The Java Video Physics Lab

Screen capture of the Java Video Physics Lab. An applet for elementary physics education using video of real masses in motion. Click here to see more screen captures.
The Java Video Physics Lab applet is intended for use in introductory physics education. It offers physics students the chance to investigate laws of motion and kinematics by doing "virtual experiments" using digitized video. The applet can be used within a Web page that the instructor writes which may include a description of what the student should look for and how the student should use the selected video.

The Java Video Physics Lab applet is useful for illustrating the following physical concepts:

Acceleration is the change in velocity over time.
A projectile has constant horizontal speed.
A projectile has constant vertical acceleration, a ~ -9.80 m/sec².
During an elastic collision, both momentum and kinetic energy are conserved.
During an inelastic collision, momentum is conserved but kinetic energy is lost.
During a collision, the force of mass #1 on mass #2 is equal and opposite to the force of mass #2 on mass #1 (Newton's 3rd Law).

The videos available for use with the Java Video Physics Lab applet include:

A projectile shot straight up and falls down.
A projectile shot at a 45^o angle.
A ball rolling of the edge of a table and bouncing off the floor.
A pendulum and a mass on a spring.
Two masses undergoing both elastic and inelastic collisions.
A double pendulum, illustrating chaotic motion with damping.
And several others, with new ones to be added.
Can be used with any 320 x 240 AVI, MPEG, or QuickTime video files depicting one or two masses in motion.

System requirements for the applet are:

A Pentium 90 class system or better with a plugin compatible web browser installed.
The Intel Java Media Framework SDK installed, available here.
Sun's Java Plugin installed, this makes any plugin compatible web browser FULLY Java 1.1 aware (and the right kind of Java 1.1 aware too), available here.

The Java Video Physics Lab applet is easily modified by changing the applet script.
Below is an example of the user modifiable portion of the applet script.

//The following are user defined variables
/*The name of the video file in AVI, MOV, or MPG format.*/ file="projectile.mov" 
/*The scale factor in cm/pixel.*/                          ScaleFactor="0.728"
/*The time interval between samples in milliseconds.*/	   TimeInterval="67"
/*The number of measurements to make.*/                    NumberOfPoints="10" 
/*The number of masses in the video.*/                     NumberOfMasses="1"
/*Magnitude of mass #1 in grams.*/                         Mass1="200.0"

Copies of the Java Video Physics Lab applet for noncommercial use can be obtained by writing the author, Phillip Dukes, at phil.dukes@utb.edu.