List the reasons why we never see infinite amplitude resonant vibrations in the
world.
? There is always damping.
? The linear vibration theory fails when the amplitude is large enough. Therefore the
prediction of infinite amplitude is not true.
? Materials would fail when the amplitude of vibration is large enough.
? Engineers don't like large amplitude vibrations.
When a uniform circular disc is supported at the center, does it swing freely like a
pendulum?
? No.
? Yes.
? Maybe, depending on initial conditions
To expand a periodic function f(t)=f(t+T) of period T in Fourier series, we use the
frequency omega =2?/T as the fundamental frequency, because it is
? The slowest frequency in f(t)
? The fastest frequency in f(t)
? The middle frequency in f(t)
