Ejs open source java applet Resonance simple harmonic motion SHM

[lookang]

Ejs open source java applet resonance is the tendency of a system to oscillate at maximum amplitude at certain frequencies, known as the system's resonance frequencies. Experiential learning activity by lookang


click on the jar file on the next post of the applet!
also available here http://www.phy.ntnu.edu.tw/ntnujava/index.php?topic=494.msg1541#msg1541

This Interactive Resource was designed by: Wee Loo Kang
not my best work , still unpolished due to limited skills in coding.

Embed a running copy of this simulation
<applet code='users.sgeducation.lookang.weelookangresonance10moe_pkg.weelookangresonance10moeApplet.class' archive='http://www.phy.ntnu.edu.tw/ntnujava/ejsuser/14019/ejs_weelookangresonance10moe.jar' name='weelookangresonance10moe2996' id='weelookangresonance10moe2996' width='1024' height='695' 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=2996' 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!

[lookang]

let me know if you find bugs!

Objective
9745 H2 PHYSICS (2008) 8. Oscillations Damped and forced oscillations: resonance (k) describe graphically how the amplitude of a forced oscillation changes with frequency near to the natural frequency of the system, and understand qualitatively the factors which determine the frequency response and sharpness of the resonance.

Make Learning Deep and Sense Making
Resonance
For a forced oscillation, when the driving frequency is equal to the natural frequency of the oscillating system, maximum energy is transferred from the periodic force (driver) to the oscillating system which will vibrate with maximum amplitude. This phenomenon is called resonance.

Frequency Response Graph (under different degrees of damping)
The Effect of Damping on Forced Oscillations
When damping is present, it reduces the amplitude (y-axis) of the forced oscillation for all driver frequencies (x-axis) and it causes the maximum amplitude to be reached when the driving frequency is a little less than the natural frequency.
This reduction in amplitude is more significant at the resonance frequency and frequencies close to it, so that we say damping reduces the sharpness of resonance -- that is, the oscillating system responses little (small change in the amplitude) over a wide range of frequencies.
source code
download the *.jar for using the applet on standalone without internet connection.

[lookang]

Changes made to make it compiled in ejs 4.2.

From "Spring-Mass System for 'A' level Physics, Oscillations, Damping, Resonance by weelookang@gmail.com homepage: http://lookang.co.nr"
to "Spring-Mass System for -A level Physics, Oscillations, Damping, Resonance by weelookang@gmail.com homepage: http://lookang.co.nr"

strangely a disabled page is also causing compiling issues.
the code is _pause()
seems to be not recognized in ejs 4.2

[lookang]

found a cool Resonance applet with mathematical model to plot the theory frequency response from Prof Wolfgang.
will try to combine into the top java applet.

[lookang]

found this to be very similar, worth looking them
http://www.myphysicslab.com/spring1.html by Erik Neumann
Like: the theory and explanation and to do exercises