Download PhET Colorado: Explanations and Examples

Andrew Krejci
Instructional Applications of the Internet
Web Application Overview of Physics Simulations
Dr. Drew Tiene, Fall 2015 11/3/14
Computer simulations can teach physics as students discover relationships through a
model that reacts to a changing variable. Good simulations incorporate a student’s senses and
decision making in an easy to use and flexible interface. Two high school classroom physics
simulations, PhET Online Simulations and Interactive Physics software, are overviewed. The
guided discovery of PhET simulations allows students to study a specific phenomenon as
opposed to the open ended construction and data acquisition of Interactive Physics. Simulations
can be aligned to state standards and promote the goals of the Science, Technology, Engineering
and Mathematics Education Coalition or STEM. Simulations can be used in the classroom as
interactive demonstrations, exploration exercises, virtual labs and closure activities. Technical
boundaries, classroom management and mastering the software all present challenges in the
classroom when using computer simulations in a physics classroom.
Purpose and General Features:
A computer simulation can teach physics by having students observe, discover and
explore a computer model. Students learn by manipulating variables in a physics simulation and
receiving immediate feedback. Science and engineering are built on models and physics
simulations provide models of real life experiences that are sometimes unattainable for a student
in a classroom. Simulations provide an environment students can explore like scientists without
the lab supplies or set up time.
Simulations produce data for students to analyze and interpret. While running a
simulation, students see and record real time data as pictures, graphs, tables, motion diagrams,
etc. Students use this perfect data to make basic calculations, such as force, acceleration and
momentum, and to discover the cause and effect relationships for themselves through discovery
learning.
Simulations are visual in nature and must appeal to the student’s senses and keep their
attention. When a simulation has a narrative or a specific experiment to conduct, the style and
content need to be appealing and eye catching. The lab equipment, like pumps and pianos, are
faithfully represented and explored. Open world simulations, where users create shapes and
apply any characteristics they want to them, tend to be visually stark and without sound.
A good simulation is easy to use and flexible in different educational settings. A
simulation must encourage exploration by providing immediate feedback when changing a
variable with slider bars or entering a number directly and allow the data to be displayed in any
format the user wants. Open world simulations have a steeper learning curve given the interface
is just an open canvas and some drop down menus. These simulators require tutorials to explore
all the options that are available. The best simulations provide flexibility to different educational
settings and may be available online or to download. With different modes, a simulation may be
used as a demonstration or for data taking or finally to complete complex, enrichment
challenges.
Lessons can be written using simulations to teach required state or national curriculum.
Some simulations offer premade handouts and experiments aligned with the current standards.
Some simulations have texts and workbooks available for purchase while other simulations post
users’ lesson plans as worksheets or power points to share with everyone. An online course can
use simulations for demonstrations and labs creating a completely virtual classroom.
Simulations teach best with project based inquiry lessons. By first exploring, students
learn the basics of a concept. With this knowledge and some scientific inquiry, the student then
can explore the simulation to discover new aspects of the system not readily observable. With
this deeper understanding, the students can be assigned an open ended task to complete by
testing multiple hypotheses and engaging in higher order learning. A lesson’s educational value
still depends on the teacher’s inspiration and creativity.
Examples and Comparisons:
Simulations can model simple laws of motion of a school’s curriculum or millions of
particles bouncing down steps used for research in crowd control. A few of more complex
simulators include Blender, Powdertoy and Physion. Being a high school physics teacher, I will
concentrate on two classroom simulations, PhET Simulations available online from the
University of Colorado and Interactive Physics, a program my school purchased from Design
Simulation Technologies for the physics department.
PhET Interactive Simulations is an educational, nonprofit venture dedicated to providing
a free and open exploratory environment for anyone in the world to engage in content like a
scientist. Originally founded by Dr. Carl Weiman with his Noble prize money, the website has a
collection of over 100 simulations in physics, chemistry, earth science, biology and math. PhET
simulations are created with education based research driving the design. (Univ. of Colorado,
2013)
Interactive Physics is an open ended physics simulator (Design, 2014) in which the user
creates objects, defines their parameters and conducts experiments. A student can just explore or
can be given a task to complete like shooting a ball through a hoop. The students build and
manipulate the models, run the simulation, interpret the data, make more adjustments and repeat.
PhET simulations collect the data specific for the specific simulation while Interactive
Physics permits the student to collect any data needed. Both simulations produce perfect data so
that students do not miss out on relationships between variables due to outside errors like
friction. Both simulations display real time data in table, graphs, and motion diagrams.
Students are guided through the PhET simulations while the students using Interactive Physics
need an idea of what they want to build before they start to start a simulation.
The simulations from PhET are more visually stimulating than those of Interactive
Physics. PhET simulations are designed to be colorful and eye-catching by testing them on
students while in development. PhET simulations are as simple as possible and include everyday
objects, sometimes with some humor thrown in, like a bulldog on a skateboard, a Buick as a
projectile or John Travolta getting shocked by a doorknob. The simulations provide implicit
guidance with just enough controls to send the user in a direction so that the student leans
forward and not just sits back watching a screen. Interactive Physics starts with a white screen
on which you draw shapes and watch them move. Colors and textures may be added but
everything is still made of primary shapes and come out in one color. PhET simulations look
like real life while Interactive Physics looks like building blocks.
PhET simulations create a scenario and guide a student through the discovery process.
Each simulation has a handful of parameters to vary and make observations. Maximum and
minimum values are easily discovered and abstract variables such as electric field strength can be
visually represented. PhET also includes different levels of complexity so basic and enrichment
exercises can occur in one simulation. The open-endedness of Interactive Physics, while freer to
manipulate, makes it difficult to start with something substantial. Dozens of menu options are
best learned with tutorials and demos. Once proficient, the student can build whatever the
imagination can provide. Interactive Physics does not include levels of complexity in its
simulations.
PhET allows teachers to share lessons using the simulations. Free to download, dozens
of lessons suitable for all ages can be followed directly or used as inspiration. The Ohio
Department of Education suggests specific PhET Simulations as instructional strategies and
resources in its physics curriculum. (Ohio, 2014) Interactive Physics sells texts, workbooks and
premade labs for both high school and college support with supplemental exercises and activities
for easy lesson planning and grading.
Instruction and Learning:
Simulations present a risk-free environment where students are free to make mistakes and
try again without wasting materials or breaking lab equipment. Active learning occurs as
students have an experience that cannot normally be found in a classroom. Students can
visualize and learn abstract concepts with multiple real time translations of data. Simulations
support STEM, Science, Technology, Engineering and Math curriculum by providing engaging
drills until levels of mastery are reached and also encourage collaboration between students
In the classroom, simulations facilitate learning by actively engaging a student’s senses
while exploring and experimenting. At the very least, simulations could be used as interactive
demonstrations with lectures but work best in the hands of the students. Before even taking a
note on a new topic, set the students down in a simulation to explore and familiarize themselves
with the parts of the system and their relationships. Once the student recognizes the relationship,
data is take to solidify the relationship with a formula. The equation for acceleration,
acceleration=force/mass, can be deduced through a simulation. Simulations can be used as
virtual pre-labs of physical, hands on labs. (Gende, 2011) I have found students can make a
basic circuit faster if they encounter a virtual circuit board first. Simulations are better than
standard hands on labs when students can change variables not normally can be changed, like the
mass of a cart or the charge on a balloon. Especially with the open style of Interactive Physics,
simulations encourage project based learning, perhaps using unattainable materials and novel
conditions. If patient enough, complex systems can be built. Simulations can be used as solely
games with the student truly experimenting with variables and cause and effect relationships to
win. When students play a lunar lander or electric field hockey, they experience and familiarize
themselves with all the complexities in a system. A simulation can be used as a closure activity
or exit slip. Giving the students an specific answer, they must determine initial conditions before
packing up or leaving.
Simulations do not encourage communication and information dissemination but research
is. The only sharing going on are lessons posted at the PhET website CITATION but no dialog,
wiki or blog. The students conduct their own research in a classroom simulation. The more
advanced simulations are used throughout science, engineering and math research.
I have placed a couple sample lessons I made using PhET simulations as examples.
PhET Energy Skatepark page where dozens of lessons are shared.
http://phet.colorado.edu/en/simulation/energy-skate-park
Challenges and Issues:
Since simulations require computer access, district technology and classroom
management are always an issue. To a modern student, a slow computer is worse than no
computer or one that won’t give permission to run an application. Even with two students to a
computer, one person is still sitting there watching. The guided simulations usually represent
only one concept so some students tire quickly of the screen. Keeping students on task and
turning your back to the class when facing a computer screen requires classroom management to
keep students on task. Instructional time is always lost when moving students to and from the
computer stations or a computer lab as well as getting every computer at the same spot in the
simulation.
Learning software well enough to create great lessons also challenges the implementation
of physics simulations. The teacher has to learn the software well enough to teach with the
software. As with all computer programs, if the teacher commits to using the software,
eventually the teacher will learn it. I am still in the bend of Interactive Physics’ learning curve.
Cookbook labs are easy to write but a problem based lab take time. Great lessons come from
creating the big question for the lesson which takes time and inspiration.
Included are some links videos about PhET Simulations and Interactive Physics:
Wiimote Whiteboard Travoltage http://phet.colorado.edu/
http://www.youtube.com/watch?v=MEiLaL0O9Mg
2006 Physics Award Winner: PhET - Physics Education Technology at the Univ. of Colorado
http://www.youtube.com/watch?v=MByoCrtPMJM
PhET Colorado: Explanations and Examples
http://www.youtube.com/watch?v=hMfUTDGYvyU
How to build a simple trebuchet in Interactive Physics
http://www.youtube.com/watch?v=cp1kjPh_jXA
Students explore physics simulations to discover on their own scientific principles. A
good simulation should draw in a student and till be easy to use and flexible for all levels of
learners and curriculums. Depending on the lesson, a guided simulation, like PhET, can help
students learn a concept or if on screen creativity and increased data acquisition are needed, open
world simulators, like Interactive Physics, can help a student to learn physics.
Design Simulations Technology. (2014) Interactive Physics. Retrieved from
https://www.design-simulation.com/ip/index.php
Gende, D. (2011, April 1). Science Simulations: A Virtual Learning Environment. Retrieved
from http://plpnetwork.com/2011/04/01/science-simulations-a-real-way-to-learn/
Ohio Department of Education. (2014) Science Standards, pg. 201. Retrieved from
http://education.ohio.gov/getattachment/Topics/Ohio-s-New-LearningStandards/Science/Science_Standards.pdf.aspx
University of Colorado. (2013). PhET Interactive Simulations. Retrieved from
http://phet.colorado.edu/
PhET Energy Skate Park Lab
Name:
Per: Date:
Google “PhET simulations” and click on the first result. Click PHYSICS, click WORK, ENERGY and
POWER, click on ENERGY SKATE PARK: BASICS. RUN and let Java load.
Fill in the Kinetic,
Potential, Thermal
and Total Energies
when the
skateboarder is at
the position.
How does the total
mechanical energy
change with time?
Fill in the Kinetic,
Potential, Thermal
and Total Energies
when the
skateboarder is at the
position.
How does the total
mechanical energy
change with time?
Fill in the Kinetic,
Potential, Thermal
and Total Energies
when the
skateboarder is at the
position.
How does the total
mechanical energy
change with time?
Click on the Friction Tab. Turn Friction ON and LOTS.
Fill in the Kinetic,
Potential, Thermal
and Total Energies
when the
skateboarder is at
the position.
How does the total
mechanical energy
change with time?
Fill in the Kinetic,
Potential, Thermal and
Total Energies when
the skateboarder is at
the position.
How does the total
mechanical energy
change with time?
Fill in the Kinetic,
Potential, Thermal and
Total Energies when
the skateboarder is at
the position.
How does the total
mechanical energy
change with time?
Click on INTRODUCTION TAB, the second QUARTER PIPE and turn on the GRID.
Assume the skater’s mass is 60 kg. Determine his speed at the
bottom of the ramp.
V= _______________________________
Make a successful loop. Draw it in and determine the skater’s
velocity when inverted.
V= _______________________________
Close ENERGY SKATE PARK: BASICS and open the regular ENERGY SKATE PARK. Run the half
pipe simulation.
Drop the skater into the half pipe and explore all the
different options with and without friction. Pay special
attention to the Energy vs. Position graph and Energy vs.
Time graph.
Please entertain yourselves for the rest of the period by
exploring and changing all the different variables.
**Explain what this entire exercise helped you understand better.**
P PhET Electric Field Hockey Lab
Name:
Per: Date:
_______________________________ of charge- The electric field caused by a collection of charges is
equal to the ___________________ of the electric fields caused by the individual charges).
Play hockey with electric charges.
Place charges on the ice, then hit start to try to get the puck in the goal.
View the electric field. Trace the puck's motion.
What do the blue arrows represent? _________________________
1. Predict where to place a positive charge to move the positive puck
into the goal.
Draw in its electric field.
Draw in a Electrostatic Force Vector on the positive puck
Draw in the particle’s predicted path.
Test out your prediction.
2. Predict where to place a negative charge to move the positive
puck into the goal
Draw in its electric field.
Draw in a Electrostatic Force Vector on the positive puck
Draw in the particle’s predicted path.
Test out your prediction.
3. Predict where to place any number of any sign charges to move
the positive puck into the goal.
Draw in the electric field.
Draw in an Electrostatic Force Vector on the positive puck at
various key points of the plan.
Draw in the particle’s predicted path.
Test out your prediction. Keep trying unit successful.
Show the final plan.
Goal!
How close are your prediction and the actual layout?
Why are they different?
4. What do you think increasing the mass of the puck affects speed?
What do you think increasing the mass of the puck affects total time?
What do you think increasing the mass of the puck affects the traced path?
5. Draw out your final solutions above to Difficulty Levels 2 and 3.
Before the
end of the period, show Mr. Krejci these two questions.
1. The positive puck to the right  made it into
the goal. Using the electric field, predict the path
of the puck.
2. Predict the direction the
positive puck in the center
of the four charges would
move and draw an arrow
from the puck.
PhET Circuit Construction Kit (DC Only) Lab
Name:
Per:
CURRENT, I
Add some wires.
Add a battery.
Right click to show or change the voltage
Check AMMETER to measure electric current and place it in the circuit
Add more wires
Finally, connect the wires to form a circuit.
What happens?
S____________C______________________- an electric circuit that
allows the current to travel with very little or zero resistance.
- may cause sparks and exploding batteries
For our precision, wires and batteries have 0 Ω resistance.
What was the ammeter reading?
Notice the reduced animation speed.
RESISTANCE, R:
Add a resistor and right click to SHOW VALUES.
Resistors transform electrical potential energy to heat through friction.
Read the ammeter. Notice the resistor slows down the flow of electrons.
Using V, I and R, figure out Ohm’s Law
Ohm’s Law:
V= ________________
R = _________________
I = ________________
Change the voltage and the resistance to calculate a new value for current.
V= ________________
R= _________________
I = ________________
Reminder, Voltage is a measure of how much energy per charge at a point.
(Joule/Coulomb= Volt)
Date:
Predict what happens to the current if the voltage is increased. (INCREASE/DECREASE)
Increase the voltage by sliding the control and watch how the electrons react.
Verify that as the voltage increases, the current (INCREASE/DECREASE). Voltage and
current have a (DIRECT/INDIRECT) relationship.
Predict what happens to the current if the resistance is increased. (INCREASE/DECREASE)
Increase the resistance by sliding the control and watch how the electrons react.
Verify that as the resistance increases, the current (INCREASE/DECREASE). Resistance
and current have a (DIRECT/INDIRECT) relationship.
Test and check your lab partner. Uncheck SHOW VALUE on one component and change
the values on the other two. Challenge your lab partner to calculate the unknown value.
V= ________________
R = ________________
I = _________________
Using the GRAB BAG, find the resistance of one object.You may need to check MORE VOLTS on the battery.
Object: _________________
V= ____________ I = _____________ R = ________________
VOLTAGE
RESET ALL to clear the screen, add a battery and check VOLTMETER.
Use the leads of the voltmeter to determine the voltage of the battery.
Set up a simple circuit with a battery, wires, ammeter and a light bulb.
Explore the circuit with the two voltmeter leads keeping in mind you are reading the
difference in voltage between two points.
Check the change in voltage along a single wire and calculate the resistance _____Ω
CALCULATE ENERGY OF LIGHT BULB EVERY SECOND
Current equals charge per second and voltage equals energy per charge, Determine
how much energy was given off by the light bulb as heat and light every second.
First, determine the amount of charge flowing through the light bulb every second.
I=Q/t
Using the voltage drop across the light bulb, determine the amount of heat and light energies given off by the
bulb. V= PE/Q = Energy/Charge
ENERGY = ______________ Joules every second
Predict the brightness of the light bulb if the voltage, meaning energy per charge, is increased. Verify.