Question

Problem 14.43 Enhanced - with Feedback What is the frequency of oscillations? The common field cricket makes its characteristic loud chirping sound using a specialized vibrating structure in its wings. The motion of this structure-and the sound intensity that it produces--can be modeled as a damped oscillation. The sound intensity of such a cricket is shown in(Figure 1) Express your answer with the appropriate units. f 5.0 kHz Previous Answers Figure < 10f1 > Correct Part B Intensity What is the time constant for the decay of these oscillations? Express your answer with the appropriate units The plot shows the intensity as a function of time. The intensity is measured from minus A to plus A on the y-axis, no units are given. The time is measured from 0 to 6.0 miliseconds on the x-axis. Intensity is represented as a damped 0 1.0 2.0 30 40 50 6.(oscillation. It starts from A at zero time and equals approximately one twentieth of A at 6 milliseconds. Intensity has 31 maxima and 30 minima from 0 to 6.0 milliseconds

Answer 1

Part A: The period of 30 oscillations is 6x10-s. The period of oscillation is, T = Calculate the frequency of oscillations as follows: 6x10-5 -0.2x10-s 30 0.2x10-s = 5.0x10 Hz = 5.0 kHz Part B: At t=3ms, the amplitude is A== Calculate the time constant as follows: A= Age i i = In (5)** --In5 3 ms In 5 =1.864 ms 1.9 ms