Question 5
20 pts
A mass- spring- damper system is subjected to the periodic force shown. The mass of the system is m=10kg, the constant of the spring is 10000N/m and the constant of the damper is 500Ns/m. The period of the force is $\tau$ = 1 sec, and the amplitude A= 10N
(a)
If the Fourier transform approximation is given by:
$f(t) = \frac{A}{2} - \frac{A}{\pi} \sum_{j=1}^{\infty} (\frac{1}{j} \sin(\frac{2\pi j}{\tau} t))$
Therefore, the expansion considering four terms is given by:
$f(t) = \frac{A}{2} - \frac{A}{\pi} \sin(\frac{2\pi}{\tau} t) - \frac{A}{2\pi} \sin(\frac{4\pi}{\tau} t) - \frac{A}{3\pi} \sin(\frac{6\pi}{\tau} t)$
What is the maximum amplitude of the response corresponding to the four term of the Fourier approximation? Justify your answer.
O 0.500 mm
O 0.315 mm
O 0.151 mm
O 0.093 mm