Question

Two masses each of mass M are attached to the end of a rigid massless rod of length L. The moment of inertia of the system about an axis passing centre of mass and perpendicular to its length is

• A. $\frac { \mathrm { ML } ^ { 2 } } { 4 }$
• B. $\frac { \mathrm { ML } ^ { 2 } } { 2 }$
• C.
• D. $2 \mathrm { ML } ^ { 2 }$

Answer 1

Answer: (B)

$\frac { \mathrm { ML } ^ { 2 } } { 2 }$

Answer 2

The moment of inertia of the system about the given axis is.

$\mathrm { I } = \mathrm { M } \left( \frac { \mathrm { L } } { 2 } \right) ^ { 2 } + \mathrm { M } \left( \frac { \mathrm { L } } { 2 } \right) ^ { 2 } = \frac { \mathrm { ML } ^ { 2 } } { 4 } + \frac { \mathrm { ML } ^ { 2 } } { 4 } = \frac { \mathrm { ML } ^ { 2 } } { 2 }$