MOMENT OF INERTIA OF A RECTANGLE 288 



Example 2. For the given section find the greatest and least 

 moments of inertia. Draw the momental ellipse for the section 

 and use it to find the moment of inertia about the axis OR. 



Y! 



I T 



67 



i 1 



1058 



/ 

 /' 

 / 



403OH 



I 

 FIG. 63. 



= 5-342 = Q 



= 63-48 = P 



The area of the section = 5-75 



~5-75 



and 



P = 



= 



63-48 



= 0-301 



5-342 



1-038 



Also 



*v7*i 

 0-445, I, . = ^r, - 29-03 



