Question

Two rods of equal length and equal mass are kept along x and y axis respectively find moment of inertia along x=y

Answer 1

Moment of Moment of inertia of a rod of about an axis passing through centre and perpendicular to length:

I=Ml²/12

Moment of inertia of the rod about an axis inclined an angle theta to the original axis:

I'=I sin²θ

The line x=y makes an angle of 45 degrees x and y axes.

Hence,

I' = I sin²45= I/2

Moment of inertia of both rods about the line passing through x=y:

two rods= 2(I2) =I = (Ml²/12)

Hope you understand!!