wiz-icon
MyQuestionIcon
MyQuestionIcon
1
You visited us 1 times! Enjoying our articles? Unlock Full Access!
Question

The moment of inertia of a rod of length l about an axis passing through its centre of mass and perpendicular to the rod is I. The moment of inertia of hexagonal shape formed by six such rods, about an axis passing through its centre of mass and perpendicular to its plane will be

A
16I
No worries! We‘ve got your back. Try BYJU‘S free classes today!
B
40I
No worries! We‘ve got your back. Try BYJU‘S free classes today!
C
60I
Right on! Give the BNAT exam to get a 100% scholarship for BYJUS courses
D
80I
No worries! We‘ve got your back. Try BYJU‘S free classes today!
Open in App
Solution

The correct option is C 60I
Moment of inertia of rod AB about its centre and perpendicular to the length I=ml212
ml2=12I
Now moment of inertia of the rod about the axis which is passing through O and perpendicular to the plane of hexagon
Irod=ml212+mx2
[From the theorem of parallel axes]


=ml212+m(32l)2=5ml26
So, total moment of inertia of system,
Isystem=6×Irod=6×5ml26=5ml2
Isystem=5(12I)=60I
[As ml2=12I]

flag
Suggest Corrections
thumbs-up
0
Join BYJU'S Learning Program
Join BYJU'S Learning Program
CrossIcon