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The development of acoustic experiments for off-campus teaching and learning

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2011 Phys. Educ. 46 281

(http://iopscience.iop.org/0031-9120/46/3/004)

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The development of acousticexperiments for off-campusteaching and learningGraham Wild and Geoff Swan

School of Engineering, Edith Cowan University, 270 Joondalup Drive, Joondalup, WA 6027,Australia

E-mail: G.Wild@ecu.edu.au and G.Swan@ecu.edu.au

AbstractIn this article, we show the implementation of a computer-based digitalstorage oscilloscope (DSO) and function generator (FG) using the computer’ssoundcard for off-campus acoustic experiments. The microphone input isused for the DSO, and a speaker jack is used as the FG. In an effort to reducethe cost of implementing the experiment, we examine software available forfree, online. A small number of applications were compared in terms of theirinterface and functionality, for both the DSO and the FG. The software wasthen used to investigate standing waves in pipes using the computer-basedDSO. Standing wave theory taught in high school and in first year physics isbased on a one-dimensional model. With the use of the DSO’s fast Fouriertransform function, the experimental uncertainly alone was not sufficient toaccount for the difference observed between the measure and the calculatedfrequencies. Hence the original experiment was expanded upon to include theend correction effect. The DSO was also used for other simple acousticsexperiments, in areas such as the physics of music.

Introduction

University graduates are increasingly expected tobe work-ready and be able to have and applydiscipline knowledge in a practical way. Inscience and engineering courses, laboratory workhas traditionally been an important component ofan undergraduate degree. This can be expensivedue to specialized equipment and the significantsupervised contact time in the laboratory to masterexperimental skills.

With Australian universities under pressureto reduce costs, contact time between studentsand staff has been reduced. In particular,laboratory programmes, which have small student-

to-staff ratios and expensive equipment, havebeen specifically targeted as a quick way ofreducing costs. In a recent survey [1], Australianuniversity physics departments reported the abilityto upgrade/upkeep laboratories and laboratorystaff was a major challenge. The decrease instudent laboratory time over the last two decadeshas been most evident in large first year classeswhere university managers have been able toquickly reduce costs.

We have been investigating whether someexperiments might be undertaken using materialsat home with a small amount of university suppliedsupplementary equipment. Previous work hasshown that there are some excellent experiments

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from physics for off-campus students [2], andthis method is utilized extensively by the OpenUniversity in the UK. Introducing some off-campus experimental work could both maintainthe practical portion of the course for on-campusstudents as well as providing a way for off-campus students to do laboratory work at home.Other work has looked at the implementationof remote laboratories [3]. Here, webcams areutilized so students can visually interact withlaboratory equipment they are operating remotelyvia a computer interface [4].

We believe that some experiments that usebulky and expensive specialist equipment in thelaboratory setting could be done by students athome. Specifically in undergraduate acousticscourses, experiments typically involve the use ofdigital storage oscilloscopes (DSOs) and functiongenerators (FGs). These relatively expensive andbulky pieces of bench-top equipment make itprohibitive for external, distance, or off-campusstudents to be involved, without attending aresidential school. However, there is a growingdemand, particularly from the engineering sector,for courses to be more available remotely. Tothat end, ECU is investigating the possibility ofremote laboratory programmes in its courses. Inthis article, we show how students can undertakeexperimental work in acoustics at home using aPC and some inexpensive and easily providedequipment.

Freely downloadable software can turn a PCinto a digital storage oscilloscope (DSO) and func-tion generator (FG) to investigate sound waves.We demonstrate how students might conductexperiments at home using the microphone andspeaker jacks of the PC soundcard for input andoutput respectively. Fundamental experiments onstanding waves and resonance in pipes as wellas the physics of sound and music are describedhere. Resonance frequencies are calculated andmeasured for standing waves in pipes and thefast Fourier transform (FFT) function is usedto show frequencies present in musical notes.Standing waves can be conceptually difficult forstudents and experimental work has been shownto be important in helping students understand thistopic [5].

This is a low-cost system that has theversatility for use with a wide range of signals.Experiments can be conducted by students

both on and off-campus and the equipmentis sensitive enough to see the end effect forresonant frequencies in pipes. This systemmight also be adapted by secondary schoolswhere sound is studied in the physics curriculum.Other work using the same software has alsoshown that it can be successfully utilized forAC electricity experiments [6]. This wouldthen enable additional experiments that utilizeelectrical signals to be performed. Examplesof these include measuring the acceleration dueto gravity [7] and measuring the coefficient ofrestitution [8].

SoftwareDigital storage oscilloscope

There are a small number of freely download-able soundcard-based oscilloscopes. These in-clude Zelscope [9], BIP Electronics Lab Oscillo-scope [10], Virtins Sound Card Oscilloscope [11],Xoscope (for Linux) [12], and Soundcard Oscil-loscope [13]. The licence for the use of thesevaries from program to program. Some arefreeware [10, 12], others have free trials [9, 11]then require a licence, and others have optionallicences [13]. For an extended program, eithera free use or licensed program will be required,however, the cost associated with licensing theseis low, such that an individual student, or theinstitution would be able to cover (Zelscope forexample has a site licence of $99.95 and one coulddiscuss the use of a site licence to cover all externalstudents).

Function generator

In addition to the oscilloscopes, there is also anumber of freely downloadable soundcard-basedfunction generators including Virtins Sound CardSignal Generator [11], Test Tone Generator [14],and Tone Generator [15]. In addition to these,Soundcard Oscilloscope [13] has its own built-in signal generator. As with the oscilloscopesoftware, various licence options exist with thesignal generator applications.

Software choice

Several of these oscilloscope applications weretested for the purpose of comparison [16]. Thisinvolved looking at the ability of the applicationto measure the frequency of standing waves in

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Figure 1. Screenshot of Soundcard Oscilloscope (left), and in the signal generator mode (right).

pipes. The applications were not tested foraccuracy, but for usability. This work assessed,comparatively, how easy it was to perform a pre-existing laboratory session, using the computer-based oscilloscope in place of the bench top DSO.The conclusion of this work was that SoundcardOscilloscope [13] with its real-looking interface,spectrum analyser functionality and built-in signalgenerator, was the best choice. The wonderfulbyproduct of this is that Soundcard Oscilloscope isfree for public education purposes. Figure 1 showsscreenshots of Soundcard Oscilloscope, for boththe oscilloscope (left) and the signal generator(right).

TheoryA standard experiment to be conducted in firstyear laboratories is the investigation of standingwaves in pipes. This type of experiment is idealfor familiarizing students with the oscilloscope(either analogue or a DSO). Open–closed pipesare typically used, since it is easier to generatea resonant frequency in them. Students, bothhigher and lower undergraduates, are taught thatthe wavelength of the standing wave in the pipe isrelated to the length, in the same way as standingwaves on strings/springs. This means that thefundamental frequency, f , can then be expressedas [17]

f = c

4L, (1)

where c is the speed of sound, and L is thelength of the pipe. This assumes that the pipe isone-dimensional like the string/spring, where thesound waves in the pipe are planar. However, this

Figure 2. Open–closed pipe showing the hemispherical wave front and the 0.3d relative to the radius.

0.5d

0.3d

one-dimensional model fails to work at the openend of the pipe. The sound exiting from the end ofthe pipe is not planar, it is in fact hemispherical,since the sound radiates away from the end ofthe pipe isotropically. The average height of thehemisphere then needs to be added to the length ofthe pipe to give the effective length; this then givesthe fundamental frequency as [18]

f = c

4(L + 0.3d), (2)

where d is the diameter of the pipe. The endcorrection effect is depicted in figure 2.

The problem with including the end correc-tion effect is that the resonant frequency is afunction of two variables, that is, f (L, d). Toovercome this problem, the solution in theory,and as we show the implementation, is simple;however, the theory may be considered to becomplicated. The solution is to use multiple linearregression. Based on the idea that MicrosoftOffice™ is likely to be located on the desktopPC that is being used as the DSO and FG,Excel™ can be utilized to perform the multiplelinear regression. This, as mentioned above, issimple in practice. First the data need to be

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G Wild and G Swan

Figure 3. Screen shot of the frequency analysis function.

linearized, which is done by regressing R andd versus c/4 f . The result of this is regressioncoefficients of 1 for L, and 0.3 for d .

Experimental methodologyPhysics of music

Utilizing just the DSO, experiments were per-formed to look at the sound from musical in-struments. This is an ideal experiment to utilizethe oscilloscope, in particular the FFT spectrumanalyser functionality. Musical instruments cancommonly be found in the home, so equipmentis available. If not, a simple and cost-effectiveinstrument to use is a recorder. These are typicallyavailable from a variety of stores for a couple ofdollars.

The experiment conducted utilized varioustuning forks, and a recorder. The tuningforks represent ideal reference frequencies tocharacterize the performance of the DSO interms of uncertainty. This gives students anopportunity to investigate the concepts of precision

and accuracy. Clearly the method here is not veryinvolved, the tuning fork is simply struck againstthe knee causing it to vibrate, and then it is broughtclose to the microphone. The software can beset to the FFT mode (shown in figure 3), and thebox marked ‘peak hold’ can be checked. Afterthe spectrum has been captured, the oscilloscopecan be stopped, and the data and figure can besaved. The onscreen display also shows the peakfrequency.

After looking at the single frequency spec-trum of the tuning fork, musical instruments willoffer a more interesting analysis. The samemethod used for the tuning fork can be usedfor a musically instrument. Different notes canbe played and the difference between them canbe analysed quantitatively. Although the actualexperimental method for this part of the workis minimalistic, it is important to remember thatFourier’s theorem and the FFT will usually be seenfor the first time when conducting experimentsat this level. Hence, there is a substantialtheory to walk the students through, and how the

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time-based signal corresponds to the frequencyspectrum. Having said that, a similar simpleexperimental method could be used to capturetime-based signals, and then a software packagecould be used to do the FFT.

Standing waves

The work on standing waves in pipes wasconducted in three stages. The first of these was acomparison between the previous laboratory basedexperiment, utilizing an analogue oscilloscope,the new DSO for use in the teaching laboratory,and the computer-based soundcard oscilloscopeto be used by off-campus students. The secondstage involved a comparison between the previouslaboratory based experiment, which involvedblowing across the top of the pipe, and analternative method utilizing a signal generator anda speaker to induce resonance in the pipe. Thethird and final stage involved looking at a largesample size of pipes to determine if the endeffect correction can be accurately determined bystudents.

In the first stage, we performed the typicalexperiment conducted in our first year laboratoriesfor investigating standing waves in pipes. Theprimary goal of this experiment is to familiarizestudents with the oscilloscope. Here open–closedpipes are used, since it is easier to generatea resonant frequency in them. The resonantfrequency of the pipe is generated by blowingacross the open end. The period is measured usingthe oscilloscope with an attached microphone. Forthis work, we compared the analogue oscilloscopeused in the teaching laboratory, with the newDSO, and the PC soundcard-based oscilloscope.The experiment was performed with all threeoscilloscopes, to ensure that the off-campusstudents could effectively repeat the experiment.To calculate the theoretical values, the length anddiameter of the pipes were measured using a pairof vernier callipers. To assess the effect of themeasuring device, a rule was also used to measurethese dimensions for comparison.

The second stage of the experiment was acomparison between the two methods of inducingthe resonant frequency in the pipe. We selecteda small number of the 19 readily available open–closed pipes. Then we generated the resonantfrequency of the pipe by blowing across theopen end. The PC oscilloscope was used to

Figure 4. Experimental setup for the frequency sweep of the pipe.

determine the frequency from both the time-basedsignal and the frequency spectrum. Next, theresonant frequency of the pipe was generatedusing a sympathetic vibration method. The signalgenerator was used to transmit a tone from thePC’s speaker. The FG has a building sweepfunction, where the start frequency and the stopfrequency can be set, along with the time requiredto complete the sweep. The open end of thepipe was positioned between the speaker and themicrophone, with the pipe perpendicular to thesound propagation. This will then generate asympathetic vibration in the pipe, which will bemaximal at the resonant frequency of the pipe. Thefrequency spectrum was captured using the ‘peakhold’ function in the FFT mode. The experimentalsetup is depicted in figure 4.

In the final stage, the resonant frequency ofall 19 pipes was measured, comparing the valuesto the theoretical values from the 1D model andthe end correction effect. This data was then usedfor the multiple linear regression. Here, the FFTfunction on the PC soundcard oscilloscope wasused with the ‘peak hold’ mode, while the resonantfrequency of the pipe was generated by blowingacross the open end.

ResultsPhysics of music

Three tuning forks were used to investigate thefrequency spectrum analyser. These were an A flatat 426 Hz, an A at 435 Hz, and a C at 512 Hz.The frequency spectra for the A note tuning forkand the C note tuning fork are shown in figure 5.In the spectrum we can see the strong signal at thefrequency of the tuning fork, 435 Hz, and a smallsignal at the first harmonic, 870 Hz.

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Figure 5. Frequency spectrum of the signal from the 435 Hz, A note tuning fork (left), and the 512 Hz, C note tuning fork (right).

frequency (Hz)

1.81.61.41.2

0.80.60.40.2

00 100 200 300 400 500 600 700 800 900 1000 900 1000

1

frequency (Hz)

0.90.80.70.60.50.40.30.20.1

00 100 200 300 400 500 600 700 800

Figure 6. Frequency spectrum of an A note (left) and then a C note (right) played on the recorder.

frequency (Hz)

1.61.41.2

0.80.60.40.2

00 1000 2000 3000 4000 5000

1

frequency (Hz)

1.61.41.2

0.80.60.40.2

00 1000 2000 3000 4000 5000

1

Next, the spectrum analyser was used tolook at the output from a recorder at variousnotes. Figure 6 shows the frequency spectrumof both an A note and a C note played on therecorder. We can see the interesting features ofthe recorder’s spectrum, which is lost in the timedomain information. Specifically students caneasily see the harmonics, evenly spaced, and thefundamental frequency, which both occur at twicethe frequency of the tuning forks, 870 Hz for theA, and 1024 Hz for the C.

Standing waves

The results for the first stage of the standingwave experiments were mixed, some results wereobvious, and other results were surprising. Theobvious result is that it is difficult to determinethe period of the waveform on an analogueoscilloscope. This problem is easily overcome ona DSO and PC-based oscilloscope with the abilityto single trigger and store the waveform. Also, ananalogue oscilloscope has a poor resolution, givingit a considerably large uncertainty compared to adigital oscilloscope. The inability of an analogue

oscilloscope to precisely measure the period of awaveform, and hence the frequency, means that thesimple 1D model of the standing wave in pipes isadequate with the large experimental uncertainty,assuming the diameter of the pipe is suitablynarrow. Theoretically, the maximum diameterof a pipe to ignore the end correction is whenthe difference in the resonant frequency predictedby (1) is within the experimental uncertaintycombined with the resonant frequency predictedby (2). The surprising result, for the pipesconsidered here, was that the use of the PC-basedoscilloscope will not only enable off-campusstudents to effectively repeat the experimentconducted by on-campus students, it also meansthat the PC-based oscilloscope (and DSOs) willprovide students with the opportunity to conductmore accurate experiments.

The results of the second stage, the compar-ison between the various methods to experimen-tally measure the resonant frequency, are shown intable 1. The results for only two pipes are shown,which were randomly selected, one from thecluster of shorter pipes, and one from the cluster

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Figure 7. Frequency sweep from 300 Hz to 700 Hz on pipe number 4, normalized.

6

5

4

3

2

1

0300 400 500 600 700

frequency (Hz)

rela

tive

ampl

itude

(ar

bitr

ary

units

)

Figure 8. Frequency sweep from 300 Hz to 700 Hz on pipe number 4, and the frequency response of the speaker–microphone system without the pipe.

0.025

0.020

0.015

0.010

0.005

0300 400 500 600 700

frequency (Hz)

rece

ived

sig

nal (

V)

with pipewithout pipe

of longer pipes. These results again show thatthe 1D model does not agree with the measuredfrequency, within the experimental uncertainty.We do see, however, that the end correction effectvalue agrees with the measured results within theexperimental uncertainty. The most significantresult from this is that blowing across the openend of the pipe generates a resonant frequencythat is close to the frequency measured from thefrequency sweep. This is true, provided the signalin the pipe is generated in a manner that minimizesany interference with the sound exiting the pipe.That is, air needs to be blown across the end of thepipe to generate the resonance, and not down thepipe.

Figure 7 shows the frequency sweep of oneof the pipes (number 4). To remove the frequencyresponse of the microphone and the speaker, thereceived signal with the pipe between the speakerand the microphone, was divided by the received

Figure 9. Comparison between the experimentally measured resonant frequency, and those predicted theoretically, from both the 1D model and the end correction effect.

1100

1000

900

800

700

600

5001 3 5 7 9 11 13 15 17 19

pipe number

freq

uenc

y (H

z)

experimental1D modelend correction effect

Table 1. Comparison of experimental methods todetermine the resonant frequencies of 2 pipes.

Parameter Pipe 16 Pipe 4 Units

L (vernier) 0.083 52 0.148 06 mL (rule) 0.084 0.148 md (vernier) 0.019 68 0.019 76 md (rule) 0.02 0.02 mf (1D) 1018 580 Hzf (end effect) 950 553 Hzf (scope) 915 534 Hzf (FFT) 928 540 Hzf (sweep) 940 545 Hz

signal without the pipe. The individual signals areshown in figure 8.

The results of the comparison between theresonant frequency measured experimentally andthose predicted theoretically by (1) and (2) isshown in figure 9. The results clearly showthat the 1D model does not suitably explain theobserved resonant frequency, with the predicatedvalue consistently above the measured value.However, by including the end correction effect,the data agree to a very high degree, well withinthe experiment uncertainty previously discussed.From figure 9, we can see that the resonantfrequency predicted by the 1D model becomeseven more significant when the fundamentalfrequency is higher. This is explained by thefact that the end correction effect becomes moresignificant as the length of the pipe gets shorter.

The regression analysis from the 19 samplepipes, where the resonant frequency was generatedby blowing across the open end, is shown in

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Table 2. Regression analysis output.

Coefficient Standard error

Intercept −0.0011 0.0015X variable 1 (d) 0.317 0.0594X variable 2 (L) 1.0041 0.0078

table 2. We see the coefficient for the interceptis −0.001 ± 0.002, which effectively means itis zero. The coefficient of the length variableis 1.004 ± 0.008, which includes one withinthe statistical uncertainty. Finally, the diametercoefficient is 0.32 ± 0.06, which includes 0.3 withthe statistical uncertainty. Even when just blowingacross the open end of the pipe to generate theresonant frequency, the experimental results agreewith the end correction effect theory within thestatistical uncertainty. For comparison, a simplelinear regression analysis was performed for Lversus c/4 f . The result of this was a coefficientfor L of 1.02 ± 0.01. This value does not agreewith the simple 1D model’s predicted value of 1within the statistical uncertainty.

DiscussionThe potential benefits of being able to performsome practical work at home are several. Forstudents, the ability to be able to do theseexperiments at their own pace and without thetime limits of a timetable slot should assistunderstanding. At ECU it is common forstudents to have significant commitments outsidetheir university studies, so the flexibility ofdoing experiments in their own time is also anadvantage. In this study, undertaking practicalwork in acoustics at home would free up valuablelaboratory time for other experiments which couldimprove the educational value of the course to thestudents. On the downside, students do not haveaccess to a demonstrator at home to help with anydifficulties and any occupational health and safetyissues that arise may be more difficult to address.

Findings

Overall, the software was simple and effective touse. Looking at the signals from the tuning forksgives students an ideal way to visualize the signalin the time domain on the oscilloscope, and tosee the frequency domain equivalent, of a devicethat emits only a single frequency. Although a

tuning fork is not necessarily something that iscommon in the home, the intention would be toinclude a tuning fork in the small experimentalkit that would be sent to the student. The samecould also be done with the recorder, givingstudents instructions on generating the requirednotes. Students would also be able to investigatethe spectrum of any other instruments that theyhave available to them.

The frequency sweep method was so ef-fective, that it shows the variation of acousticimpedance, not just the resonant frequency. Thismeans that the experiment could be adapted tomore specific acoustic experiments at high levelsin a university. The real value of a paper isreflected in the nature, soundness and clarity ofthe conclusions, so particular care should be takenwith this section.

Future work

The use of the FG has not been overly stressedin the work considered here. The use of theFFT function and blowing across the pipe isenough to generate data to give the end correction.However, using the FG as an audio generatorwould allow the psycho-physics of sound to beinvestigated; specifically, the lower frequencyresponse of hearing. It would also be possible tolook at perceived tones [19].

Although Soundcard Oscilloscope has provento be very effective, with all the required function-alities necessary to undertake this work, other soft-ware is required. Ideally, we would like to look atthe ability to use Labview [20] (which was used todevelop the Soundcard Oscilloscope software) todevelop in-house software. This would mean thatthe software is always available and maintained,keeping it up to date and, more importantly, freeto use, if the licence for Soundcard Oscilloscopewere to change. This would make an ideal projectfor a physics/computer science student.

ConclusionWe have demonstrated the use of a PC soundcard-based oscilloscope for acoustic experiments thatcan be conducted by students at home. Theexperiments shown here were equivalent to thoseconducted within a teaching laboratory setting,and in the case of analogue oscilloscopes usedin the laboratory just three years ago, they

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were significantly better. We showed howthe soundcard-based oscilloscope and functiongenerator could be used to determine the resonantfrequencies of standing waves in pipes withsufficient precision and accuracy to see theend effect. We also showed how the FFT-based spectrum analyser enables students toaccurately visualize the frequency spectrum frommusical instruments. The PC soundcard-basedoscilloscope provides a cost-effective option fordelivering experimental work in acoustics into thehome, and also providing both the student and theuniversity with more flexibility.

Received 14 October 2010, in final form 10 January 2011doi:10.1088/0031-9120/46/3/004

References[1] Sharma M, Mills D, Mendez A and Pollard J 2005

Learning Outcomes and CurriculumDevelopment in Physics (Surry Hills, NSW:Australian Universities Teaching Committee)

[2] Mendez A et al 2005 Snapshots: Good Learningand Teaching in Physics in AustralianUniversities (Melbourne, VIC: CarrickInstitute)

[3] Cooper M and Ferreira J M M 2009 Remotelaboratories extending access to science andengineering curricular IEEE Trans. Learn.Technol. 2 342–53

[4] Scanlon E, Colwell C, Cooper M andDi Paolo T 2004 Remote experiments,re-versioning and re-thinking science learningComput. Educ. 43 153–63

[5] Bhathal R, Sharma M D and Mendez A 2010Educational analysis of a first year engineeringphysics experiment on standing waves: basedon the ACELL approach Eur. J. Phys. 31 23–35

[6] Wild G, Swan G I and Hinckley S 2010 ACelectricity experiments for off-campus teachingand learning Proc. 19th Australian Institute ofPhysics Congr. paper 261

[7] Ganci S 2008 Measurement of g by means of the‘improper’ use of sound card software: amultipurpose experiment Phys. Educ.43 297–300

[8] Wadhwa A 2009 Measuring the coefficient ofrestitution using a digital oscilloscope Phys.Educ. 44 517–21

[9] Zelscope, viewed August 2009 www.zelscope.com

[10] BIP Electronics Lab Oscilloscope-3.0, viewedAugust 2009 www.electronics-lab.com/downloads/pc/002/index.html

[11] Virtins Technology, viewed August 2009www.virtins.com

[12] xoscope for Linux, viewed August 2009http://xoscope.sourceforge.net/

[13] Soundcard Oscilloscope, viewed August 2009www.zeitnitz.de/Christian/scope en

[14] Esser Audio—Timo Esser’s Audio Software,viewed August 2009 www.esseraudio.com

[15] Tone Generator, viewed August 2009 www.nch.com.au/tonegen/index.html

[16] Oswald D 2009 Development of a soundcardbased oscilloscope experiment for off-campusstudents Physics Project Report (Perth, WA:Edith Cowan University)

[17] Serway R A and Jewett J W 2008 Physics ForScientists and Engineers with Modern Physics(Belmont, CA: Brooks/Cole-ThomsonLearning)

[18] Johnston I 2002 Measured Tones: The Interplayof Physics and Music (New York: Taylor andFrancis) pp 189–91

[19] Roederer J G 1975 Introduction to the Physicsand Psychophysics of Music (New York:Springer)

[20] National Instruments: Labview, viewed October2010 www.ni.com/labview/

Graham Wild is new to physicseducation, having been awarded his PhDin physics in 2010. At ECU he iscurrently the aviations systems lecturerand his primary research interest is inaircraft structural health monitoring. Heis also interested in education research,specifically for physics and engineering,and their application to aviationeducation, to provide research-informedteaching.

Geoff Swan has been involved in physicseducation as a secondary school teacherand university lecturer for over 20 years.At ECU his primary role is to look afterthe first year physics programme and hisprimary research interest is in physicseducation. In 2008 he was awarded acitation for sustained teaching excellenceand leadership in physics education fromthe Australian Learning and TeachingCouncil.

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