Author Topic: Ejs open source kinematics java applet displacement velocity acceleration graphs  (Read 45579 times)

Fu-Kwun Hwang

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Re: Illustrate increasing/decreasing displacement at increasing/decreasing rates.
« Reply #15 on: September 11, 2008, 09:36:47 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.

lookang

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Re: Illustrate increasing/decreasing displacement at increasing/decreasing rates
« Reply #16 on: September 11, 2008, 09:49:36 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, 10:02:16 pm by lookang »

Fu-Kwun Hwang

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Re: Illustrate increasing/decreasing displacement at increasing/decreasing rates.
« Reply #17 on: September 12, 2008, 10:06:32 am »
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.

lookang

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Kinematics of 1 D uniformly accelerated motion
« Reply #18 on: September 17, 2008, 05:41:52 pm »
Question: Is it possible that EJS_4.0_080905 auto generated codes do not work after uploading to a webserver?
it works locally on the computer but after zipping and uploading, it does not. click this to see.
http://home.phy.ntnu.edu.tw/~lookang/EJS/EJS_4.0_080905/weexvav13newaddoption/weexvav13newaddoption.html

added options:
http://home.phy.ntnu.edu.tw/~lookang/EJS/EJS_4.0_080905/weexvav17rebuild/weexvav17rebuild.html





Reference:
http://www.ngsir.netfirms.com/englishhtm/Kinematics.htm


added new options to be able to select
simple acceleration
uniform motion
simple deceleration
rise and fall
fall and rebounce
edit v-t graph


the physics for option "fall and rebounce" is rather too long a time.

any idea how i can improve it ?

source code
download the *.jar for using the applet on standalone without internet connection.
« Last Edit: February 26, 2009, 08:50:27 am by lookang »

Fu-Kwun Hwang

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Re: Kinematics of 1 D uniformly accelerated motion
« Reply #19 on: September 18, 2008, 12:28:54 pm »
Quote
Question: Is it possible that EJS_4.0_080905 auto generated codes do not work after uploading to a webserver?
it works locally on the computer but after zipping and uploading, it does not. click this to see.
http://home.phy.ntnu.edu.tw/~lookang/EJS/EJS_4.0_080905/weexvav13newaddoption/weexvav13newaddoption.html
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?

lookang

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Re: Kinematics of 1 D uniformly accelerated motion
« Reply #20 on: September 18, 2008, 01:21:17 pm »
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?  ;D tricky right?
« Last Edit: September 18, 2008, 11:39:31 pm by lookang »

Fu-Kwun Hwang

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Re: Kinematics of 1 D uniformly accelerated motion
« Reply #21 on: September 18, 2008, 04:54:46 pm »
Is it two questions? or  one question?
Quote
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
Quote
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,...)

lookang

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Re: Kinematics of 1 D uniformly accelerated motion
« Reply #22 on: September 22, 2008, 10:57:57 am »
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).

lookang

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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

lookang

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to discover the laws of kinematics by letting them control the motion of an object.
object can accelerate, slow down or even reverse! aided by real-time graphs.

found this http://www.crescent.edu.sg/crezsphere/applets/Physics/Applets/Kinematics.htm

After Google "kinematics java applet" My applet is top 5 ! Cool


http://qbx6.ltu.edu/s_schneider/physlets/main/constaccel1d.shtml
Likes: the Animation with Ghosted object
   the steps <>

http://www.ngsir.netfirms.com/englishhtm/Kinematics.htm
Likes: Excellent example
« Last Edit: August 23, 2009, 11:14:12 pm by lookang »

lookang

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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
« Last Edit: September 02, 2009, 10:23:35 am by lookang »