Moment of inertia - displaced axis

AI Thread Summary
To calculate the moment of inertia for a system of three cylinders with a displaced axis, the parallel axis theorem is essential. The user successfully identified the distance from the center of mass to the revolving axis, which is a crucial step. The discussion highlights the challenge of calculating moment of inertia when the axis does not align with the object's center or surface. Utilizing the parallel axis theorem allows for the adjustment of the moment of inertia based on this distance. This approach effectively resolves the user's query regarding the displaced axis.
finitefemmet
Messages
13
Reaction score
0
Hi,

I need some help, I have a system with 3 cylinders (I got the center of mass for the system). Now I need to calculate the moment of inertia for the system.

I have tried to find some examples or general information, but they all show when the axis either is centered within the object or on the surface. This problem has a distance from the system and is not "touching" any surfaces. I figured out distance from the center of mass too the revolving axis. But I can't get my head around how I can solve this with the "displaced" axis so to speak.

Greatfull for every answer,

thanks!
 
Physics news on Phys.org
That did the trick;)
 
I multiplied the values first without the error limit. Got 19.38. rounded it off to 2 significant figures since the given data has 2 significant figures. So = 19. For error I used the above formula. It comes out about 1.48. Now my question is. Should I write the answer as 19±1.5 (rounding 1.48 to 2 significant figures) OR should I write it as 19±1. So in short, should the error have same number of significant figures as the mean value or should it have the same number of decimal places as...
Thread 'A cylinder connected to a hanging mass'
Let's declare that for the cylinder, mass = M = 10 kg Radius = R = 4 m For the wall and the floor, Friction coeff = ##\mu## = 0.5 For the hanging mass, mass = m = 11 kg First, we divide the force according to their respective plane (x and y thing, correct me if I'm wrong) and according to which, cylinder or the hanging mass, they're working on. Force on the hanging mass $$mg - T = ma$$ Force(Cylinder) on y $$N_f + f_w - Mg = 0$$ Force(Cylinder) on x $$T + f_f - N_w = Ma$$ There's also...
Back
Top