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E3 Teacher Summer Research ProgramLynn Harvey, Charlotte High SchoolIntegrated Physics and Chemistry, grade 9Unit !aves and Energy Trans"er

Lesson To#ic !ave Ty#es and CharacteristicsLesson To#ic !ave Ty#es and CharacteristicsAdapted from Seismic Waves and the Slinky: A Guide for Teachers

The IRIS ConsortiumPro"$ La%rence !$ &raile, 'e#artment o" Earth and (tmos#heric SciencePro"$ La%rence !$ &raile, 'e#artment o" Earth and (tmos#heric SciencePurdue University

Unit Goals:

Students %ill use #hysical models o" o)*ects and events as tools to o)serve andunderstand %aves and their #ro#erties$

Students %ill use mathematical models o" events to descri)e and #redict %averelationshi#s$

Students %ill a##ly +no%ledge o" %ave ty#es o" inter#ret seismogra#hs$

The student %ill measure o)served %avelengths, am#litudes and "reuencies$ The student %ill e-#erimentally determine the relationshi# )et%een %avelength,

"reuency, and velocity$

Lesson Objectives:

The student %ill o)serve models o" transverse and longitudinal %aves and identi"yThe student %ill o)serve models o" transverse and longitudinal %aves and identi"y#arts o" each %ave ty#e$#arts o" each %ave ty#e$

The student %ill identi"y %ave ty#es )ased on the direction o" #article motion inThe student %ill identi"y %ave ty#es )ased on the direction o" #article motion in

relation to the direction o" #ro#agation$relation to the direction o" #ro#agation$

The student %ill o)serve %ave )ehavior through media and across )oundaries andThe student %ill o)serve %ave )ehavior through media and across )oundaries andma+e #redictions a)out e-#ected )ehavior$ma+e #redictions a)out e-#ected )ehavior$

orrelation to !" T#$S:

Integrated Physics and Chemistry, grade 9The student is e-#ected to

%A. 'emonstrate %ave ty#es and their characteristics through a variety o" activitiessuch as modeling %ith ro#es and coils, activating tuning "or+s, and inter#reting data onseismic %aves/

%&''emonstrate %ave interactions including inter"erence, #olari0ation, re1ection,re"raction, and resonance %ithin various materials/

(ote Italici0ed titles are activities "rom the teaching guide 2Seismic !aves and theSlin+y ( uide "or Teachers4 )y Pro"$ La%rence !$ &raile 5The IRIS Consortium, PurdueUniversity. availa)le on the !e)at %%%$eas$#urdue$edu67)raile6edumod6slin+y6slin+y$htm

http://www.eas.purdue.edu/~braile/edumod/slinky/slinky.htmhttp://www.eas.purdue.edu/~braile/edumod/slinky/slinky.htm

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!nstructional Se)uence *based on the %# !nstructional +odel'

#n,a,ement8$ Illustration of Energy Carried by the Waves5Slin+y connected to %ood )loc+

%ith a2house4 attached to the )loc+.

$ Slinky Demonstrations of P and S Waves

#-ploration 5heterogeneous grou#s e-#lore %ave #ro#agation, )ehavior andcharacteristics.

E-#loration 8Slinky Demonstrations of P and S WavesE-#loration Waves in Water Experiment

E-#loration 3: Ree!tion of Waves E-#loration : Ree!tion of Waves E-#loration ; "ttenuation of Waves

#-planation 5!hole

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distur)ance #ro#agates along the slin+y$ ("ter the energy #asses, the coilso" the slin+y return to their original, undistur)ed #osition$ The direction o"#article motion is in the direction o" #ro#agation$

(for transparency)

The #erson %ho creates the shear distur)ance does so )y moving his or herhand uic+ly u# and then do%n$ This motion generates a motion o" the coilsthat is #er#endicular to the direction o" #ro#agation, %hich is along theslin+y$ Gote that the #article motion is not only #er#endicular to the

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direction o" motion )ut also in the vertical #lane$ Dne can also #roduceShear %aves %ith the slin+y in %hich the motion is in the hori0ontal #lane )ythe #erson creating the source moving his or her hand uic+ly le"t and thenright$ The #ro#agation o" the S %ave )y the slin+y is illustrated in igure 8:$Gotice that, although the motion o" the distur)ance %as #urely#er#endicular to the direction o" #ro#agation 5no motion in the distur)ingsource %as directed along the slin+y., the distur)ance still #ro#agates a%ay"rom the source, along the slin+y$

/igure #.$ Diagram sho0ing ho0 1ve slinkys !an be atta!hed to the edge of a 0oodblo!k$

Photogra#hs o" the =ve slin+y model are sho%n in igures 8 and 89$ !hen the slin+ysare stretched out to dierent #ositions 5=ve #eo#le hold the end o" one slin+y each. anda P or S %ave is generated at the %ood )loc+, the %aves #ro#agate out in all directions$

The =ve slin+y model can also )e used to sho% that the travel times to dierent locations5such as seismogra#h stations. %ill )e dierent$ To demonstrate this eect, %ra# a smal#iece o" ta#e around a coil near the middle o" the slin+y "or one o" the slin+ys$ Have the#erson holding that slin+y com#ress all o" the coils "rom the outer end to the coil %ith the

ta#e so that only one hal" o" the slin+y is e-tended$ (lso, attach an additional slin+y,using #lastic electrical ta#e, to the end o" one o" the slin+ys$ Have the #erson holdingthis dou)le slin+y stand "arther a%ay "rom the %ood )loc+ so that the dou)le slin+y is

"ully e-tended$ !hen a P or S %ave is generated at the %ood )loc+, the %aves thattravel along the slin+y %ill arrive at the end o" the hal" slin+y =rst, then at a##ro-imately

the same time at the three regular and=nally, last at the dou)le length slin+y$ The dierence in travel time %ill )e verynoticea)le$

Wood block

Slinky

Holes,6.3 cm apart

Screw and washer

~ 10 cm

~ 25 cm

Five Slinky P and S Wave Propagation Demonstration

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Sources

Biscontin, G. Seismic !ri""erin" Su#marine Slopes$, personal narrati%e,course notes

Boston &useum o' Science

Braile, (awrence )., Seismic Waves and the Slinky: A Guide ForTeachers, !he *ris +onsortium, urdue -ni%ersit, www.iris.edu

+am#rid"e hsics /utlet, Physics and Chemistry Investigations,

!om Hsu, h. 0.

lton, 0a%id 2., Soils Magic,3S+, Geotechnical Special u#. 114

5&3, &ultiha7ard Buildin" 0esi"n Summer *nstitute 8&B0S*9

J ?ramer, Steven L$, 2eote!hni!al Earth)uake Engineering, Prentice Hall,899F, F;3 ##$

J Pa#ert, S$, 3indstorms: Children4 Computers4 and Po0erful IdeasJ Russell,'an, !ave motion animation, ?ettering University (##lied Physics

!e:as ducation 3"enc, Science !;S

!row#rid"e and B#ee, Teaching Secondary School Science, &errill, 1