(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

The moment of inertia for an arm or leg can be expressed as I = AmL^2, where A is a unitless number that depends on the axis of rotation and the geometry of the limb and L is the distance from the center of mass. Say that a person has arms that are 31.30 cm in length and legs that are 40.69 cm in length and that both sets of limbs swing with a period of 1.20 s. Assume that the mass is distributed uniformly in both the arms and legs.

Calculate the value of A for the person's arms.

L arm = .313 m

T = 1.20

2. Relevant equations

A = (g/L) (T/2pi)^2

3. The attempt at a solution

(9.8/.313) (1.20/2pi)^2 = 1.142

I'm not sure where I'm going wrong with this problem. After the derivation of the equation it's plug and chug. I looked up the equation I derived and it's correct. Can anyone lend me a hand?

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# Homework Help: Calculating the A value of a physical pendulum

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