(20%) The sensor with natural frequency 800 Hz is a second order system. Its damping ratio $=0.14. The sensor was tested

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20 The Sensor With Natural Frequency 800 Hz Is A Second Order System Its Damping Ratio 0 14 The Sensor Was Tested 1 (24.63 KiB) Viewed 25 times

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(20%) The sensor with natural frequency 800 Hz is a second order system. Its damping ratio $=0.14. The sensor was tested by a sinusoidal force with a frequency of 400Hz. 1) How much are the amplitude ratio of A(w) and phase angle (m)? 2) If the damping ratio becomes the value of 0.7, what is the changes A(w) and phase angle o(a)? 3) If the amplitude errors are required to be less than 5%, what are the measurable frequency range? 4) If the damping ratio has varied, the phase difference between the input and the output signal become to be 45° when the sensor is used to measure a signal with a frequency of 2400Hz. What is the current damping ratio?