Simple Harmonic Motion - what is its new period

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The discussion focuses on calculating the new period of a meter stick oscillating after being shortened from 1 m to 0.76 m. Initially, the period was 5 seconds, and the participant used the moment of inertia formula I = 1/12 mL^2 to find the spring constant k. After rebalancing and attempting to find the new period using the same equation, the participant encountered discrepancies in their calculations. They considered using the parallel axis theorem but concluded it was unnecessary since the oscillation occurs around the center of mass. Ultimately, they derived a new period of approximately 3.31 seconds, although they acknowledged potential errors in their calculations.
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A uniform meter stick is hung at its center from a thin wire. It is twisted and oscillates with a period of 5 s. The meter stick is then sawed off to a length of 0.76 m, rebalanced at its center, and set into oscillation.

what is its new period
I= 1/12 mL^2

equation: T= 2 pi * sqrt (I/k)
where T= 5
L= 1

I solved for K in terms of m (mass)...where i got k=7.599 m

then i replugged it into the same equation but where
T= unknown (trying to find)
L=.76

the mass cancels out and my answer gives me 3.8... which is wrong when i checked.

The only thing i can see is that I am using the wrong "I" for using the same equation 2nd time when i replugged it in. Should i be using the parallel axis theorem where

I= 1/12 mL^2 + Md^2
(since its not revolving around its center of mass)
L=1
d= .76

when i tried that i got my answer to be 6.28...wrong again
 

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The eqn for I for a rectangular plate is m(l^2+h^2)/12 where l and h are length and height respectively. It is revolving about the center of mass in both cases so no need for parallel axis theorum. You may need to solve for height, if the factor 0.76^3 isn't giving the right answer (remember the mass is being reduced by 24% as well).

BTW, neglecting the height, I got an answer of T=3.31s
 
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