Definition of Parallel-axis theorem

  • Context: Undergrad 
  • Thread starter Thread starter Duane
  • Start date Start date
  • Tags Tags
    Definition Theorem
Join the discussion
Ask a follow-up here, or get your own question answered by working scientists, mathematicians and engineers — people, not an autocomplete.
Real named experts · corrections over time · the nuance an AI answer skips
3 replies · 5K views
Duane
Messages
8
Reaction score
0
What is the physical meaning of each term in the parallel-axis theorem?


I=I com +Mh^2
 
Physics news on Phys.org
Duane said:
What is the physical meaning of each term in the parallel-axis theorem?


I=I com +Mh^2
Not sure what you mean by 'physical' meaning, but:
I = moment of inertia about some axis a distance 'h' from the center of mass
Icom = moment of inertia about some axis (parallel to the other) passing through the center of mass
M = mass of object
h = distance between those two parallel axes

You can think of it as the sum of the moment of inertia about the center of mass and the moment of inertia of the total mass (considered as a point mass) about the axis in question.
 
Duane said:
What is the physical meaning of each term in the parallel-axis theorem?


I=I com +Mh^2
Icom is the moment of inertia of an object about an axis through the centre of mass. I is the moment of inertia of the object about an axis that is parallel to the axis through the centre of mass (com) and separated from it by a distance h. M is the mass of the object.

AM
 
Thanks, that helped a lot!