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JEE Main20257 Apr 2025Morning ShiftPhysicsRotational MotionActual

A , B and C are disc, solid sphere and spherical shell respectively with same radii and masses. These masses are placed as shown in figure. The moment of inertia of the given system about P Q is X 15 I , where I is the moment of inertia of the disc about its diameter. The value of x is _______.

Correct answer

0

Step-by-step solution

All bodies have same mass and same radius. A Disc B Solid sphere C Spherical shell and, I = MR ^2 4 I _ PQ = MR ^2 4 + ( 2 5 MR ^2+ MR ^2 )+ ( 2 3 MR ^2+ MR ^2 ) I _ PQ = 15 MR ^2+24 MR ^2+60 MR ^2+40 MR ^2+60 MR ^2 60 I _ PQ = 199 60 MR ^2= 199 15 ( MR ^2 4 ) = 199 15 I

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