Download Proposal-Use

1
Dissertation Proposal
Title: Applying electromagnetism to develop demonstration sets for enhancing students’
conceptions in Newton’s laws
Candidate: Thanida Sujarittham
Committee:
1. Assist.Prof.Dr. Narumon Emarat
2. Assist.Prof.Dr. Kwan Arayathanitkul
3. Dr. Tussatrin Kruatong
Date: November 8th, 2008
Time: 9:00 a.m.
Room: RF5
Abstract
In this study, we present the sets of demonstration that we developed and used in a
physics class for Thai high-school students. The demonstration sets comprise two main
parts: (1) simple motion demonstration (2) complicated motion demonstration. In the
second part, tools that required knowledge in electromagnetism were used for teaching
non-uniform forces. We brought a magnet and a solenoid to create and show forces
between them. We carry out the demonstrations with microcomputer-based laboratory
(MBL) measurements. The results could be immediately displayed on the screen in front of
the class using an LCD projector. This teaching method is called the interactive lecture
demonstration (ILD) 1 and is aimed to engage students to learn as well as to help them
integrate their knowledge to new situations. The demonstration sets were planned to use
with high-school students who have already learned basic topics on force and motions.
2
In the pilot study, the demonstrations were conducted with high-school students
of grade ten. To evaluate this teaching-learning method the Thai version of the Force and
Motion Conceptual Evaluation (FMCE) 2 test was given to the students before and after the
teaching process. It was found that the average normalized gain 3 of the students was 0.20.
The highest gain was in the Newton’s third law. These results suggest that the set of
demonstrations can help develop students’ conceptual understanding in force and motion.
1. Introduction
Physics educations research in conceptual understanding section exhibited that
Mechanics area had been one of the most interesting topics for over twenty years. The
content areas that students found difficult are kinematics, dynamics and relativity and
frame of reference 4 . Issues of alternative conceptions of students in mechanics are their
experiences. Many researchers found that students began to learn physics from common
beliefs 57 . This phenomenon has caused a growing trend to develop and to assess students’
understanding.
1.1 Misconception of students in dynamics
What causes the motion of an object? Why is the object moving? These questions
relate to Newtonian physics. Newton’s laws of motion have three statements. For the first
law, if the net force acting on an object is zero, it moves with a constant velocity. For the
second law, if there is a net force acting on an object, it moves with an acceleration. The
directions of the force and the acceleration are similar while the magnitudes are related,
that is, the acceleration equals to the net force divided by mass of the object. The third law
relates to action and reaction forces, that is, when one object exerts a force on a second
object, the second object exerts an equal and opposite force on the first object 89 .
3
Thornton (1995) reported various student views in analyzing physical situations
and found that they were different from physicist views. Results of students’ views taken
from individual interview and responses to the Force and Motion Conceptual Evaluation 2
were explicit. In the first case, an object is moving with a constant velocity, most students
viewed that there was a non-zero net force acting on the object in the direction of motion.
Some students think that the net force will decrease in the direction of motion. In the
second case, an object is moving and speeding up at a steady rate. For this situation, most
of the students answer that the net force is increasing at a steady rate in the direction of
motion. In the third case, an object is moving and slowing down at a constant rate. Most
students view that the net force is decreasing at a constant rate. The common
misconception found was that the students thought the force is behaving like the object
velocity.
Bao et al. (2002) had studied students’ model on Newton’s third law of motion by
using open-ended interview questions which included the “contextual feature” of velocity,
mass, pushing and acceleration. From the responding of the students, some misconceptions
were found. For the feature of velocity, if an object is moving with a large velocity, it will
exert force more than the object with a small velocity. For the mass feature, when two
objects collide, the heavier object exerts a larger force.
According to our preliminary work with Thai high-school students, we found
similar results. Most students had misconceptions in Newton’s laws of motion. For
example, some students could answer that they knew about action-reaction forces that had
equal magnitudes and opposite directions. However, when they were asked about the
collision of two cars, their answers opposed the Newton’s third law.
4
1.2 How to teach Newton’s laws of motion
Physics instructors shared a common interpretation of kinematics and dynamics
based on operational definitions and precise verbal and mathematical articulation 12 . Some
instructors prepared laboratories or experiments for teaching and probing the Newtonian
motion conceptions. They employed a microcomputer 6,10 that could show the graph of
position, velocity and acceleration as a real-time graph. There are many other teaching
approaches designed for kinematics and dynamics instruction. One of the effective ways is
the Interactive Lecture Demonstration.
Interactive Lecture Demonstration (ILD) 1 is a well-known approach for teaching
force and motion. This approach promotes an active learning environment in a lecture. One
of the main strategies of the ILD uses MBL or Microcomputer-based laboratory for
displaying real-time data.
In Thailand, Jairuk (2007) conducted a research about the use of interactive lecture
demonstrations in force and motions. He found that the ILD could help students improve
the conceptions quite better than the traditional lecture.
Tanahong (2008) studied the development of students’ conceptions of heat and
temperature using the interactive lecture demonstration. His results showed that the average
normalized gain of students who had participated in the ILD classroom was greater than the
traditional classroom.
1.3 The step of ILD:
1. The instructor describes the demonstration (does not display the results).
2. The students are asked to record their individual predictions about the demonstration.
(The students are assured that these predictions will not be graded.)
3. The students discuss their predictions with their peers.
5
4. The instructor exhibits some of the initial students’ thinking.
5. The students record their final predictions.
6. The instructor displays the results that are measured with micro-computer-based on
LCD.
7. The instructor asks 2-3 students to describe the results.
8. The instructor discusses about the demonstration and indicates the conception from
the demonstration as well.
1.4 Demonstration tools designed by using electromagnetism
The motivation of the research was constructed from the Maglev vehicle. Its
motion is caused by the magnetic force. Many schools had used a Maglev system as a
demonstration to engage students in a classroom. Dart (1985) adapted the magnetic
laboratory from Saraf et al. (University of Rajasthan) for teaching in the energy concept.
The repulsive forces between two magnets were used in the demonstration. While one
magnet is at rest, the other is attached with the glider which moves on the air track. They
measured the potential energy by using the photogate. Kraftmakher (2008) set up an
experiment for teaching Electromagnetic force. He showed the lift force of the magnet
which can be measured by the force sensor.
We surveyed many research for constructing the demonstration sets. Bednarek
(1992) made a magnetic track for experiments in mechanics. Aguilar (2007) used a
magnetic levitation for teaching the Newton’s third law. Students could learn about actionreaction forces that occurred from the levitation force. A solenoid was placed on a scale,
and then a steel ball was placed on top of it and the ball floated on a scale. Students could
observe the increasing of the values on a scale. These are some ideas for construction of the
demonstration sets in this study.
6
2. Research objectives
The objectives of this study are as follow.
1. To investigate the prior knowledge of students in Newton’s laws of motion.
2. To enhance students’ understanding in Newton’s laws of motion.
3. To develop the demonstrations sets for teaching Newton’s law of motion with the
interactive lecture demonstration teaching approach.
3. Research questions
1. What are students’ prior knowledge about the Newton’s laws of motion?
2. Can the demonstration sets improve students’ understanding in Newton’s laws of
motion?
4. Statement of proposal
Applying electromagnetism to develop demonstration sets for enhancing students’
conceptions in Newton’s laws of motion.
5. Research Methodology
5.1 Phase 1: Survey students’ understanding in Newton’s laws
We investigated pre-conceptions of 350 high-school students. 20 items of the
FMCE were used to probe students’ conceptions in Newton’s laws of motion. In addition to
this conceptual test, we used students’ prediction sheets as a guideline to the interview. We
could indicate the current misconceptions of the students. From this survey, we have
received some ideas to design the demonstration sets for helping students learning in
Newton’s laws.
7
5.2 Phase 2: Design Tools
- The demonstration sets
Our ideas for designing the demonstration sets were divided into two main parts: (1) the
demonstration set for teaching about a uniform force, and (2) the demonstration set for teaching
about a non-uniform force. All demonstration sets were designed for one dimensional motion.
The knowledge of Electromagnetism was used to create demonstration tools. The detail of each
demonstration set is explained in the following.
Table 1: Demonstration set of Newton’s first law
Demonstrations
Objectives
Situations
To teach about an object The
moving
with
a
object
constant released
is
pushed
(negligible
and
friction)
velocity. A net force and an then it will move away from the
acceleration are zero.
To teach about the moving
direction of the object and to
confirm about the zero force.
motion sensor.
The
object
released
is
pushed
(negligible
and
friction)
then it will move towards the
motion sensor.
To teach students about the The object is at rest when the
net force and the applied equal magnetic forces from two
force acting on the object.
solenoids act on it in both sides.
The demonstrations for teaching Newton’s first law are somewhat covering all
issues in this topic. In case of an object that is at rest, most students answered in the preconceptual test that there is no applied force acting on the object. To emphasize this fact,
the third demonstration is more obvious to students than the others. There are forces acting
8
on the object but the object is still at rest. This is because the two forces are equal and have
opposite directions and therefore the net force is zero.
Table 2: Demonstration set of Newton’s second law
Demonstrations
Objectives
Conditions
To teach about an object
moving with an increasing The object moves (with no
velocity at a steady rate. The frictional force) away from the
net force is positive and motion sensor due to a fan unit.
constant.
To teach about an object
moving with an increasing The object moves (with no
velocity at a steady rate. The frictional force) towards the
net force is negative and motion sensor due to a fan unit.
constant.
To teach about an object The
object
is
pushed
and
moving with a decreasing released so that it moves (with
velocity at a steady rate. The no frictional force) away from
net force is negative and the motion sensor while a fan
constant.
unit flows at all time.
9
The object is attached with a
magnet at one end. Push and
release the object to move
towards a solenoid. When the
students object gets closer to the solenoid
thinking of describing a non- there will be a repulsive force
uniform force (magnetic between the solenoid and the
force)
that
causes
a magnet.
To
encourage
complicated motion.
Reverse the direction of the
solenoid and an attractive force
will occur. Then push and
release the object to move
towards the solenoid.
The demonstrations 4, 5 and 6 as shown in Table 2 are generally used to teach in
the case of a uniform force. The demonstrations 7 and 8 are used to teach in complicated
motions. The magnetic demonstrations may seem difficult to predict and to describe for
students. However, if students have sufficient basic concepts, they will be able to
understand.
The advantage of demonstrations in the magnetic parts is that they can enhance
students’ thinking skills. The process of their thinking is ordered and revised again when
they have to describe these situations using the Newton’s first and second laws. A noncontact force is displayed. Students do not have much experience about these situations.
These may be called “New situations” for students.
10
Table 3: Demonstration set of Newton’s third law
Demonstrations
Objectives
Conditions
The glider A is heavier than the
glider B. Magnets of the same
To
teach
about
the polar are attached on each of the
magnitude and the direction glider. The gliders are then
of the action-reaction forces.
pushed with the same initial
speed then they will collide
without contact.
The current is applied to the
To teach about the action- solenoid then the magnet is
reaction forces between a dropped through the transparent
magnet and a solenoid.
rod above the solenoid. The
magnet levitation occurs.
In table 3, the demonstrations 9 and 10 are used to teach the third law of motion.
The magnitude and the direction of the action-reaction forces are displayed immediately to
make students belief in this law. Moreover, the teaching about the free body diagram is also
added in this teaching module.
Students will be surprised by the action-reaction force between the magnet and the
solenoid. They will understand that Newton’s third law can also occur for non-contact
forces.
11
- The conceptual test
We evaluated students’ understanding in two parts; the uniform force and nonuniform force. For the first part, we chose 20 items from the Force and Motion Conceptual
Evaluation (FMCE) that was translated into Thai by Emarat et al. 19 For the second part, we
constructed 14 items based on the FMCE. All questions were used as a pre-test and posttest.
- The prediction sheets
In the teaching process, we display the results of the demonstration by using graphs.
The prediction sheets are separated into 3 main parts. The first part describes the detail of
the demonstration. The second part contains empty graphs consisting of velocity-time,
acceleration-time and net force-time graphs. Each graph will be sketched (or predicted) by
students after they observe an experiment. In the last part students will explain the graphs
which they draw. Figure 1 shows an example of the prediction sheet.
5.3
Figure 1: An example of the prediction sheet
12
Phase 3: Try out the demonstration tools for improvement
The goal of this phase is to improve all instruments and to modify the teaching
process, for example, the speech of the instructor, the period of instruction, the contents
and concepts, and the demonstration sets. Every one of these needs to be carefully
examined.
We brought the tools to trial using and teaching with many groups, including
-
250 first year students,
-
30 junior Olympiad students,
-
20 postgraduate physics education students, and
-
12 postgraduate science education students.
After we thought that every thing was ready, we then carried out a preliminary study to see
whether it can help improve student understanding as we expected.
- Preliminary results
We used the demonstration tools to teach 34 high-school students with the ILD
approach. All of them had learnt mechanics before.
Normalized gains of Traditional teaching, J airuk's IL Ds
and IL Ds in this s tudy
Normalized gains
0 .8
0 .7
0 .6
0 .5
0 .4
TDL
0 .3
0 .2
IL D s ( T h is s t u d y )
IL D s ( Ja ir u k )
0 .1
0
1 s t& 2 n d ( n a tu r a l
la n g u a g e )
1 s t& 2 n d ( g r a p h )
3 rd
Figure 2: Normalized gains of students taught with traditional teaching, Jairuk’s ILD (2007)
and the ILD of this study
13
Figure 2 shows the normalized gains of different groups of students taught with
different methods. The graphs are grouped by each conceptual area of Newton’s laws
according to Jairuk (2007). It can be seen that the normalized gains of ILD instruction
are higher than the normalized gains of the traditional instruction. Our ILDs provides
higher gains than the traditional instruction in all concepts and higher than Jairuk’s ILDs
in Newton’s first law and second law. These results suggested that our ILDs were more
effective than Jairuk’s ILDs, especially in those concepts. On the other hand, the
normalized gain in Newton’s third law was lower than Jairuk’s one. This may be due to
the fact that at that time our ILD in Newton’s third law was still under the construction.
However, the normalized gain of this concept was in the medium level (0.34) and was
the highest amongst all.
5.4 Phase 4: Use the demonstration tools with sample group
The sample group in this study is 4 classes of tenth-grade high school students.
Three classes are from the school in Bangkok and the other class is from the school in
Lopburi. The total number of students is 150.
5.5 Teaching plan
We plan to collect data and teach students Newton’s laws of motion using our
demonstration sets with the ILD approach for 6 periods per class. The detail of teaching
and collecting data is shown in table 4.
14
Table 4: Teaching plan
Period
Teaching and Collecting data
1
Pre-test (conceptual test)
50 minutes
Review of kinematics
15-20 minutes
ILD teaching in Newton’s first law:
2
Demonstration 1 - 3
ILD teaching in Newton’s second law:
Demonstration 4 - 6
ILD teaching in Newton’s second law:
3
Demonstration 7 - 8
ILD teaching in Newton’s third law:
Demonstration 9 - 10
4
Time duration
Post-test (conceptual test)
40 minutes
40 minutes
50 minutes
50 minutes
50 minutes
5.6 Data analysis
The data will be collected and analyzed for quantitative results from the pre- and posttests as well as the prediction sheets. For qualitative results, the observation from video
camera will be used.
6. Expected results
From the research study, the results that we expect are
- the prior knowledge of Thai high-school students in Newton’s laws of motion and
- the demonstration sets that can be used to enhance students’ understanding in
Newton’s laws, especially the electromagnetic demonstration sets that can be used to
help student’s understanding in non-uniform forces.
15
7. Research Time Table
2007
2008
2009
Activities
8
9
10 11 12 1
2
3
4
5
6
7
8
9
10 11 12 1
2
Review papers
Design tools
Trial tools
Improve tools
Teaching with
sample groups
Thesis proposal
Analyzing data
Thesis writing
Thesis defense
References
[1] Sokoloff, D. R., & Thornton, R. K. (1997). Using interactive lecture demonstrations to
create an active learning environment. The Physics Teacher, 35, 340–347.
[2] Thornton, R. K., & Sokoloff, D. R. (1998). Assessing student learning of Newton’s
laws: The Force and Motion Conceptual Evaluation and the Evaluation of Active
Learning Laboratory and Lecture Curricula. American Journal of Physics, 66, 338–
352.
[3] Hake, R. R. (1998). Interactive-engagement versus traditional methods: A sixthousandstudent survey of mechanics test data for introductory physics courses.
American Journal of Physics, 66, 64–74.
[4] McDermott, L.C.,& Redish, E.F. (1999). Resource letter:PER-1:Physic education
research. American Journal of Physics, 67(9), 755-767.
3
4
16
[5] Halloun, I. A., & Hestenes, D. (1987). Modeling instruction in mechanics. American
Journal of Physics, 55, 455–462.
[6] Halloun, I. A., & Hestenes, D. (1985) Common sense concepts about motion.
American Journal of Physics, 53, 1056–1065.
[7] Halloun, I. A., & Hestenes, D. (1985). The initial knowledge state of college physics
students. American Journal of Physics, 53, 1043–1055.
[8] Young, H. D., Freedman, R. A. (2008). University Physics: Newton’s laws. Pearson:
Addison Wesley.
[9] Hewitt, P.G. (2006). Conceptual physics. Pearson: Addison Wesley.
[10] Thornton, R. K. (1995). Conceptual dynamics: Changing student views of force and
motion. In C. Tarsitani, C. Bernardini, & M. Vincentini, editors, Thinking Physics for
Teaching. Plenum Publishing.
[11] Bao, L., Hogg, H., & Zollman, D. (2002). Model analysis of fine structures of student
models: An example with Newton’s third law. American Journal of Physics, 70, 766–
788.
[12] Wandersee, J. H., Mintzes, J. J., & Novak., J.D. (1994). Research alternative
conceptions in science. In Handbook of Research of Science Teaching Learning
(pp.177–210). Macmillan Publishing: New York.
[13] Jairuk, U. (2007). The use of Interactive Lecture Demonstrations in force and motion
to teach high school-level physics. M.Sc.thesis, Mahidol University, Thailand.
[14] Tanahoung, C. (2008). Developing students’ conceptions of Heat and Temperature
using the Interactive Lecture Demonstrations. Ph.D.thesis, Mahidol University,
Thailand.
[15] Dart, S. L. (1985). Energy laboratory. American Journal of Physics, 53, 320–322.(14)
[16] Kraftmakher, Y. (2008). Maglev for students. European Journal of Physics, 29, 663–
669.
[17] Bednarek, S. (1992). Magnetic track for experiments in mechanics. American Journal
of Physics, 60, 664–666.
[18] Aguilar, H. M. (2007). Magnetic Levitation and Newton’ Third law. The Physics
Teacher, 45, 278-279.
[19] Emarat, N., Arayathanitkul, K., Soankwan, C., Chitaree, R., & Johnston, I. (2002).
The effectiveness of the Thai traditional teaching in the introductory physics course: A
comparison with the US and Australian approaches. CALLab5.
17