Atwood's machine

Mass of block 1 (on the left)
0.1 kg 2.0 kg
Mass of block 2 (on the right)
0.0 kg 2.0 kg
Mass of the pulley
0.0 kg 2.0 kg
The pulley is a

The simulation illustrates an Atwood's machine, which is simply two blocks connected by a string passing over a pulley. Unlike the previous version of the simulation, in which the mass of the pulley was negligible, here we account for the mass of the pulley. That leads to the tension in the string being different on the two sides of the pulley, when the system is accelerating.

Given the limits on the sliders in the simulation, and the fact that the simulation uses 10.0 m/s/s for g, what are the most positive and most negative values that can be obtained for the acceleration when the pulley mass is 1.0 kg?

Note that the pulley has two additional forces that are not shown. These are the downward force of gravity, and the upward normal force (which must balance all the downward forces) - they are omitted because, passing through the center of the pulley, they do not contribute to the torque about the center.

Simulation first posted on 8-26-2016. Written by Andrew Duffy

Creative Commons License
This work by Andrew Duffy is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License.
This simulation can be found in the collection at

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