Notes
on simulations developed by John Clement.
John is a
long-time physics modeler in Houston. John earned a Ph.D. and has extensive
career experience in the private sector. He is an avid reader of physics
education research, and he has done considerable action research in his
classroom, and given presentations on it at AAPT meetings and conventions of
other professional societies.
– Jane Jackson
Date: Sat, 17 Sep 2016
From: John Clement
<clement@HAL-PC.ORG>
Subject:
Simulations
Due to changes
in my ISP, I had to move my simulations and simulation links to:
http://Jclement.altervista.org
The direct link
is http://jclement.altervista.org/Simulations/science.htm
I had to revise
a number of them to make them work on the new host. So it is possible that your favorite may not work. Please let me know which ones are
broken or missing.
These are
modeling-friendly in that they do not give the theory, and are suitable for
exploration and paradigm labs.
Some physical labs take a long time, but since these simulate physical
labs, you can cut the time for the lab work. It is recommended that you show then a physical setup of the
same situation during the initial concrete preparation brainstorm.
There is some
evidence that simulations may work marginally better. For example they found that students using circuit
simulations could wire up a circuit faster than students who did equivalent
activities with physical equipment.
Date: Fri, 30 Sep 2016
The simulations
at
http://jclement.altervista.org_Simulations_science.htm
Should now all
be operational except for some which are not under my control. Some links to outside simulations are
not correct. The simulation of
mixing colored light was kindly supplied by another person and needs to be
changed to be in line with current Java standards. It can be run if added to the Java exception list.
I have tested
them on both Firefox and Internet Explorer. Some of them do not work well when first started. You may have to click reset or run,
then reset. It is my impression
they are buggier under Firefox, but they work with IE. They have also been tested on a Mac and
seem to run OK there.
The MOP
simulations may be missing pictures on some computers or browsers. They work OK with IE under Windows 7
and 10. This is a problem that has
not been solved yet!
My original ISP
stopped supporting user web sites and wiped them all out. The rest of my original web page
is a bit of a mess, but pieces of it have been moved elsewhere. The new web site does not properly
handle either spaces or underscores in the names, so I had to make wholesale
changes. It is possible that some
of my simulations have not been properly renamed, so please let me know if any
particular favorite can not be accessed.
Date: Sat, 8 Oct 2016
From: John Clement
<clement@HAL-PC.ORG>
Subject: Java
Simulations
While I have put
JAVA simulations on the web, everyone should be aware that
they may have
problems, depending on the web browser.
JAVA is undergoing a
severe makeover
and the usual way of creating applets is going away. Rather
than fixing the
security, the developers are essentially trashing useful
tools. The developers of Physlets are busy
changing the code so it will
work with the
current standards, but the browsers may implement changes
before the new
code is complete. Currently
Internet Explorer seems to work
best, and
Firefox is usable on Macs. But
Firefox is spotty on Windows and
Chrome is
reputed to not work at all. Edge
reputedly doesn't support Java.
I will attempt to go with the flow and
fix things as problems are found, but
I can't always
beat the game. I have fixed some
links and have modified
some of my
simulations to be more friendly to older standard definition
displays. In particular, the cart on ramp
simulations should work better
with older
displays that are not wide screen.
However, a scrolling
problem is
present in all Java. If you
scroll, the Java pictures are
messed up. Most of my simulations do not need
scrolling for 1080 vertical
displays. The workaround is to refresh the
browser. The sliding controls
usually work
either for full scrolling to the top or bottom. Messed up
graphs/pictures
are restored by reset or start.
Other Physlets by the developers also
have similar problems, so this is not just my problem.
------------------------------
Nov. 10, 2016
I have updated
the gravitational force simulation.
1. It should have all controls visible,
even for a non-widescreen projector/display.
2. It has direct readount of the distance
between the masses, and the force
http://jclement.altervista.org/Simulations/science.htm
The
gravitational simulation is at the bottom of the page.
Finding the
force by measurement is a bit too time-consuming, and now students cannot make
a mistake if the test mass is moved up or down.
The data should
look better. (Also, in the
previous version the only way to figure the force was to measure the length of
the arrow. This causes problems
with students who do not understand negative/positive. When the arrow crosses over zero and
they click on the ends to find the length, they can get a negative and a
positive number. Then then
subtract them incorrectly by not noticing that one of them is negative.)
However, I have
encountered a problem with this simulation on Firefox on a Mac that is set to
non-widescreen mode. The numbers
inside the slider readout boxes are enlarged, which truncates the exponent
readout. Students can click on the
number and then scroll the number, but they may not be aware of this. On my computer, one must click reset to
display the distance and the force initially. However, when the mass is first moved, the data is displayed
even if reset is not used.
This
simulation is quite suitable for modeling the general gravitational force in a
paradigm lab. Since this can not be modeled with a
real physical lab, the simulation lets the students explore how this force
works, both inside and outside the planet. The concrete preparation text explains that one can put the
test mass inside the planet. When
students click run, they think they are seeing it orbit the planet.
Since there is
data that shows simulations work as well as, and sometimes better than,
physical labs, we should not be afraid to use them. They save time which can then be used to tackle other
problems. In particular, some of
the PHET simulations are very good for modeling. The ladybug circular motion simulation is very good, and
also the piston simulation is wonderful for tackling the gas laws. Students do not associate the modeled
gas laws with what they have been told in chem until you write the final
equation in the standard chem form.
Supplementing the ladybug simulation with some simple physical examples
of circular motion is helpful. For
example, kick a bowling ball (or a basketball very gently) to get it to go in a
circle. The bowling ball and broom
or rubber mallet is very good.