lookang
«
Embed this message
Reply #1 on: July 03, 2008, 04:39:03 pm » posted from:Singapore,,Singapore
working on this
Logged
lookang
«
Embed this message
Reply #3 on: July 15, 2008, 06:43:55 pm » posted from:Mountain View,California,United States
Designed by Fu-Kwun Hwang
http://www.phy.ntnu.edu.tw/ntnujava/ Original Source code by Fu-Kwun Hwang
http://www.phy.ntnu.edu.tw/ntnujava/index.php?topic=186.0 Derived work by Wee Loo Kang under creative commons
http://creativecommons.org/licenses/by/2.5/tw/deed.en Kinematics is the science of describing the motion of objects using words, diagrams, numbers, graphs, and equations. The goal of any study of kinematics is to develop sophisticated mental models which serve to describe (and ultimately, explain) the motion of real-world objects. This applet has a real world side view on an object (grey circle) at the top with physical quantities like Displacement, Velocity and Acceleration. (color coded for ease of association). The middle has 3 graphs each showing real time relationship from left to right, they are:
1. Motion with Displacement vs. Time Graph
hints:
Meaning of Shape of D-t Graph
Meaning of Slope of D-t Graph
2. Motion with Velocity vs. Time Graph
hints:
Meaning of Shape of v-t Graph
Meaning of Slope of v-t Graph
Meaning of Area on a v-t Graph
3. Motion with Acceleration vs. Time Graph
hints:
Meaning of Shape of a-t Graph
Meaning of Area on a a-t Graph
Notice that there are scaffolds text to describe the motion instantaneously for learning of physics of motion, to heighten the support to learners to understand the relational meaning of the 3 graphs.
All the graphs are dynamically calculated using equations of motion dx/dt = v and dv/dt = a. (refer to the Model - Evolution Page & Custom Function getV for the details of implementation of the moving points on the v-t graph) It also has a dropdown menu bar for common motions to support ease of exploration and sense making of words to the motion it describes for high school or secondary school learners.
at_rest;
uniform_motion_=_10;
uniform_motion_=_20;
uniform_motion_=_-10;
uniform_motion_=_-20;
simple_acceleration;
simple_deceleration;
negative_acceleration;
positive_deceleration;
edit_v-t_graph"
The slow checkbox allows for slowing down the simulation for higher velocities examples.
What is
http://creativecommons.org/licenses/by/2.5/tw/deed.en You are free:
to Share — to copy, distribute and transmit the work
to Remix — to adapt the work
Under the following conditions:
Attribution. You must attribute the work in the manner specified by the author or licensor (but not in any way that suggests that they endorse you or your use of the work).
Attribute this work:
What does "Attribute this work" mean?
The page you came from contained embedded licensing metadata, including how the creator wishes to be attributed for re-use. You can use the HTML here to cite the work. Doing so will also include metadata on your page so that others can find the original work as well.
For any reuse or distribution, you must make clear to others the license terms of this work. The best way to do this is with a link to this web page.
Any of the above conditions can be waived if you get permission from the copyright holder.
Nothing in this license impairs or restricts the author's moral rights.
Previously
A script on the page "Illustrate increasing/decreasing displacement at increasing/decreasing rates." (
http://www.phy.ntnu.edu.tw/ntnujava/index.php?PHPSESSID=92b971004d55f1f0a04d1efc0a9f2d17&topic=710.msg2589#new ) is making Safari unresponsive. Do you want to continue running the script, or stop it?
what is wrong?
Mac OSX cannot load failed
Windows XP can load properly
strange? any thoughts?
need time to figure out why
source code download the *.jar for using the applet on standalone without internet connection.
*** There are 1 more attached files. You need to login to acces it!
« Last Edit: August 21, 2009, 10:31:13 am by lookang »
Logged
Fu-Kwun Hwang
«
Embed this message
Reply #4 on: July 15, 2008, 09:29:49 pm »
I was not able to view the applet you have posted (the first message). May be that is the reason why the Safari did not response.
There might be other reason to cause browser unresponsive. e.g.
If I viewed java applet with Firefox 2 with JDK 1.6.0_06 , the browser will hangup (when java embed in the html).
You can find out similar report at
http://forum.java.sun.com/thread.jspa?messageID=10221200 Now, I switch to Foreox 3 and install latest JDK1.6.0_07 and it work just fine when I view other topic.
May be you can try to update to latest java run time.
Logged
Fu-Kwun Hwang
«
Embed this message
Reply #5 on: July 20, 2008, 05:43:18 pm »
I installed Safari on my computer and the above simulation was working fine.
This post is created when I was using Safari. The interface look nice!
:-)
Logged
lookang
«
Embed this message
Reply #6 on: July 21, 2008, 09:11:28 pm »
i think i will revert to a lower version of EJS and recompile the applet.
made some changes
Logged
lookang
«
Embed this message
Reply #7 on: September 08, 2008, 01:20:08 pm » posted from:Singapore,,Singapore
any idea why the new applet at the very top cannot load ?
i recompile the output.
uploaded to a separate folder
rename the codebase to "http://home.phy.ntnu.edu.tw/~lookang/EJS/ejs_group.files/weexvav12.app/"
code="weexvav12.weexvav12Applet.class"codebase="http://home.phy.ntnu.edu.tw/~lookang/EJS/ejs_group.files/weexvav12.app/"archive="common.jar,weexvav12.jar,"name="weexvav12"id="weexvav12"width="800"height="489"
Logged
Fu-Kwun Hwang
«
Embed this message
Reply #8 on: September 08, 2008, 03:53:52 pm » posted from:Taipei,T'ai-pei,Taiwan
I can view the applet in the first message body very well.
It run nicely. So I do not know what is the problem.
If you are using Firefox, Please check out "error console" and let me know what was shown their.
Logged
lookang
«
Embed this message
Reply #9 on: September 09, 2008, 02:29:33 pm » posted from:SINGAPORE,SINGAPORE,SINGAPORE
i see what you mean now, it load very slowly, i waiting for 5 minutes or so before the applet comes alive!
thanks! there is no problem now
Logged
Fu-Kwun Hwang
«
Embed this message
Reply #10 on: September 09, 2008, 02:35:18 pm » posted from:Taipei,T'ai-pei,Taiwan
May be you did not have enough RAM or there are too many processes running at the same time.
I did not find any delay with my browser/computer.
Java need a lot of RAM if the program is for many dynamic objects.
Logged
lookang
«
Embed this message
Reply #11 on: September 10, 2008, 10:26:06 pm » posted from:Mountain View,California,United States
LOL... you are right, it worked on windows 2 Gig ram (home), beautifully.
the other machine has windows 1 GB ram is slow until like not working when loading this page.
the joke is it was 512 Mb, until i added another 512 Mb thanks to a "friend".
i learn alot from you....thanks!
« Last Edit: September 11, 2008, 10:04:06 am by lookang »
Logged
Fu-Kwun Hwang
«
Embed this message
Reply #12 on: September 10, 2008, 10:48:24 pm »
RAM is relative cheaper. I would suggest you upgrad your RAM. Otherwise, you will waste a lot of time due to that.
I would rather has less powerful CPU but I want to have more RAM.
A high power CPU with less RAM is similar to a high speed car with small gas tank.
If you need to add gas every 3km, there is no need to have a high powered engine. :-)
Logged
lookang
«
Embed this message
Reply #13 on: September 11, 2008, 09:44:20 am » posted from:SINGAPORE,SINGAPORE,SINGAPORE
my home computer windows OS is P4 3.0 GHZ with 2 GB ram, which i upgraded another 1 GB ram recently
my 8 am to 6 pm computer is also windows OS is P4 3.0 GHZ with 1 GB ram, which i can't increase the ram by myself:(
i will remember to share that joke around LOL "If you need to add gas every 3km, there is no need to have a high powered engine. :-)"
Logged
lookang
«
Embed this message
Reply #14 on: September 11, 2008, 08:24:26 pm »
strange,MAC OSX seems to have problem loading using both firefox 3 and safari. Any thoughts ? could it be the Java version of 1.5 instead of 1.6 needed ?
Java Plug-in 1.5.0
Using JRE version 1.5.0_13 Java HotSpot(TM) Client VM
User home directory = /Users/11
----------------------------------------------------
c: clear console window
f: finalize objects on finalization queue
g: garbage collect
h: display this help message
l: dump classloader list
m: print memory usage
o: trigger logging
p: reload proxy configuration
q: hide console
r: reload policy configuration
s: dump system and deployment properties
t: dump thread list
v: dump thread stack
x: clear classloader cache
0-5: set trace level to
----------------------------------------------------
« Last Edit: September 11, 2008, 08:27:34 pm by lookang »
Logged
Fu-Kwun Hwang
«
Embed this message
Reply #15 on: September 11, 2008, 08:36:47 pm »
I do not have a Mac machine so I can not tell.
However, I always update to latest version.
I am using 1.6.0_07-b06
I download the above version because I wanted to try chrome (Google new browser).
It need latest java run time to view java applet.
Logged
lookang
«
Embed this message
Reply #16 on: September 11, 2008, 08:49:36 pm »
unfortunately under software, updates the curent java is the latest version.
guess i will find out why in later time
the earlier java applets like the vernier works in MAC OSX.
think i remember a check box to select java 1.5 or 1.6 compatible in EJS 4.0..... i go take a look again
« Last Edit: September 11, 2008, 09:02:16 pm by lookang »
Logged
Fu-Kwun Hwang
«
Embed this message
Reply #17 on: September 12, 2008, 09:06:32 am » posted from:Taipei,T'ai-pei,Taiwan
You can select different JRE in EJS if you have more than one version installed.
In the past, it only affect EJS. EJS will use selected JRE to run itself and generated simulation.
However, java process did not kill itself when EJS or any java application finished, now.
The java console is always there once java has been activated.
I am not sure how it will affect your browser in MAC.
But I can select which JRE to use be used from java control panel (Right click java console icon) in Window system.
Logged
Fu-Kwun Hwang
«
Embed this message
Reply #19 on: September 18, 2008, 11:28:54 am » posted from:Taipei,T'ai-pei,Taiwan
The above simulation works fine with my browser. Simulation at the above link is also working fine.
So I do not know what is the problem? Is it due to your browser setting?
Logged
lookang
«
Embed this message
Reply #20 on: September 18, 2008, 12:21:17 pm » posted from:SINGAPORE,SINGAPORE,SINGAPORE
i suspect firefox 3 on Mac osx is giving me this problem.
i tried safari on Mac osx nope it also didn't load as well
Yes, you are correct, the above applet does load properly even with Windows 1gb ram, take some time but work well:)
Question:how to make the simulation more like fall and rebounce ?
i have this technical problem,
to make T[4] = 10 and T[6] = 10.
but it will screw up the rest of the calculation for acceleration etc....
any simple way to make the simulation more like a fall and rebounce on a hard surface ?
but i don't want to affect the original codes for the rest of the options.
any tips?
tricky right?
« Last Edit: September 18, 2008, 10:39:31 pm by lookang »
Logged
Fu-Kwun Hwang
«
Embed this message
Reply #21 on: September 18, 2008, 03:54:46 pm » posted from:Taipei,T'ai-pei,Taiwan
Is it two questions? or one question?
Question:how to make the simulation more like fall and rebounce ?
The particle was moving in the horizontal direction. I do not feel any
fall effect?
May be you can draw another particle moving vertically (but you call it x , it will make user confused).
How about draw both vertical and horizontal at the same time.
and
i have this technical problem, to make T[4] = 10 and T[6] = 10. but it will screw up the rest of the calculation for acceleration etc.... any simple way to make the simulation more like a fall and rebounce on a hard surface ? but i don't want to affect the original codes for the rest of the options.
I do not understand your question? What is T? Why it will affect acceleration.
Could you copy the code and let me know where is the code? (constrains/user defined functions,...)
Logged
lookang
«
Embed this message
Reply #22 on: September 22, 2008, 09:57:57 am » posted from:Singapore,,Singapore
nevermind, i give up on the up and down, it is only a left and right applet now..
i will be adding capability for aiding this learning process.
Activity: Predict the Motions
Aim: In this activity, students explore the relationships between position and velocity of a moving object with the help of the datalogger. Students will use the distance sensor to track an object’s motion and to correlate the actual motion with its associated position-time, velocity-time and acceleration-time graphs in real time. Students will learn that from the graphical representations, it is possible to determine in what direction an object is moving, how fast it is moving, how far it travelled, and whether it is speeding up or slowing down.
Focussing Question(s):
• How do the position-time, velocity-time and acceleration-time graphs relate to the actual motion of an object?
• What do the gradients of the position-time and velocity-time graphs tell us about the motion?
• What does the area under a velocity-time graph represent?
Initial Activity:
• As a pre-lab activity, students are asked to sketch the position-time and velocity-time graphs of an object for different situations of an object:
o at rest;
o moving in the positive direction with a constant speed v;
o moving in the positive direction with a constant speed 2v;
o moving in the negative direction with a constant speed v (i.e. velocity = -v).
Logged
lookang
«
Embed this message
Reply #23 on: November 06, 2008, 09:59:30 am » posted from:Singapore,,Singapore
thanks to your help, i have converted to sharing jar files directly as a download available in your forum.
my html version of EJS applets seems to work and not work on some computers (Win or Mac).
every post of mine in community board has the option to download the jar files now!
the xml source code is also included in the jar package! so cool and easy.
wonder if iphone can run jar files? hhmmmmm
Logged
lookang
«
Embed this message
Reply #25 on: September 02, 2009, 09:19:50 am » posted from:Singapore,,Singapore
changes made:
1. added <> steps
2. added trail of object of visualizing, courtesy of Prof hwang's code
http://www.phy.ntnu.edu.tw/ntnujava/index.php?topic=716.0 3. added the coordinates ( T[jid,yv[jid] ) to be shown when mouse over for clarity of exploring data points
4. made the checkboxes remember previous selection for ease of inquiry learning
5. added more boolean checkboxes for visualization of quantities
now and before a recent scanning of good applets
source codes in zip in attached here cos i can't attach at the top post without messing up the picture preview
*** There are 1 more attached files. You need to login to acces it!
« Last Edit: September 02, 2009, 09:23:35 am by lookang »
Logged