The Swinging Atwood's Machine Model is an extension of the traditional Atwood's machine where one hanging mass is allowed to swing like a pendulum. One assumes that all motions for the swinging mass are possible including positions above the second peg which requires that the string remains rigid at all times. Unlike the traditional Atwood's machine, orbits or cycles are possible. In other words, for certain conditions, the motion of the Atwood's machine can continue indefinitely. In changing the ratio of the two masses and the initial angle of displacement, the trajectory of the swinging mass changes.  The object of this simulation is to model that system and allow the user a large amount of control over initial conditions so that they may fully explore the system.

The Swinging Atwood's Machine Model was created using the Easy Java Simulations (EJS) modeling tool.  It is distributed as a ready-to-run (compiled) Java archive.  Double clicking the ejs_comp_phys_swinging_atwoods.jar file will run the program if Java is installed.

Please note that this resource requires at least version 1.5 of Java (JRE).