BITSAT 2019 Slot 2 Solved Paper

The moment of inertia of disc of radius R about its axis is
I=

M′R2

2

where, M′= mass of complete disc
=2M
∴I=

2MR2

2

I=MR2 .......(i)
If I1 be the moment of inertia of semicircular disc about its axis, then disc may be assumed as combination of two semi-circular parts, Thus, I=I1+I1⇒I1=

I

2

=

MR2

2