- #1
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Homework Statement
A pendulum is constructed using a thin rod (m1 = 2.0 kg, L = 1.0m) and a uniform sphere (m2 = 1.0 kg, R = 0.50 m). The period in "s" for small oscillations is:
a) 1.5
b) 1.7
c) 2.0
d) 2.2
e) 2.5
Homework Equations
T = 2pi *sqrt(I/mgd)
The Attempt at a Solution
To start off, the rod is pivoting at an end attached to a ceiling with the sphere attached to its bottom.
I initially got (c) by assuming it was a simple pendulum ("thin rod", lol), but a more careful look reveals that the rod does not have negligible mass, and so this pendulum must be physical. My biggest dilemma with this problem is finding the center of mass for this system, and then finding "d" assuming that. Unfortunately, inertia is my weakest area in Physics, and so I am stuck as to how to use the parallel axis theorem correctly to get my answer.
Any hints?
If it helps, people in my class keep getting (d) or (e).