Moment of Inertia - Need Guidance

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SUMMARY

The moment of inertia of a pendulum consisting of a rod and a thin cylindrical disk can be calculated using the parallel axis theorem. The moment of inertia for the rod about its center of mass is given by 1/12ML^2, where M is 4.9 kg and L is 3.3 m. The moment of inertia for the disk is 1/2MR^2, with M as 1.7 kg and R as 1.6 m. To find the total moment of inertia about the pivot point, the distances from the pivot to the center of mass of both components must be considered, applying the parallel axis theorem appropriately.

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  • Basic knowledge of physics concepts related to pendulums
  • Ability to perform algebraic calculations involving mass and distance
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A pendulum is made of a rod whose moment
of inertia about its center of mass is
1/12ML^2 where its mass is 4.9 kg and and its length
is 3.3 m, and a thin cylindrical disk, whose
moment of inertia about its center of mass
is 1/2MR^2, where its mass is 1.7 kg and its
radius is 1.6 m.

What is the moment of inertia of the pen-
dulum about the pivot point? Answer in units
of kg*m^2.

I tried adding the moment of Inertias --> ([1/12 (4.9) (3.3)^2 ]+[1/2 (1.7)(1.6)^2] = 6.62275.

This is obviously wrong. I have know clue how to approach this. I think there's a theorem (parallel theorem?) that will help but I don't know how to apply it. Help is much appreciated.
 
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The disc is at the END of the rod. Whats the distance of the disk from the pivot point then?
 

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