Question

An isosceles triangular piece is cut from a square plate of side l. The piece is one-fourth of the
square and mass of the remaining plate is M. The moment of inertia of the plate about an axis
passing through O and perpendicular to its plane is​

Answer 1

let axis of rotation pass through hypotenuse. considering rotation about hypotenuse u will see ki triange ke do partts se ek square ban jayege and hypotenuse square ka diagonal hoga.

we know square ke daigomal se pass axis ka mi=ml^2/6if mass of sq is m

now triangle ka mass sq ke mass ka half hoga to  

mi abt hypotenuse =ml^2/12  

now apply perpendicular axis thm  

mi about base as well as perp is ml^2/24