Question 6.P.9: An accelerometer has a natural frequency of 40 rad/s and a d...

Dynamics of Structures

An accelerometer has a natural frequency of $40 \mathrm{rad} / \mathrm{s}$ and a damping ratio of $0.6$ . It is calibrated to read correctly the input acceleration at very low frequencies. Find the calibration factor. An input signal given by $\ddot{u}_{g}=4 \sin (4 \pi t)+3 \sin (5 \pi t) \mathrm{m} / \mathrm{s}^{2}$ is supplied to the accelerometer. Plot the output signal produced by the instrument. What are the measured amplitudes of the two components of the given signal.

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