1
For the adjoining diagram (a uniform right-angled triangular plate ABC), the correct relation between I1, I2 and I3 is (I – moment of inertia about the marked side) [figure]
- I1 > I2
- I2 > I1
- I3 > I1
- I3 > I2
Answer
(2) I2 > I1
Solution
For a uniform triangular plate, the moment of inertia about one side is Mh26, where h is the distance of the opposite vertex from that side.
About AB (h = BC = 3): I1 = 9M6 = 1.5M
About BC (h = AB = 4): I2 = 16M6 2.67M
About CA (h = AB BCCA = 125 = 2.4): I3 = (2.4)2 M6 = 0.96M
I2 > I1 > I3
Answer: (2)
AIPMT 2000