Question

For the given uniform square lamina $ABCD$, whose centre is $O$

• A. $\sqrt{2} I_{A C}=I_{E F}$
• B. $I_{A D}=3 I_{E F}$
• C. $I_{A C}=I_{E F}$
• D. $I_{A C}=\sqrt{2} I_{E F}$

Answer 1

Answer: (C)

$I_{A C}=I_{E F}$

Answer 2

Let the each side of square lamina is $d$. So, $I_{E F}=I_{G H}$ (due to symmetry) and $I_{A C}=I_{B D}$ (due to symmetry) and $I_{A C}=I_{B D}$ (due to symmetry) Now, according to theorem of perpendicular axis,