Comp puter Mod dels Design n for Teac ching and L Learning u

Transcription

Oral Preseentation [PS.02.099.a] The World C
Conference on Phyysics Education 1-6 July 2012
Compputer Moddels Designn for Teacching and L
Learning uusing Easyy Java Sim
mulation
Looo Kang Law
wrence WEE1, Ai Phing L
LIM2, Khoonn Song Aloysius GOH5 , S
Sze Yee LYE
E1, Tat Leongg
LEE
E2, Weimingg XU2, Giam Hwee Jimmyy Goh3, Cheee Wah ONG4, Soo Kok NG
N 4, Ee-Peow
w LIM5, Chew
w
6
6
1
7
L
Ling LIM , W
Wee Leng Jooshua YEO , Matthew ON
NG ,Kennethh Y T LIM
1
Ministry of Education, Eduucation Technoloogy Division (ETD
D), Singapore
2
Ministrry of Education, R
River Valley Highh School (RVHS)), Singapore
3
Minnistry of Educationn, Yishun Junior C
College (YJC), Siingapore
4
Minnistry of Educatioon, Innova Junior College (IJC), Sinngapore
5
Minisstry of Education,, Anderson Juniorr College (AJC), S
Singapore
6
Ministtry of Education, S
Serangoon Juniorr College (SRJC),, Singapore
7
National Innstitute of Educattion, Nanyang Teechnological Univversity, Singaporee
[email protected], [email protected], [email protected], [email protected], [email protected],
lee_tat_leong@
@moe.edu.sg, xu_w
[email protected], [email protected], [email protected], [email protected], , lim_eepeow@
@moe.edu.sg, [email protected], [email protected], kenneth.lim@
@nie.edu.sg
A
Abstract: We are teachers w
who have beneefited from thee Open Sourcee Physics (Broown, 2012; Chhristian, 2010; Esquembre,
22012) commuunity's work annd we would llike to share some of the computer modells and lesson ppackages that w
we have
ddesigned and implemented in five schools grade 11 to 12 classes.
IIn a ground-upp teacher-leaddership (MOE,, 2010) approaach, we came ttogether to leaarn, advancingg the professioonalism (MOE
E,
22009) of physsics educators and improve sstudents' learnning experiences through suiitable blend (JJaakkola, 20122) of real
eequipment andd computer m
models where aappropriate . W
We will share ccomputer moddels that we haave remixed frrom existing
llibrary of com
mputer models into suitable learning
l
envirronments for innquiry of physsics customizeed (Wee & Maak, 2009) for tthe
A
Advanced Levvel Physics syyllabus (SEAB
B, 2010, 2012).
W
We hope otheer teachers wouuld find these computer models useful annd remix them to suit their ow
wn context, deesign better
llearning activiities and sharee them to beneefit all humankkind, becominng citizens for the world.
T
This is an eduuLab (MOE, 20012b; Wee, 20010) project fuunded by the N
National Research Fund (NR
RF) Singaporee and Ministryy
oof Education (MOE)
(
Singappore.
Keyword: Bleended Learning, S
Simulations, Com
mputer Models, Oppen Source Physics, Teacher Education, teacher proofessional developpment, Easy Java
Sim
mulations active leearning, educationn, e-learning, appplet, design, GCE Advance Level pphysics
PACS
S: 01.50.H- 91
1.10.-v 96.20.JJz 04.80.-y 996.20.Jz
Table 1: Sum
mmary of schoolss leading in the research
r
and imp
plementation of tthe lessons with computer
c
modell
Lead
school
Customizeed computer
moodel
RVHS
Collision ccarts (ideal)
AJC
Collision caarts (realistic)
AJC
Falling maggnet through
soleenoid
IJC
Ripplle tank
Geostatioonary orbit
YJC
Field strengtth & potential
Earth--Moon
Kepler’s 3 law
rd
SRJC
Superposition waves
Originaal model
author andd sub-author
coddes*
Francisco Esquembre
Fu-Kwunn Hwang*
Andrew
w Duffy*
Francisco Esquembre
Fu-Kwunn Hwang*
Andrew
w Duffy*
Francisco Esquembre
Andrew
w Duffy
Juan Aguirregabiria*
Fu-Kwunn Hwang*
Francisco Esquembre
Fu-Kwunn Hwang*
Andrew
w Duffy
Fu-Kwunn Hwang*
Andrew
w Duffy
Fu-Kwunn Hwang*
Todd Tim
mberlake
Wolfgangg Christian
Fu-Kwunn Hwang*
Figure
Number of
teachers
Number off
students
Scaling upp in
other
schoolss
1
3
242
SRJC
IJC
2
3
67
On goingg
3
8
198
RVHS,
SRJC
4
5
77
YJC
RVHS
6
250
On goingg
7
145
On goingg
5
6
7
8
9
Parallel Session 02.09|Date & Tim
me: 02.07.2012 / 13:00 - 14:30|Halll: D403 (3rd Flooor)
1/26
I..
INTRODUC
CTION
We use a free authoringg toolkit calleed Easy Java Simulation (E
EJS) (Esquem
mbre, 2012) thaat allows ordiinary teacherss to
ccreate computter models as ttools for interaactive engagem
ment (Adegokee, 2012; Hake,, 1998) in physics educationn.
Building oon open sourcce codes sharred by the Oppen Source Phhysics (OSP) community, and with helpp from the O
OSP
ccommunity suuch as Fu-Kw
wun’s NTNUJA
AVA Virtual Physics Laborratory (Hwangg, 2010), we customized seeveral Easy Jaava
Simulation (E
EJS) computer models (Figurre 1 to 9) that we hope manyy teachers will find useful. T
They are all doownloadable aand
ffree to redistriibute and use uunder creativee commons atttribution licennses from Digiital Library in NTNUJAVA
A Virtual Physsics
L
Laboratory (H
Hwang, 2010) and
a our workinng Google sitee https://sites.ggoogle.com/sitte/lookang/.
In chronollogical order of
o implementaation of the lesssons, these arre the lessons with computeer models that we have usedd to
iinteractively engage
e
(Hake, 1998) our studdents, makingg physics comee ‘alive’ and leearn through m
meaningful plaay (Lee, 2012)..
Aligned too our goal of sscaling up (Deede, 2007) meaaningful use of
o information and communications technnology (ICT) innto
ccurriculum, asssessment and pedagogy (M
MOE, 2008) wee would brieflyy describe Figgure 1 to 9 on these computeer models. Theese
ccomputer moddels can be ussed and furtheer customized (Wee & Makk, 2009) as sciientific inquiryy tools, suitinng teachers’ ow
wn
““particular intterests and eduucational poinnts of view, annd combine thee use of a corrrect pedagogiccal approach w
with the sensee of
ggiving to it theeir own flavor”” (Esquembre, 2002).
Figure 1. Coollision carts (ideal) model (Wee, 2012b;
2
Wee & Essquembre, 2008) dderived from Franncisco’s original w
work (Esquembree, 2009) showing
mathematiccal representations to illicit predictiive thinking abouut the concepts.
2/26
Lye, 2012) derived from Francisco’s original work ((Esquembre, 20099) with 3 scientifiic
Figure 2. Colllision carts (realisstic) model (Wee, Esquembre, & L
grraphs showing reaalistic spring moddelled during colliisions
Figure 3. Fallinng magnet througgh solenoid modell (Wee, Esquembrre, & Lee, 2012) dderived from Franncisco’s original w
work (Esquembree, 2010b) showingg a
loong solenoid show
w and the resultannt induced voltagee as the short bar magnet falls throough.
3/26
H
2012) deriived from Andrew
w’s original work (Duffy, 2010) shhowing pen paper
Figure 4. Riipple tank model (Wee, Duffy, Aguuirregabiria, & Hwang,
representtation of crest andd scalar field display of the interferrence pattern due to 2 point sources S1 and S2.
Figure 5. Geeostationary orbitt model (Wee, 20112a; Wee & Esquuembre, 2010) derrived from Franciisco’s original woork (Esquembre, 22010a) showing a
geostationary oorbit (red) and a ppolar orbit (white))
4/26
Figure 6. Two mass modell (Wee, Duffy, & Hwang, 2012a) dderived from Anddrew’s original woork (Duffy, 2009)) showing a 2 masss system with
gravitational and potential linees in 1 dimension
Figure 7. Earth--Moon model (W
Wee, Duffy, & Hw
wang, 2012b) derivved from Andrew
w’s original work (Duffy,
(
2009) shoowing a 1 dimensional realistic moodel
of the mooon and earth systeem useful for explloring escape veloocity concept.
5/26
w
(Timberlakee, 2010) showing earth and mars annd
Figure 8. Kepller’s 3rd Law systeem model (Timbeerlake & Wee, 2011) derived from Todd’s original work
thheir orbital trails ffor data collectionn of periods of plaanets.
Figure 9. Supeerposition of waves model (Wee, C
Christian, & Hwanng, 2009) derivedd from Christian’ss original work (C
Christian, 2008) shhowing 2 functionns
annd their resultant (red)
6/26
II.
METHO
ODS
T
Table 2: Researcch methods used by school River Valley High School (RVHS) and Anderson Junioor College (AJC)
School
RVHS
AJC
Researrch Method
Lesson study
Expeerimental withh pre-post test analysis
Stuudents in experrimental groupp
2422
677
Students inn control groupp
0
62
Teachers
3
3
A
A. RVHS
1) Setup
The studennts are seated in groups of 3 to 4 and are equipped with the workshheet and a lapptop loaded with the compuuter
m
model (Wee, 2012b; Wee & Esquembree, 2008). The questions in the worksheeet were adapteed from the N
Newtonian Tassks
IInspired by Phhysics Education Research by Curtis J. H
Hieggelke, to ssuit the particuular interest oof the teachers, curriculum aand
tthe language oof local studennts.
2) Workshheet
The workssheet (VI Apppendix A) usess open ended scenarios of thhe 3 different collisions witth lesson desiggn influenced by
ppredict-observve-explain (Lieew & Treagusst, 1995) strateegy, to allow sstudents to disscuss and collaaboratively decide on the m
most
aappropriate annswers to consolidate and exxtend their undderstanding thaat can be simulated using thee computer moodel.
3) Limitattion of study
Using the lesson studyy approach, liimitations of the study innclude reliancee on teacherss’ subjective observation aand
ddifficulties in reviewing the large amount of video footaage of the lessoon.
B
B. AJC
1) Setup
Figure 10. Lessoon classroom seatiing arrangement in
i AJC. Each studdent uses a personnal laptop with thee Collision carts (realistic)
(
computter model aided w
with
inquiry worksheet
w
questioons modified from
m Physics by Inquiry (McDermott, Shaffer, & Rosennquist, 1995)
The studennts are seated in
i groups of fiive and are equuipped with thhe worksheet and
a a laptop looaded with the computer model
((Wee, Esquem
mbre, & Lye, 2012). The innquiry questioons in the worrksheet were adapted from the Physics bby Inquiry (PB
BI)
qquestions (MccDermott, et all., 1995), to suuit the content of local curricculum and langguage.
2) Workshheet
The workssheet (VII Apppendix B) conntext of 2 glideers aims to prromote concepptualization off Newton’s Firrst Law (unifoorm
m
motion in fricttionless surfacces) and Newtoon’s Third Law
w of Motion (varying contacct forces preseent during colllision only, equ
qual
aand opposite aand on differennt bodies).
7/26
The workssheet focuses oonly on the exxample of colliision of gliderrs and pre-postt test questions are designedd to lead studeents
tto conceptualiize the same N
Newton’s Thrree Laws in m
multiple repressentations (Wong, Sng, Ng, & Wee, 20111). Students are
aasked to interrpret the f-t annd p-t graph. They are alsoo required to draw vector ddiagrams of fforces acting oon the gliderss at
ddifferent instaants. The questtions in the woorksheet aim tto improve stuudent’s mentall construction of concepts annd the processs of
kknowledge construction is thhe focus of thee lesson, guideed by teacher ffacilitated disccussion.
3) Limitattion of study
Using the classical pree-test post-testt research appproach, limitaations of the study includee students nott completing the
ppre/post-test tto their abilitiees and inability to randomlly divide into equivalent grroups as classses are alreadyy pre-defined by
sschool practices.
III.
DATA AND FINDINGS
A
A. RVHS
Some otheer teachers wennt into the classsroom to studdy the lesson annd these are soome of their obbservations.
We includde excerpts off the lesson stuudy notes by the teachers too give some tthemes and innsights into thee conditions aand
pprocesses duriing the laborattory lessons.
1) Need foor well scaffollded inquiry acctivities
“Students have difficultyy because therre weren’t enoough info giveen, no masses,, no velocitiess. Not used to such open cases
((tutorials – all open and shuut cases). “
2) Compuuter model cann support inquiry activities
“Students are not easily convinced thaat two moving objects colliding together coome to a compplete stop.”
wrong student (TH)
(
was ablee to
“(TH, YS and B) When faced with 2 contrasting thheories, the moore vocal or coonfident but w
cconvince the oother student (Y
me to the rightt conclusion.”
YS) of his ansswer. After thee simulation, bboth appeared to quickly com
t previous w
wrong answer tto look at whyy it was wrongg. Once the annswer is revealed, students teend
“They did not return to the
tto just focus oon theories whiich fit the answ
wers; regardlesss of their ownn feel that theyy feel somethinng is wrong.”
B
B. AJC
proved, no change and deteriorateed in post test scoores respectivelyy.
T
Table 3: Experim
mental and contrrol group comparrison, where ↑ 0 ↓ represents imp
N
No. of students participated
N
No. of students used in <g>
No. of students w
who improved
Average Pre test score
Max = 11 marks
Average Postt test score
Max = 11 marks
Experiimental Groupp
62
45
44
Controll Group
677
455
41
6.003
2.31
6.74 2.10
7.660
2.26
7.69 1.83
↑
0
↓
↑
0
↓
55%
25%
20%
3
32%
35%
33%
%
Newton’s F
First law
60%
20%
20%
6
60%
300%
10%
%
Newton’s Third
T
law
% of students improved
71%
61%
Table 3 suuggests a higheer percentage (55%) of studdents in the exxperimental grroup improvedd in the Newtoon’s 1st Law thhan
ccontrol group 32% while a fairly equivaalent number oof students im
mproved in Neewton’s 3rd Laaw. Overall, thhe percentage of
sstudents that im
mproved is (71- 61) = 10% higher in the eexperimental ggroup compareed to the contrrol group. The increase in poostppre test scoress is higher (1.556 2.93 vs 0.995 1.78) but the post scorees are fairly eqquivalent (7.600 2.26 and 77.69 1.83). T
The
.
.
sstandardized m
mean differencce of the experrimental over the
t control grooup is
0.21 which is medium inn effect.
.
The averagge test scores in
i percentage (Figure 11) suuggest higher sscore in Newtoon’s 1st Law ass well.
8/26
80%
Average
Score
Average tes
st scores in Pe
ercentage
E
Experimental
C
Control
75%
70%
65%
60%
55%
50%
Pre N1L Post N1L
N
Pre N3L Post
P
N3L Pre-to
otal Post Total
Figure 11. Averaage test scores in percentage of thee 11 marks pre-poost test with newtoon 1st law and 3rd law and total scores
Using pree-test scores plotted versuus normalizedd gains (Figuure 12), the trend
t
of highher normalizeed gains <g>
> =
%
across 0 too 7 out of maxximum 11 maarks range of ppre-test scoress for the experrimental groupp the emergedd as
%
w
well.
%
100% hake's 90% gain
Experimen
ntal
Control
Linear (Exp
perimental)
Linear (Control)
80%
70%
60%
50%
y = ‐0.0513x + 0.6583
40%
30%
20%
y == ‐0.0516x + 0.55
10%
0%
0
1
2
3
pre‐test scores
4 5 6 7
8
9
10 11
Figure 12. Grraph of pre-test sccores of both expeerimental (N=45) and control (N=445) groups versus hake’s normalizzed gain <g> =
%
100
%
%
off
students for thhe maximum scorees of 11 marks w
with marks 8 to 111 omitted from annalysis due to negaative hake’s gain but it does not addversely affect thee
overall trend.
IV
V.
DISCUSSSIONS
A
A. RVHS
We includde excerpts from the qualitattive survey ressults and inform
mal interview
ws with the studdents to give ssome themes aand
iinsights into the
t conditionss and processees during the laboratory lessons. Words in brackets < > are addedd to improve tthe
rreadability of the qualitativee interviews.
i key to learnning
1) Active aand interactivve engagment is
“I felt good learning thiss way because it facilitated aand encourageed discussion inn groups, and ultimately alloowing us to haave
ddeeper impresssion of certainn concepts. It was a good eexperience andd I feel I gainned more from
m this lesson thhan from reguular
<
<less interactive> classes. I feel that studeents should be given the linkk to download the tool after llessons for intteractive learniing
eeven at home, because this ggives students a more interessting way to reevise certain toopics”.
“The lessoon was one off the best methhods to actuallly be able to experiment aand witness firrsthand the ressults of differrent
kkinds of collission and is thuss pretty good.””
9/26
“I think we need more demonstration
d
videos or javaa programs beecause people llike me are visual learners aand an animatiion
w
will make learrning clearer.””
g
computerr model designn
2) Need good
“The compputer model deesign was brillliant and I enjooyed and undeerstood the conncept better wiith it.”
“The appleet provided ann easy to underrstand interface and allowedd for immediatee understandinng.
3) Need sttronger scaffoolds at the begiinning of lessoon
“The teachhers should usse the program
m to demonstrrate and explaain at the samee time. Not leetting us exploore, and "wondder
aaround".
“Explain thhe concepts firrst.”
“It only feels good whenn our predictioon and observaations matchedd. Otherwise w
we were most oof the time connfused.”
B
B. AJC
1) Hake’s Gain and thee rationale for removing datta with high prre-test
Hake’s gain i.ee. scored lowerr in the post teest. We removeed these studeents
Several stuudents in both groups obtainned negative H
ffrom the Hakee’s gain analyssis because of several reasonns.
a) increaased Hake’s gaain senstivity aat higher pre-test scores
We specullate the increaased sensitivitty at higher prre-test scores say 8 marks, to score say lower say, 6 marks, whichh is
ccomputed as =
200% , raised cooncerns about the validity of
o the test quuestions and students attituddes
ttowards comppleting the testss.
b) Studennts making willd guesses durring post test
We specullate some studdents are makinng wild guess during the poost tests suggessted from interrviews and absurdly short quuiz
ttime clocked oonline and perh
rhaps also the llack of challennge from samee questions in pre-post
p
test.
Thus, markks 8 to 11 (Figgure 12) were omitted from analysis resultting in our Hakke’s gain <g> analysis from
m 0 to 7 marks.
Although tthe Hake’s gaains <g> for thhe various pree test scores arre plotted and a general trennd emerged frrom the data tthat
ssuggests Hakee’s gains of thhe students in tthe Experimenntal group are higher than thhe control grooup, from the linear fit (Figuure
12) line.
m effect standaardized mean ddifference of 00.21 from expeerimental (N=662) and controol (N=67) grouups
Thus, withh both medium
aand the norm
malized gain annalysis of the trend lines exxperimental (N
N=45) and coontrol (N=45) groups and ttriangulated with
w
iinterviews witth students annd teachers, the evidences suuggest studentts did benefit from the expeerimental inquuiry based lessson
aachieving deepper learning thhan their peerss in traditional less interactivve classrooms.
V
V.
CONCLUSSIONS
The 9 com
mputer models derived from
m the Open S
Source Physiccs digital libraary are sharedd briefly givinng credits to the
ooriginal authoors and sub-autthors, so that ordinary teachhers like us arre able to standd on the shoullder of OSP ggiants and furthher
ccustomize ourr computer moodels to suit ow
wn syllabus annd learning conntext.
A
A. RVHS
s
and teeachers has beeen relatively ppositive, thus the teachers w
will be scaling up (Dede, 20007)
General feeedback from students
tthe use of otheer computer m
models with souund pedagogiccal approach.
B
B. AJC
m effect of stanndardized mean difference of 0.21 from experimental (N=62) and ccontrol (N=677) and the highher
A medium
nnormalized gaain analysis froom experimenntal (N=45) annd control (N=45) across pree-test scores suuggests that stuudents who haave
bbenefitted from
m the inquiryy based lessonn can achieve deeper learninng than their peers
p
in tradittional classroooms. In additioon,
10/26
ggeneral feedbaack from the students
s
has beeen relatively ppositive, trianggulated from sstudents’ surveey and focus ggroup interview
ws,
rreflections by teachers.
more teachers will find the simulation
s
useeful in their ow
wn classes andd further custoomized them so
s that others ccan
We hope m
aact more intellligible (Juuti & Lavonen, 20006) with them
m, benefiting aall humankind, becoming citiizens for the w
world.
ACKNOWLEDGEM
C
MENT
We wish tto acknowledgge the passionnate contributtions of Franccisco Esquembbre, Fu-Kwunn Hwang, Wollfgang Christian,
A
Andrew Dufffy, Todd Tim
mberlake and JJuan Aguirreggabiria for thheir ideas andd insights in tthe co-creatioon of interacttive
ssimulation andd curriculum materials.
m
This reseaarch is made possible thannks to the eduuLab project NRF2011-ED
DU001-EL0011 Java Simulaation Design for
T
Teaching and Learning, (MOE, 2012b) aw
warded by thee National Ressearch Foundaation (NRF), S
Singapore in coollaboration w
with
N
National Instittute of Educatiion (NIE), Sinngapore and thhe Ministry of E
Education (MOE), Singaporre.
We also thhank MOE foor the recognittion of our ressearch on com
mputer model lessons as a significant
s
innnovation in 20012
M
MOE Innergyy (HQ) GOLD Awards (MOE
E, 2012a) by E
Educational Teechnology Divvision and Acaademy of Singgapore Teacherrs.
Any opiniions, findings,, conclusions or recommenndations expreessed in this ppaper, are thoose of the autthors and do nnot
nnecessarily refflect the viewss of the MOE, NIE or NRF.
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Educaation Retrieveed 20 October,, 2010, from
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MOE. (2012a)). MOE Innerggy Awards: M
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m
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T
Timberlake, T
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masss-briefing-at-juurong-junior.hhtml
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http:///www.compaadre.org/Repossitory/documeent/ServeFile.ccfm?ID=11775&DocID=26634 &
http:///www.compaadre.org/osp/doocument/ServveFile.cfm?ID=
=11775&DocIID=2634&Atttachment=1 (ppublic
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Wee, L. K. (2012b). One-diimensional colllision carts coomputer modeel and its desiggn ideas for prroductive expeeriential
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m
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appleet, from http:///www.phy.ntnnu.edu.tw/ntnuujava/index.phhp?topic=24088.0
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Duffy, A., & H
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Wee, L. K., D
Duffy, A., & H
Hwang, F.-K. (22012b). Ejs O
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Gravitational Fiield & Potentiial of Earth annd Moon Java
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Wee, L. K., & Esquembre, F
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W
Wee, L. K., & Esquembre, F
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https://sites.googlee.com/site/lookkang/edulabgrravityearthanddsatelliteyjc/ejs_EarthAndSaatelite.jar?attreedirects=0&d=
=1
& htttp://www.phy.ntnu.edu.tw/nntnujava/indexx.php?topic=1877.0 (requirees Registrationn to downloadd)
W
Wee, L. K., Esquembre, F., & Lee, T. L. (2012). Ejs Oppen Source Loong Magnet Falling Througgh solenoid Moodel Java Appplet
by LT
TL, from http://www.phy.nntnu.edu.tw/ntnnujava/index.pphp?topic=23999.0
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with realistic ccollision from
m
W
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library to create innteractive digiital media for mass customizzation of high school physiccs curriculum. Paper presentted
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E. H., & Wee, L. K. (2011). Learning withh multiple reprresentations: aan example off a revision
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AUTHOR
12/26
L
Loo Kang Lawrence WEE iss currently an educational
e
technology speccialist at the Ministry
M
of
E
Education, Singgapore. He waas a junior colllege physics leecturer and hiss research inteerest is in Opeen
Source Physicss tools like Eassy Java Simulaation for desiggning computeer models and use of Trackeer.
A
Ai Phing LIM iis currently a teacher
t
in Rivver Valley High School, Singgapore. She haas over 14 yeaars
off teaching gradde 11 and 12 experience
e
andd has Masters in Science Edducation.
K
Khoon Song Alloysius GOH is currently a pphysics teacheer in Andersonn Junior Colleege. His
accademic and professional
p
innterests includee the appropriiate use of ICT
T to enhance leearning and
feeasibility of orrganization maanagement theeories in Singaapore’s public school system
m.
Szze Yee is currrently an educaational technoology officer inn Ministry of Education,
E
Sinngapore. She iis
a trained Physiccs Teacher andd had taught both
b
Physics annd science in secondary andd primary
Simulations foor physicsscchools. She is now working on modifyingg the Open Souurce Physics S
reelated topics inn primary schoool.
T
Tat Leong LEE
E is currently tthe Head of Deepartment for Education Technology in R
River Valley
H
High School, Singapore. He is a high school Physics teaacher, with 10 years of teachhing experiencce.
H
He has been using Open Souurce Physics (O
OSP) tools as early
e
as 2006 (Tracker and E
Easy Java
Siimulations).
W
Weiming XU iss currently thee Acting Subjeect Head for Educational
E
Teechnology in R
River Valley
H
High School, Singapore. He is a high school Physics teaacher with a paassion and inteerest in
inntegrating mulltiple modes of representatioon of informattion in the teacching of Physiics to provide
auuthentic and m
meaningful leaarning experiennces.
.
G
Giam Hwee Jim
mmy GOH is ccurrently the H
Head of Sciencce Departmennt in Yishun Juunior College,
13/26
Siingapore. He tteaches Physiccs to both yearr 1 and 2 studeents at the college and advoocates inquiry-baased science teeaching and leearning througgh effective annd efficient meeans.
C
Chee Wah ONG
G is currently a senior teachher teaching inn Innova Junioor College, Sinngapore. He haas
ovver 16 years oof experience tteaching gradee 11 and 12 annd has a Masteer degree in Sccience.
Soo Kok, NG iss currently teaaching in Innova Junior Colllege. He has 23
2 years of teaaching
exxperience and a keen advocate of experienntial learning.
E
Ee Peow LIM iis currently teaaching in Andderson Junior C
College, Singaapore. He is leeading a Physics
IC
CT Resource T
Team of teachhers. Before that, he obtainedd a distinctionn in pre-servicee teaching
prracticum with his creative teeach methods..
C
Chew Ling LIM
M is currently teaching Physsics in Serangooon Junior Coollege, Singapoore. She has 7
yeears of teachinng experience..
W
Wee Leng Joshhua YEO is cuurrently teachinng Physics in Serangoon Junnior College, Singapore. Hee is
allso one of the College’s ICT
T Mentor speaarheading the iinitiative to creeate a critical mass of
teeacher advocattes or champioons to developp and cascade effective ICT practices.
14/26
M
Matthew ONG is currently ann educational technology offficer in Minisstrhy of Educaation, Singaporre.
H
He has experiennce teaching inn the grade 1 tto 6.
K
Kenneth Y T L
LIM is a Reseaarch Scientist aat the Office oof Education R
Research, Natioonal Institute of
E
Education. His present researrch interests arre in the affordances for leaarning that imm
mersive
ennvironments ooffer. Throughh his research, he is developiing a theory of learning arouund the conceppt
off Disciplinary Intuitions.
VI.
Subject:
Level:
Worksheet Title:
T
APPEND
DIX A: WORKS
SHEET WITH SU
UGGESTED ANS
SWERS BY RV
VHS
Physics
Time: 1h 15 min
A-Level
Virtual Laboraatory
P06 – Collisiions between ttwo bodies – V
Apparatus List
01 × laptop
In this practtical you will investigate thhe dynamics of collisions with TIPERs w
worksheets usinng the easy Jaava simulationn
ejjs_users_sgeduucation_lookaang_Momentum
m1D2010webb02.jar.
The followiing sections coonsist of variouus collision scenarios.
Read througgh the context carefully befoore making an educated guesss as to the outtcome. Explaiin your reasonning.
Finally, runn the simulationn to verify youur prediction.
me and the sim
mulated outcom
me identical? If they are nott, explain the ddiscrepancy.
Are your prredicted outcom
How to use the Virtual Laaboratory
Select the tyype of collisionn by clicking the
t radiobuttonn
.
Key in the m
masses of the ccart 1 and presss the enter keyy. Repeat for ccart 2
Key in the iinitial velocityy of cart 1 and press the enterr key. Repeat ffor cart 2.
Click the play button
to start the simulation.
mulation by cllicking on
Reset the sim
reset buttoon.
You may w
wish to explore other featuress such as graphhs in your ownn free time.
E.g.: e is thhe coefficient of restitution and it is the raatio of speeds after and befo
fore an impact,, taken along the
t line of thee
im
mpact (i.e. a m
measure of how
w much kineticc energy is lostt).
15/26
(a)
Carts A and B are shown juust before theyy collide.
No other info
formation is giiven. Don’t Assk. 
wing contentionns:
Four studentss discussing thhis situation maake the follow
off to the left. Cart
C B has moore speed, andd
Eugene: “Afteer the collisionn, the carts wiill stick togetheer and move of
its speed is goingg to determine which cart doominates in thee collision.”
Sean: “I thinnk they’ll stickk together andd move off to the right becaause Cart A iss heavier. It’’s like when a
j because itt’s heavier.”
heaavy truck hits a car: The trucck is going to win no matterr which one’s ggoing fastest, just
mass compensate, and the carts are goiing to be at rest after thee
Thomas: “I think the speed and the m
colllision.”
Meili: “The ccarts must havve the same moomentum afterr the collision as before the collision, andd the only wayy
thiss is going to happen
h
is if they keep the saame speeds. All
A the collisioon does is channge their direcctions, so thatt
Cart A will be mooving to the lef
eft at 3 m/s andd Cart B will be
b moving to thhe right at 4 m/s.”
m
Which, if anyy, of these fourr students do yyou agree withh?
Thomas ______ Meili ______ None of them
m______
Eugene______ Sean _____ T
Explain.
Answer: N………………
one of thes
…………………
se contentio………………
ns is correc
…………………
ct. We do no
ot
………………
have eno
…………………
ugh informa
ation
……. to
………………
of either ca………………
d
determine
t………………
he velocity…………………
rt after the…………………
ccollision. Mo
omentum
w
will
be conse
erved
………………
…………………
……. for
………………
ion, but this
s could happ
pen
in a num
mber of wayys,
such as…………………
tthe carts sti…….
icking
the collisi………………
…………………
………………
…………………
………………
………………
together a
and
remainin
ng at rest, or
o………………
the carts…………………
bouncing of………………
ff one anoth
her. What ac
ctually
………………
…………………
…………………
…….
………………
ction of the…………………
happens d………………
epends on…………………
the construc
carts and o
on
the mater
rial of the su
urfaces
………………
………………
…………………
…….
………………
………………
…………………
………………
…………………
………………
…………………
…….
………………
16/26
(b)
Two identicaal carts travelling in opposiite directions are shown juust before theyy collide. Thee carts carry
diff
fferent loads annd are initiallyy travelling at ddifferent speedds. The carts sttick together aafter the collisiion.
Three physicss students disccussing this sittuation make tthe following ccontentions:
Sherwin: “Thhese carts will both be at resst after the colllision since thee initial momeentum of the syystem is zero,
mentum has too be zero also.””
andd the final mom
k
energy after the collission and that
Sunny: “If thaat were true itt would mean that they woulld have zero kinetic
would violate connservation of energy.
e
Since the right-handd cart has morre kinetic energgy, the combinned carts will
be moving slowlyy to the left aftter the collision.”
Steven: “I thhink that afteer the collisioon the pair off carts will bbe traveling leeft at 20 cm//s. That way
connservation of m
momentum andd conservationn of energy aree both satisfiedd.”
Which, if anyy, of these threee students do you think is coorrect?
Sherwin ______ Sunny ______ Steven ______ None of thhem______
Please explain your reasoniing.
Answer: S
Sherwin
is…………………
c
correct.
The
e………………
momentum
m of the two
o………………
carts are …………………
e
equal
and op
pposite
………………
…………………
…….
………………
mentum
before the………………
collision, so
o the total in
nitial
momen
ntum is zero
o………………
and the to
otal final mo…….
…………………
………………
…………………
…………………
………………
has to be …………………
zero also. ………………
………………
…………………
………………
…………………
…….
………………
………………
…………………
………………
…………………
………………
…………………
…….
………………
………………
…………………
………………
…………………
………………
…………………
…….
………………
………………
…………………
………………
…………………
………………
…………………
…….
………………
17/26
(c)
In Case A, a m
metal bullet peenetrates a woooden block.
In Case B, a rubber
r
bullet w
with the same initial speed aand mass bounnces off an idenntical woodenn block.
No other info
formation is giiven. Don’t Assk. 
Case A, greateer in Case B, oor the same in
Will the speeed of the woodden block afterr the collision bbe greater in C
botth cases?
Explain.
A
Answer:
Gre
eater
for B.…………………
The initial m
momentum
in both case
es is the sa
ame and poiints
………………
………………
…………………
………………
…………………
…….to the
………………
bullet point
right.
The fin
nal momen
tum of the ………………
ts to the rig
ght
in Case
e A and to …….
tthe left in
………………
…………………
…………………
………………
…………………
………………
ce the final
momentum
e block is
C
Case
B. Sin………………
m………………
of the syst
tem consistting
of the …………………
b
bullet
and th…….
…………………
…………………
………………
………………
th
he
same as
s the initial
momentum
m,
and this…………………
final mome
entum
is th
he vector su
um
………………
…………………
………………
………………
…………………
…….of the
………………
of the bulle
momentum
the block
m
momentum
et and the ………………
of the blocck,
the mom
mentum of …….
………………
…………………
…………………
………………
…………………
………………
m
must
be grea
ater in Case
e B.
………………
…………………
………………
…………………
………………
…………………
…….
………………
Will the speeed of the bulleet in Case B affter the collisioon be greater than, less thann, or the same as the speed
of the
t bullet just before the colllision?
Explain.
A……………
Lesss
than. The
e……………
energy of the
containing
both block
ccannot be
system ……………
and bullet…………….
…Answer:
……………
……………
………………
………………
g……………
afterr……………
the collision
ore.
The initial
c energy of…………….
tthe bullet,
than befo
energy………………
iss the kinetic
…greater
……………
………………
……………
……………
the kinetic energies
a……………
the finall……………
energy is tthe
sum of ……………
off the bullet………………
a
and the blo
ock. Since
…and
……………
………………
…………….
……………
he
block hass……………
a non-zerro
final kinettic
energy, tthe
final kine
etic energy
of the bulle
et must be
…th
……………
………………
………………
…………….
……………
……………
……………
le
ess than the
e initial kinettic energy o
of the bullet.
18/26
Half Way Check Point
For each of thhe earlier situaations (a) to (c), answer the ffollowing quesstions.
e
on thee system.
List all the exxternal forces exerted
Does the systtem have an innitial momentuum? Describe any changes iin its total mom
mentum.
Does the systtem experiencee a net impulse during the sppecified time pperiod? Explaain.
(a)
1.
Assume friction is
gligible.
neg
 weight of sy
ystem
ction
 normal reac
force on sysstem
2. Initially, the system has zero m
momentum. The total m
momentum d
does not change
……………………………………………………………………
………………
………………
…………….
with time
e. Or rather, the chang
ge in momentum is zero
o.
……………………………………………………………………
………………
………………
…………….
3. There is
s no net imp
pulse deliverred to the syystem. The
e gravitational and norm
mal forces
……………………………………………………………………
………………
………………
…………….
balance.
……………………………………………………………………
………………
………………
…………….
(b)
1.
Assume friction is
gligible.
neg
 weight of s
system
 normal rea
action
force of sysstem
does not cha
. Initially, tthe
system has
zero mo
omentum.
The
total ………………
momentum………………
ange with
……………
……………
……………T
…2……………
……………
…………….
is zero. ………………
time. Orr……………
rather, the ……………
change in m
momentum
………………
………………
…………….
…………………………
gravitationa
no net impu
. There is ……………
ulse
delivere
ed
to the syystem.
The
al and norm
mal forces
…3……………
……………
………………
………………
…………….
……………
……………
balance.……………………………………………………
………………
………………
………………
…………….
 w
weight of wo
ooden
b
block
 n
normal reacction
fforce on wooden
b
block
 w
weight of bu
ullet
19/26
(c)
1.
Assume friction is
gligible.
neg
2. Initially, th
he system has momenttum. The to
otal momenttum does no
ot change with
w
……………………………………………………………………
………………
………………
…………….
time. Or rrather, the change
c
in momentum
m
iss zero.
……………………………………………………………………
………………
………………
…………….
no net impullse delivered
d to the sysstem. The g
gravitationall force on th
he bullet
3. There is n
……………………………………………………………………
………………
………………
…………….
causes a small verticcal downwarrd change in
n momentum
m of the bullet, which iss
……………………………………………………………………
………………
………………
…………….
negligible.
20/26
Extendingg Your Underrstanding
(e)
Two identicaal steel balls, P and Q, are shhown at the innstant that theyy
colllide.
The paths annd velocities of the two balls before and after thee
colllision are indiicated by the ddashed lines annd arrows.
The speeds of the balls are same before and
a after collission.
For the questtions below, uuse the directioons indicated by the arrowss
in tthe direction rrosette, or use J for no direcction, K for innto the page, L
forr out of the pagge, or M if nonne of these are correct.
m for ball Q?
Which letter bbest represents the directionn of the changee in momentum
Explain.
A
Answer:
A. ………………
e in velocityy………………
of ball Q…………………
is its final vvelocity
min
nus its initia…….
l velocity,
The change
…………………
………………
…………………
………………
a
and
is found
d………………
by subtrac
cting vectorss………………
as shown.
………………
…………………
…………………
………………
…………………
…….
………………
………………
…………………
………………
…………………
………………
…………………
…….
………………
………………
…………………
………………
…………………
………………
…………………
…….
………………
………………
…………………
………………
…………………
………………
…………………
…….
………………
………………
…………………
………………
…………………
………………
…………………
…….
m for ball P?
Which letter bbest represents the directionn of the changee in momentum
Explain.
l velocity,
A
Answer:
E. ………………
The change
e in velocityy………………
of ball P…………………
is its final vvelocity
min
nus its initia…….
…………………
………………
…………………
………………
a
and
is found
d………………
by subtrac
cting vectorss………………
as shown.
…………………
…………………
………………
…………………
…….
………………
………………
…………………
………………
…………………
………………
…………………
…….
………………
………………
…………………
………………
…………………
………………
…………………
…….
………………
………………
…………………
………………
…………………
………………
…………………
…….
………………
……………………………………………………………………
………………
………………
…………….
21/26
Choose the leetter that best rrepresents the direction of thhe initial mom
mentum for the system of botth balls P and
Q bbefore collision.
Explain.
A
Answer:
C
C.
The initia
al moment………………
system is………………
the vecto
or sum of …….
tthe initial
um of the…………………
………………
…………………
…………………
………………
ed togetherr,
m
momentum
of the indiv
vidual balls.………………
these mo
omentum po
oint
When add
………………
…………………
…………………
………………
…………………
…….to the
………………
as show
right
wn.
………………
…………………
………………
…………………
………………
…………………
…….
………………
………………
…………………
………………
…………………
………………
…………………
…….
………………
………………
…………………
………………
…………………
………………
…………………
…….
………………
………………
…………………
………………
…………………
………………
…………………
…….
………………
Choose the leetter that best rrepresents the direction of thhe final momeentum for the system of bothh balls P and
Q aafter collision.
Explain.
A
Answer:
C.………………
The final …………………
m
momentum o
of
the syste
m is the ve………………
ctor sum of
f the final m
momentum
………………
…………………
…………………
…….
………………
o
of………………
the indivi………………
idual balls.
When add
ded
togethe
er, these momentum
m………………
p
point to the
e…….
right as
…………………
………………
…………………
…………………
sshown.
Note
e………………
that since
e momentum
m
is conserv
ved for this………………
system, th
e final mom
mentum
is
…………………
………………
…………………
…………………
…….
………………
initial mome
e
equal
to the………………
entum.
…………………
………………
…………………
………………
…………………
…….
………………
………………
…………………
………………
…………………
………………
…………………
…….
………………
………………
…………………
………………
…………………
………………
…………………
…….
………………
Choose the leetter that bestt represents the direction off the impulse during
d
this intteraction for thhe system of
botth balls P and Q.
Explain.
e is no imp
A
Answer:
J.………………
There is …………………
n
no direction………………
since ther
pulse
on th
e system d
during
…………………
………………
…………………
……. the
………………
no extern
nteraction.
There are ……………
nal
forces, ……………
and so ………………
no impulse
and no …………….
c
change
in
…in
…………………………
……………
………………
momentum
the syste
em.
…m
………………
………………
…………….
……………ffor
……………
………………………………………
……………………………………………………………………
………………
………………
…………….
22/26
VII. APPEN
NDIX B: WORK
KSHEET WITH S
SUGGESTED AN
NSWERS BY AJJC
Experimennt 1
Glider A iis launched towards and colllides inelasticcally with a sttationary glideer B on a smoooth plane. Affter the collisioon,
gglider A reverrses direction. The mass of gglider A, m is oone fifth the mass
m of glider B
B.
Given the conditions aboove, attempt thhe Java simulaation with diffe
ferent values off initial velocities.

v Bi  0

v Ai
B
A
A
A

v Bf  ?

v Af
B
A
A
f
diaggrams for each glider and forr the system S of the two gliders at an instant
In the spacce provided, drraw separate free-body
dduring the colllision.
F
Free-body
diaagram for glideer A
F
Free-body diaggram for gliderr B
R
FA
R
A
Freee-body diagraam for system
m
S R
FB
B
MBg
MAg
S
MSg
(B) How
w does the net force on glideer A, FA, com
mpare to the neet force on gliider B, FB, at this instant? D
Discuss both tthe
m
magnitude andd direction of tthe net force.
The magniitude of FA is greater than / equal to / smaaller than the magnitude
m
of FB.
F
The directiion of FA is saame as / oppossite to the direection of FB.
F-t graph (Figuure 1) below sshows the net force
f
FA actinng on glider A during the colllision. On Figgure 1, sketch tthe
(C) The F
vvariation with time t of net fforce FB actinng on glider B.
F/N
t/s
Figure 1
at can you sa
ay about the n
net force actiing on glider B
(A) Wha
(i) before collission zero
FB (eq
qual to FA)
(ii) during collission
on
zero
(iii) after collisio
23/26
Now, conssider the time interval whilee the gliders arre still in contaact during the collision to bee Δt. How doees the product FA
Δ
Δt compare too the product FB Δt? Discuss this in terms of
o the magnituude and directiion.
e
to FB inn magnitude aand opposite iin direction, FA Δt and FB Δt are equal in magnitude and oppositee in
Since FA equal
ddirection.
∆
wton’s secondd law (for connstant mass)
m to each of the glliders to comppare the changge in momentuum
Apply New
∆
((Δp=mΔv) of gliders A and B during the collision.
c
Disccuss both the m
magnitude andd direction of thhe change in momentum.
m
The magniitude of the chhange in momeentum of glideer A is greater than / equal too / smaller thaan the magnituude of the channge
iin momentum
m of glider B.
m of
The direction of the chaange in momenntum of gliderr A is same as / opposite to tthe direction oof the change in momentum
gglider B.
The area uunder an F-t ggraph represennts the changee in momentuum of a body. Hence, on Figure
F
2, sketcch correspondiing
m
momentum-tim
me graphs for
glider A
glider B
m
momentum/N s
B
time/ss
A
Figure 2
um-time grap
ph for glider B after the co
ollision.
Describe the momentu
mentum-time g
graph for glid
der B after co
ollision is a straight horizon
ntal line.
The mom
ur answers to
o D (iii) and H
H, what can yyou say about the velocityy of glider B d
during this pe
eriod?
Using you
nstant. (No ne
et force, no change
c
in mo
omentum)
The veloccity of glider B during this period is con
24/26
E
Experiment 2

v Ci

v Ai

v Cf  ?

v Af
C
A
A
C
A
A
G
Glider A is noow launched w
with a momenttum of 200 kgg m s-1 towardds glider C whhich is movingg in the opposiite direction w
with
a momentum of 50 kg m s¬
¬-1. After the iinelastic collission, glider A reverses direcction. The masss of glider A is 25 kg and tthe
m
mass of gliderr C is 40 kg. T
The coefficientt of restitutionn e for this colllision is 0.8977.
((A)
In thee space providded, draw sepaarate free-body
dy diagrams foor each glider and
a for the sysstem S of the ttwo gliders at an
iinstant during the collision.
Free-bodyy diagram for gglider A
Free-body diaagram for glidder C
R
FA
A
MAg
R
Freee-body diagram
m for system S
R
FC
C
MCg
S
MSg
A, FA, comparre to the net force on glideer C, FC, at tthis instant? D
Discuss both tthe
How doess the net forcee on glider A
m
magnitude andd direction of tthe net force.
The magniitude of FA is greater
g
than / equal
e
to / smalller than the m
magnitude of FC.
The directiion of FA is sam
me as / opposiite to the direcction of FC.
Discuss thhe magnitude aand direction oof the change inn momentum.
The magnnitude of changge in momenttum of glider A is greater thhan / equal too / smaller thaan the magnituude of changee in
m
momentum off glider C.
The directiion of change in momentum
m of glider A iss same as / oppposite to the diirection of chaange in momenntum of gliderr C.
from the Java simulation,
s
filll in the final m
momentum off glider A and complete the momentum-tim
me
Using valuues obtained fr
ggraph of glider C with an apppropriate valuue.
25/26
momentum
m/kg m s-1
20
00
10
00
0
gliderr C
-10
00
-5
5
final momen
ntum of A = _-70_
_
kg m s-1_
glider A
0
time/ms
5
Mome
entum/kg m s-1
220
200
2
200
100
100
1
0
0
-100
200
--100
100
g
glider C
-1
glider A
0
1
-70
ttime/ms
Thinking Questions
Commentt on the veloccities of the bodies
b
after th
hey collide elastically for tthe following situations:
1.
2 identical masses colliding.
ennis ball inciident on a wa
all
2.
A te
3.
A bo
owling ball in
ncident on a stationary
s
tab
ble tennis ball.
Use the JJava simulatio
on to confirm
m your results.
Adapted frrom Tutorials in Introductorry Physics
Mc Dermoott, Shaffer, & P.E.G., U. Wash.
W
©Prenntice Hall, Incc.
First Edition, 20022
26/26

Comp puter Mod dels Design n for Teac ching and L Learning u

Transcription

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