NTNUJAVA Virtual Physics Laboratory
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Easy Java Simulations (2001- ) => wave and fluid => Topic started by: ahmedelshfie on April 12, 2010, 03:36:54 am



Title: torsional wave
Post by: ahmedelshfie on April 12, 2010, 03:36:54 am
This applet created by Prof Hwang
Modified by myself
Original project:torsional wave (http://www.phy.ntnu.edu.tw/ntnujava/index.php?topic=1148.0)


Title: Re: torsional wave
Post by: ahmedelshfie on April 16, 2010, 07:45:19 am
This experiment consists of a metal grill that can be twisted to create torsion waves. The waves will reflect off the far end of the grill in either a free or fixed end fashion but the difference is difficult to see unless the students know what to look for exactly.
Image from  http://www.phys.ufl.edu/demo/3_OscillationsWaves/B_WaveMotion/FreeFixedTorsionWaves.html
(http://www.phy.ntnu.edu.tw/ntnujava/index.php?action=dlattach;topic=1545.0;attach=2080)


Title: Re: torsional wave
Post by: Fu-Kwun Hwang on April 16, 2010, 11:05:18 am
The original version (http://www.phy.ntnu.edu.tw/ntnujava/index.php?topic=1148.msg4435#msg4435) was created to simulate a real device.

Please check out New version of torsional wave (http://www.phy.ntnu.edu.tw/ntnujava/index.php?topic=1148.msg5895#msg5895) if you want to simulatate the above demo.


Title: Re: torsional wave
Post by: ahmedelshfie on April 16, 2010, 05:50:04 pm
Here is another version of torsional wave (demostration)

Change the c angle with slider and watch how wave propagate.
The slider for i can be used to change angle for i-th element.

The force acting on each element is
F_i= K* c_i + K_ij * (c_{i+1}-c_i)+K_ij (c_i-c_{i-1})-b*\omega_i
where c_i is the i-th angle, \omega_i is the angular velocity, b is damping constant, K_ij represent interaction between elements.
Original New version of torsional wave (http://www.phy.ntnu.edu.tw/ntnujava/index.php?topic=1148.msg4435#msg4435)