Mass Moments of Inertia Example
Find the mass moment of inertia of a uniform slender rod about an axis through one end, perpendicular to the rod.
Concept
The mass moment of inertia measures resistance to angular acceleration. For a body rotating about an axis, where is the perpendicular distance from the axis to the mass element. For a uniform slender rod of mass and length , about an axis through one end (perpendicular to the rod): . About the center: . The parallel-axis theorem relates .
Notation: = mass moment of inertia, = mass, = length, = about center of mass, = distance between parallel axes.
Problem
A uniform slender rod has mass 6 kg and length 2 m. The axis of rotation is perpendicular to the rod and passes through one end of the rod.
Find:
- The mass moment of inertia of the rod about this axis.
Given
- Axis: through one end, perpendicular to rod
Mass moment of inertia about end
Final Answer
Mass moment of inertia about the end: .