Question

The radius of gyration of an uniform rod of length l about an axis passing through one of its ends and perpendicular to its length is

• A. $\frac { 1 } { \sqrt { 2 } }$
• B. $\frac { 1 } { 3 }$
• C. $\frac { 1 } { \sqrt { 3 } }$
• D. $\frac { 1 } { 2 }$

Answer 1

Answer: (C)

$\frac { 1 } { \sqrt { 3 } }$

Answer 2

Moment of inertia of rod of mass M and length l about its axis passing through one of its ends and perpendicular to it is.

As: $\mathrm { I } = \mathrm { Mk } ^ { 2 }$ where k is the radius of the gyration $\therefore \mathrm { Mk } ^ { 2 } = \frac { 1 } { 3 } \mathrm { Ml } ^ { 2 }$ or