Physics lab. These are pretty simple questions but I suck with physics. Please h
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Question
Physics lab. These are pretty simple questions but I suck with physics. Please help! 6. WAVES AND SOUND 6.2.3 Complex Waveforms In this part of the laboratory we aim to answer the question, 'how do simple waveforms combine to create more complex ones. One example is the ragged or wavy sound you hear when two pure tones very close in frequency are combined. Musicians use this phenomenon, called beats, to help them tune their instrument to a standard pitch. Open the file BeatExperiment. This contains two graph windows and a table window. Place your two tuning forks as close together as possible with the microphone held midway between the openings of their attached boxes. Record from one tuning fork at a time, hitting each equally and saving the two runs in the same file. If one waveform is much larger than the other, adjust the position of the microphone or the heaviness of strike to make them similar. To delete any runs that you do not want, go to the Data menu. Display the two runs superimposed on the upper graph. Before printing, go to Page Setup from the File menu and select the landscape mode and letter-size paper. Then choose Print Window from the File menu to print just the window that is selected. 1. Determine the frequency of the second tuning fork and record it. 2. On the printout of the two waveforms, indicate where you would expect the maximu amplitude of your combined waveform to be. 3. What frequency(s) do you expect to hear when both tuning forks are sounded?Explanation / Answer
1) To determine the frequency, check the number of cycles that are repeated in one time period. The frequency is also given by 1/time period
2) When you see the waveforms, keep them one above the other. Make sure that the time scale is the same. That is zero of the time scale of the first tuning fork matches the zero of the time scale of the second tuning fork. Also, make sure that the subsequent seconds match. Basically, the calibration of the time axes should be the same. Once that is done, the waveforms will have peaks and troughs. This is for both the waveforms. Points where the two peaks match, the resultant will be one high peak( maximum amplitude), the time where the two troughs match that will the time points of minimum amplitude. It is these max and min combined amplitudes that are responsible for the phenomenon of beats.
3) When both the forks are sounded together, we expect to hear the sound which has frequency which is a difference of the resonant frequency of the two tuning forks.
Say if one tuning fork has frequency f and the other has f +n, the frequency that will be heard when both are struck together is f+n - f = n. This is the frequency of the beats ( n beats/second)