Question

Determine the moment of inertia of circular disc about its diameter

Answer 1

According to perpendicular axis theorem..
I(x) + I(y) = I(z)
2×I = MR²/2 ( Moment of inertia about x axis
and y axis would be same)
I = MR²/4

Hence momnet of inertia about diameter is
MR²/4

here I represents Moment of inertia

Answer 2

$\textbf{Answer is in attachment!}$