Finding the period of a pendulum witha string that has mass

AI Thread Summary
The discussion focuses on deriving the period of a pendulum with a massy string and a non-point mass bob, treating the string as a rigid rod. Participants reference the theoretical moment of inertia for a long thin rod, which is 1/12 mL^2, to aid in calculations. An attempt at a solution is shared, but there is uncertainty about its correctness. The importance of ensuring the derived equation aligns with the known case of a massless string and point-mass bob is emphasized. The conversation highlights the complexities introduced by considering the mass of the string in pendulum dynamics.
Physics Man
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1. The problem statement, all variables and gihttps://www.physicsforums.com/attachments/218400 ven/known data
Assuming the string from a simple pendulum did not have negligible mass and the pendulum bob was not a point mass, then determine an expression for the period of a single small-amplitude oscillation, treating the string as a rigid rod.

Homework Equations


Theoretical moment of inertia of center of mass for long thin rod = 1/12 mL^2

The Attempt at a Solution


https://prnt.sc/i02al1 This is what I did but I don't think that it is right

jODFzxuTTEim-4LYVRrYeA.jpg
 

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Physics Man said:
This is what I did but I don't think that it is right
Why not? Check if your equation reduces to the limiting case for which you know the answer, namely massless string and point-mass bob.
 
Physics Man said:
solved
Please do not delete the post that initiated the thread.
 
Thread 'Collision of a bullet on a rod-string system: query'
In this question, I have a question. I am NOT trying to solve it, but it is just a conceptual question. Consider the point on the rod, which connects the string and the rod. My question: just before and after the collision, is ANGULAR momentum CONSERVED about this point? Lets call the point which connects the string and rod as P. Why am I asking this? : it is clear from the scenario that the point of concern, which connects the string and the rod, moves in a circular path due to the string...
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