(9) A physical pendulum consists of a meter stick (1 meter long) pivoted at a distance 20 cm(adsbygoogle = window.adsbygoogle || []).push({});

from one end and suspended freely. The frequency for small oscillation is closest to

(a) 0.67 Hz (b) 0.8 Hz (c) 1.1 Hz (d) 1.7 Hz (e) Insufficient information

(Hint: The moment of inertia of a stick of mass m and length L about its center of mass is mL2/12.)

Professor says the correct answer is (a) 0.67 Hz

I don't know what I do wrong on this question but I always get the frequency equal to .78Hz which is closer to .8Hz.

T = 2pi sqrt(I/(mgd)) I = moment of inertia

so T = 2pi sqrt((1/12)mL^2) / (mgL(1/5)))

T = 2pi sqrt(5L/12g)

T = 2pi sqrt(5/(12 * 9.8))

T = 1.29

f = 1/1.29 = .775

can someone tell me what im doing wrong?

Thanks

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# Homework Help: Physical Pendulum oscillation problem

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