NTNU JAVA

Posted: Thu Jan 29, 2004 10:35 am Post subject: Pendulum

How to change parameters?

Click and drag the left mouse button

The horizontal position of the pendulum will follow the mouse Animation starts when you release the mouse button

Stel de juiste lengte in

dragging the pointer (while > holding down the left button)

from the support-point

Change gravity g

Click near the tip of the red arrow

and drag the mouse button to change it (up-down).

Change the mass of the bob

Click near the buttom of the black stick,

and drag the mouse button to change it (up-down).

Information displayed:

K = m v*v /2

U = m g h

Try ro find out the relation between kinetic energy and pontential energy!

will display information for that dot in the textfield

Click show checkbox to show more information

Try to compare velocity and the tangential component of the gravitional force!

The calculation is in real time (use Runge-Kutta 4th order method). The period(T) is calculated when the velocity change direction.

You can produce a period verses angle ( T - X ) curve on the screen,just started at different positions and wait for a few second.

Posted: Fri Jan 30, 2004 4:24 am Post subject:

Subject: Thanks
Date: Wed, 9 Dec 1998 16:07:30 -0500
From: louise heaven <gw_heaven@compuserve.com>
To: Fu-Kwan Hwang <hwang@phy03.phy.ntnu.edu.tw>
Thank you very much Mr Hwang, for your reply to my plea about the pendulum.
I was very pleasently surprized to find you had done so. Thankyou again.
I would also like to say that you have a very good web page and i shall
look there first when i am researching physics.

Joseph Heaven

Posted: Fri Jan 30, 2004 9:39 am Post subject:

From: Bill Kinsella <wkinsella@csi.com>
Reply-To: "wkinsella@csi.com" <wkinsella@csi.com>
To: "'hwang@phy03.phy.ntnu.edu.tw'" <hwang@phy03.phy.ntnu.edu.tw>
Subject: Java Applets
Date: Sat, 6 Nov 1999 21:04:16 -0000

Dear Sir,

I came across your site when I was searching for material for my son who is
studying science and in particular the pendulum. I was facinated by the
immediacy and effficacy of the applets. Surely this must represent a major
advancement in the teaching of physics as well as being great fun.

Unlike you I spent most of may life as a software developer although I know
nothing of Java type languages and now work as a power company nework
controller an can think of many interactive applications for our intranet.

I would like to see an applet developed illustrating the principles of
simple roof truss design.

Thanks for the enjoyment your work provided,

Bill Kinsella

Posted: Mon Mar 22, 2004 6:55 am Post subject:

From what I learned in physics. The equation for the period of a simple pendulum is T=2(pi)(L/G)^1/2. Which means constant length should result in constant period. However I change the angle of release on the pendulum and the period changes!!??.