# If two identical masses

• Aug 16th 2006, 10:22 AM
Refujoi
If two identical masses
If two identical masses are attached by a light cord which is passing over a mass-less, frictionless pulley of an atwood's machine, but at different heights, and then realesed:

1) the masses will not move.
2) the higher mass will go down.
3) the motion will depend on the amount of the masses.
4) the lower mass will go down.
• Aug 16th 2006, 11:55 AM
topsquark
Quote:

Originally Posted by Refujoi
If two identical masses are attached by a light cord which is passing over a mass-less, frictionless pulley of an atwood's machine, but at different heights, and then realesed:

1) the masses will not move.
2) the higher mass will go down.
3) the motion will depend on the amount of the masses.
4) the lower mass will go down.

1) the masses will not move.

You can set up the mathematics for the problem, but we can "logic" this one out. The largest mass in the Atwood machine will accelerate downward. Since the masses are equal there is no acceleration. The height does not matter.

-Dan