The radius of gyration of a ring about the tangent perpendicular to its plane is……………

Options

A. `sqrt(3):sqrt(2)`
B. `1:sqrt(2)`
C. `sqrt(2):1`
D. `sqrt(2):sqrt(3)`

Answer

B

Explanation

Radius of gyration of a circular disc `k_(d)=(R )/(sqrt(2))`
Radius of gyration of a ring `k_(R )=R`
both having same mass and radius
`therefore (k_(d))/(k_(R))=((R)/sqrt(2))/(R)=(1)/(sqrt(2))`
`therefore k_(d):k_(R)=1:sqrt(2)`