Ratio of radius of gyration of a hollow sphere to that of a solid cylinder of equal mass, for moment of Inertia about their diameter axis AB as shown in figure is 8/x. The value of x is : [figure]
- 34
- 51
- 67
- 17
Answer
(3) 67
Solution
Hollow sphere (about a diameter): Mk12 = 23MR2 k12 = 23R2
Solid cylinder (radius R, length l = 4R) about the diameter of its end face:
I = MR24 + Ml23
= MR24 + 16MR23 = 6712MR2
k22 = 6712R2
k1k2 = 23 1267 = 867 x = 67
Answer: (3)