Moment of inertia for an irregular shaped object

In summary, the moment of inertia of an irregular shaped object with mass 2.45 kg and a moment of inertia of 5.782 kgm2 about an axis through a point 1.40 m from its center of mass can be calculated using the parallel axis theorem. The moment of inertia about a parallel axis through its center of mass (I) can be found by adding the moment of inertia about the centroid (I_c) to the product of the mass (M) and the square of the distance from the center of mass (h^2). However, in the given conversation, the individual is incorrectly using the formula and is reminded to calculate I_c instead of using the given value.
  • #1
Punchlinegirl
224
0
An irregular shaped object of mass 2.45 kg has a moment of inertia 5.782 kgm2 about an axis through a point 1.40 m from its center of mass. Calculate the moment of inertia about a parallel axis through its center of mass.

I used the parallel axis theorem,
I= I_c + Mh^2
I= 5.782 +(2.45)(1.40)^2
I= 10.6 kgm^2

This wasn't right.. can someone tell me what I'm doing wrong. Thanks
 
Physics news on Phys.org
  • #2
You are asked for the moment of inertia about the centroid, yet you are calculating the moment of inertia about a parallel axis to the centroid axis...
 
  • #3
I_c is not 5.782, I_C is what your solving for.

I just got beaten to it. Have fun cyclovenom, I am going back to learning matlab.
 
  • #4
ok I got it.. thanks
 

1. What is moment of inertia for an irregular shaped object?

Moment of inertia for an irregular shaped object is a measure of its resistance to rotational motion. It takes into account the distribution of mass around the axis of rotation.

2. How is moment of inertia calculated for an irregular shaped object?

Moment of inertia for an irregular shaped object is calculated by breaking down the object into smaller, simpler shapes and using the formula for moment of inertia for each shape. These individual moments of inertia are then added together to get the total moment of inertia for the object.

3. Why is moment of inertia important for an irregular shaped object?

Moment of inertia is important for an irregular shaped object because it affects how the object will respond to rotational forces. It can also determine the stability and strength of the object.

4. How does the shape of an object affect its moment of inertia?

The shape of an object can greatly affect its moment of inertia. Objects with more mass located further away from the axis of rotation will have a higher moment of inertia compared to objects with the same mass but located closer to the axis of rotation.

5. Can the moment of inertia for an irregular shaped object be changed?

Yes, the moment of inertia for an irregular shaped object can be changed by altering the distribution of mass around the axis of rotation. This can be achieved by changing the shape or adding/removing mass from the object.

Similar threads

  • Introductory Physics Homework Help
Replies
11
Views
1K
  • Introductory Physics Homework Help
Replies
2
Views
614
Replies
25
Views
441
  • Introductory Physics Homework Help
Replies
28
Views
533
  • Introductory Physics Homework Help
2
Replies
40
Views
2K
  • Introductory Physics Homework Help
Replies
13
Views
1K
  • Introductory Physics Homework Help
Replies
5
Views
2K
  • Introductory Physics Homework Help
Replies
21
Views
1K
  • Introductory Physics Homework Help
Replies
12
Views
944
  • Introductory Physics Homework Help
Replies
4
Views
945
Back
Top