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

In this experiment a physical pendulum consisting of a rod and two large rubber stoppers (on top of each other) is swung from a point 1 mm from the end point. Calculate the moment of inertia of the pendulum about the point of suspension?

Data:

m=mass of rod=97.1 g

M=mass of the stoppers and the bolt=200 g

L=1 meter=length of rod

d=distance between the center of mass (CM) of the rod and the point of suspension=499 mm

D=distance between the center of mass of the stoppers and the Point of suspension=879 mm

R=distance between the Center of Mass of the rod-stopper system and the point of suspension=689 mm

theta (max)=the max angular displacement of the system from equilibrium (i.e. the max angular amplitude). Remember, theta (max) should be less than about pi/12 radian for the motion to be simple harmonic)=90 degrees

T(sub e)=the experimental period of oscillation of the pendulum. (measure and record at least three sets of 10 complete oscillations)=17.39 seconds/10 oscillations.

r=the distance from the center of the ruler to the point of rotation (.499 m)

2. Relevant equations

Note: I was sick when my teacher taught this so I learned the following from a friend.

use parallel axis theorem+MOI of point masses

(I)totalrod = (I)ruler + (I)mass

(I)mass= MR^2 where R = the distance from the center of the point mass to the rotation

and M is the mass for the point mass (200 g)

(I)ruler is the parralel axis theorem which is like

(I)ruler= (I)centerofmass + Md^2

where (I)center of mass is equal to 1/3Mr^2 where r is the distance from the center of the ruler to the point of rotation (.5 meters) + Md^2...

3. The attempt at a solution

I was sick...I dunno Sorry!

Help..eh :)

Thanks so much! This is due tomorrow so Urgency is somewhat required LOL...I wish I was smart

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# Homework Help: How do I find the Moment of Inertia?

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