Moment of inertia

[eksdee]

Can somebody help me on this? I don't know why I can't get the answer and I don't think I used a wrong method

 

[Deleted member 4993]

Can somebody help me on this? I don't know why I can't get the answer and I don't think I used a wrong method

Please share your work with us - showing steps and answer - so that we can point out where you went wrong!

 

[eksdee]

Here's my workings thanks

 

[Deleted member 4993]

View attachment 12289
Here's my workings thanks

You can apply parallel axis theorem to move axis of rotation - ONLY - from (or to) CENTROID of a body to another point.

So the MIs of the four rods are incorrect. That should be:

4*(3/2*m)*[1/12*(2a)^2 + (2a)^2]

 

[eksdee]

Alright thanks a lot ?