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

Find the ratio of radii of gyration of a circular disc and a circular ring of same mass and radius, about an axis passing through their centre and perpendicular to their planes.

A
1:2
Right on! Give the BNAT exam to get a 100% scholarship for BYJUS courses
B
3:2
No worries! We‘ve got your back. Try BYJU‘S free classes today!
C
2:1
No worries! We‘ve got your back. Try BYJU‘S free classes today!
D
2:1
No worries! We‘ve got your back. Try BYJU‘S free classes today!
Open in App
Solution

The correct option is A 1:2
Let m and r be the mass and radius of the ring and disc respectively.
Moment of inertia of ring about an axis passing through its centre and perpendicular to its plane:
Iring=mr2

Moment of inertia of disc about an axis passing through its centre and perpendicular to its plane:
Idisc=mr22
Since, I=mK2 where, K is radius of gyration about the given axis.
Kring=Iringm=r
Kdisc=Idiscm=r2
KdiscKring=12
Kdisc:Kring=1:2

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