of disc is :
4 MR2
10 MR2
As we learnt that
Moment of inertia for disc -
- wherein
About an axis perpendicular to the plane of disc & passing through its centre .
Perpendicular Axis theorem -
(for a body in XY plane )
- wherein
= moment of inertia about z axis
. :moment of inertia about x & y axis in the plane of body respectively.
Option 1)
This is incorrect
Option 2)
4 MR2
This is correct
Option 3)
This is incorrect
Option 4)
10 MR2
This is incorrect
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