Question

Radius of gyration of uniform thin rod of lenght L about an axis assing normally through its centre of mass is:

• A. $\frac { \mathrm { L } } { \sqrt { 12 } }$
• B.
• C.
• D. 12L.

Answer 1

Answer: (A)

$\frac { \mathrm { L } } { \sqrt { 12 } }$

Answer 2

$\frac { \mathrm { ML } ^ { 2 } } { 12 } = \mathrm { MK } ^ { 2 } \Rightarrow \mathrm {~K} = \frac { \mathrm { L } } { \sqrt { 12 } }$