Why Is My Physical Pendulum Period Calculation Incorrect?

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SUMMARY

The discussion centers on the incorrect calculation of the period (T) of a physical pendulum. The formula used, T = sqrt(mgL/I), was incorrectly applied with the inertia (I) calculated as 1/3(m/2)L^2 + (m/2)L^2. The correct expression for the period is T = 2π√(Iθ/τ), and the center of mass must be accurately determined, which is at L/2 for a uniform rod. The miscalculation stems from improper application of the inertia and torque concepts.

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Homework Statement


upload_2018-3-1_0-8-36.png


Homework Equations


T = sqrt(mgL/I)

The Attempt at a Solution


my calculated Inertia (I) = 1/3(m/2)L^2 + (m/2)L^2
my distance (d) = L/2
m is just total mass

so, T = 2pi * sqrt(mgd/I) = 2pi sqrt(4L/(3g)) which is wrong :(
 

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The time period is Given by: $$ T = 2\pi \sqrt{ \frac { I \theta } { \tau } }$$
Also Where is the Center of mass? Are you sure it is at ##\frac {L} {2}##. Take the torque about that.
 

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