Question

does Anyone knows moment of inertia of semicircle about centre of mass?????

Answer 1

apply the theorem of the parallel axis and the distance between the centre of mass and centre is 2R/pi where R= radius,
 now
Icm=I0−M(2R/π)^2
and I0 = MR2
so  the moment of inertia about centre of mass of semicircle is
=MR^2[1−4/π^2]