Blackbody Radiation

[ahmedelshfie]

Written by Fu-Kwun Hwang
Edited by Loo Kang WEE and Wolfgang Christian
Modified by myself

[ahmedelshfie]

Blackbody Radiation

[ahmedelshfie]

No work too prof 

[ahmedelshfie]

Blackbody Radiation

[Fu-Kwun Hwang]

There is another problem I found:

You did not save the xml file at the standard place.

Normally, you will select a workspace
For example: d:\EJS_4.2.7\workspace or any place like d:\ejsworkspace
There are four subdirectory under the above workspace
config/export/output/source

We should put our xml source under source.

There is a sub-directory under source called users. That is the place for users to save his/her own xml files.
To avoid conflict between users (e.g. two users both create pendulum.xml ), so sub-directory are suggested.

For example: I save all my xml files under
 workspace\users\ntnu\fkh
where ntnu is the university where I did my work. fkh is for myself.
If there is other user at my university, then he/she is suggested to put file under workspace\users\ntnu\xxx where xxx is his/her own identity.

I would suggest you save your xml file under workspace\users\br\ahmed or something else
However, it has to be at least under workspace\users to work.
I believe you save your files at workspace\ahmed , that is the reason why the uploaded jar file did not work. Because it might conflict with others.
Please move you directory ahmed under users (becomes users/ahmed or users/br/ahmed or ...)
and it should work.

[ahmedelshfie]

Hi prof 
I delete ejs and download again and change path
From ejs consol to this D:/EJS_4.2.7/workspace/source/users/br/ahmed\
So after i copy XML file of project and paste in user/br/ahmed
But when i run to open XML file in ejs said "the file selected must be under the source directory"
I don't know what mean it so I'm still now try understand what the problem in path

[ahmedelshfie]

 is not working again

[ahmedelshfie]

I post again now i hope get succeed

[ahmedelshfie]

This is  just test

[ahmedelshfie]

This patm prof after i change i
Will send picture attach i renam user/br/ahmed

[ahmedelshfie]

This is test too 

[lookang]

for me
C:\EasyJavaSimulation\EJS_4.2_091119\EJS_4.2\workspace\source\users\sgeducation\lookang\


you need
br\ahmed\

it will work

[Fu-Kwun Hwang]

Hi prof 
I delete ejs and download again and change path
From ejs consol to this D:/EJS_4.2.7/workspace/source/users/br/ahmed\
So after i copy XML file of project and paste in user/br/ahmed
But when i run to open XML file in ejs said "the file selected must be under the source directory"
I don't know what mean it so I'm still now try understand what the problem in path

You should not change the setting in the ejs console.
Set the workspace in ejs console back to D:/EJS_4.2.7/workspace/
And move D:\EJS_4.2.7\workspace\source\ahmed\ to  D:\EJS_4.2.7\workspace\source\users\br\ahmed\
If you do not have D:\EJS_4.2.7\workspace\source\users\br\ , you need to create it
then move D:\EJS_4.2.7\workspace\source\ahmed\ to  D:\EJS_4.2.7\workspace\source\users\br\ahmed\

If you change the workspace from D:/EJS_4.2.7/workspace/ to D:/EJS_4.2.7/workspace/source/users/br/ahmed/
Then EJS will try to find source from D:/EJS_4.2.7/workspace/ to D:/EJS_4.2.7/workspace/source/users/br/ahmed/sources/

You can change the directory of workspace to anywhere in your computer.
However, you need to have source/users/br/ahmed/ under the directory of your workspace.

I hope you can understand what I mean.

[ahmedelshfie]

OK prof i do the same i change work speac and back workspace to what you say and
workspace in consol now is "D:/EJS_4.2.7/workspace/"
Workspace in source is"D:\EJS_4.2.7\workspace\source\users\br\ahmed"
So now i will test post simulation again

[ahmedelshfie]

Is the same prof
I do every thing i will send 2 pictures one or path in ejs consul and another
For path of users
When i do it and after convert to jar file he put jar file automatic in export
And when i come to upload simulation  Blackbody Radiation say this message"file ejs_Blackbody_Radiation_Spectrum.jar exists, file will be replaced!"
What mean it prof
Respect

[Fu-Kwun Hwang]

Make sure you use EJS to open the xml source and re-compile to generate new jar file again.

The message is just let you know that you have upload the same jar filename before.
It is a warning message:
It is fine if you really want to replace the previous file.

It is a reminder such that you would not over-write something you have created before (old jar file with the same filename will be replaced with new uploaded jar file)

I check out the jar file you have uploaded last time.

It was ejs_Blackbody_Radiation_Spectrum.jar
However, the xml file in the jar file is BlackbodyRadiationSpectrum.xml
So the output of the jar file should be ejs_BlackbodyRadiationSpectrum.jar
Why you change it to ejs_Blackbody_Radiation_Spectrum.jar

If the xml source is Blackbody_Radiation_Spectrum.xml than the ejs generated jar file will be ejs_Blackbody_Radiation_Spectrum.jar

However, your ejs source is BlackbodyRadiationSpectrum.xml, the generated jar file by ejs should be
ejs_BlackbodyRadiationSpectrum.jar

And please do not use space " " as part of EJS source.

[ahmedelshfie]

 BlackbodyRadiation

Embed a running copy of this simulation
<applet code='users.br.ahmed.BlackbodyRadiationSpectrum_pkg.BlackbodyRadiationSpectrumApplet.class' archive='http://www.phy.ntnu.edu.tw/ntnujava/ejsuser/37048/ejs_BlackbodyRadiationSpectrum.jar' name='BlackbodyRadiationSpectrum5747' id='BlackbodyRadiationSpectrum5747' width='791' height='474' mayscript=true><param name='draggable' value='true'></applet>
Embed a running copy link(show simulation in a popuped window)
<a href='http://www.phy.ntnu.edu.tw/ntnujava/msg.php?smfejs=5747' target='smfejs'>Run simulation</a>

Full screen applet or Problem viewing java?Add http://www.phy.ntnu.edu.tw/ to exception site list
Press the Alt key and the left mouse button to drag the applet off the browser and onto the desktop. This work is licensed under a Creative Commons Attribution 2.5 Taiwan License

• Please feel free to post your ideas about how to use the simulation for better teaching and learning.
• Post questions to be asked to help students to think, to explore.
• Upload worksheets as attached files to share with more users.

Let's work together. We can help more users understand physics conceptually and enjoy the fun of learning physics!

[ahmedelshfie]

Is work Prof
Thank you so much

[Fu-Kwun Hwang]

So you know the rule now. You can upload and create new topic when you make a new simulation.
Keep up the good job! 

[ahmedelshfie]

Thank you Prof be sure about it
Respect
Ahmed

[ahmedelshfie]

In physics, a black body is an idealized object that absorbs all electromagnetic radiation that falls on it. No electromagnetic radiation passes through it and none is reflected. Because no light (visible electromagnetic radiation) is reflected or transmitted, the object appears black when it is cold. However, a black body emits a temperature-dependent spectrum of light. This thermal radiation from a black body is termed black-body radiation.[nb 1]

At room temperature, black bodies emit mostly infrared wavelengths, but as the temperature increases past a few hundred degrees Celsius, black bodies start to emit visible wavelengths, appearing red, orange, yellow, white, and blue with increasing temperature. By the time an object is white, it is emitting substantial ultraviolet radiation.

The term "black body" was introduced by Gustav Kirchhoff in 1860.

Black-body emission gives insight into the thermal equilibrium state of a continuous field. In classical physics, each different Fourier mode in thermal equilibrium should have the same energy. This approach led to the paradox known as the ultraviolet catastrophe, that there would be an infinite amount of energy in any continuous field. Black bodies could test the properties of thermal equilibrium because they emit radiation which is distributed thermally. Studying the laws of the black body historically led to quantum mechanics.

[ahmedelshfie]

Images from http://en.wikipedia.org/wiki/Black_body

[ahmedelshfie]

The Blackbody Radiation Spectrum model shows six fixed-temperature curves between Tmin and Tmax and a red variable-temperature curve that can be adjusted using a slider.
The wavelength is measured in nm (nanometer) and the intensity is measured in W.e-5 / (m2.nm).
Users can adjust Tmin and Tmax to change the temperature range that is displayed.