## Exploration 4.7: Atwood's Machine

Set ratio of masses: M / m =
Note: you must keep the ratio above 0.25 and below 10.

Please wait for the animation to completely load.

A 10-kg mass, M, is attached via a massless pulley to another variable mass m (position is given in meters and time is given in seconds). You can test the limits of the formula for the acceleration of the Atwood's machine (not shown to scale) by changing the ratio of the masses above. Restart.

1. Draw a free-body diagram for each mass.
2. Solve for the acceleration of m in terms of g, M, and m.
3. Which, if any, of the following statements regarding the motion of the masses are true?
• when M = m then: a = g.
• when M = m then: a = 0.
• when M >> m then: a = g.
• when M >> m then: a = 0.
• when M < m then: a = 0.
• when M < m then: a = g.
• when M < m then: a < 0.

Verify your answer(s) to (c) by using the animation and your answer for (b).

Physlets were developed at Davidson College and converted from Java to JavaScript using the SwingJS system developed at St. Olaf College.