# If two identical masses

#### 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.

#### topsquark

Forum Staff
Refujoi said:
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

#### Monoxdifly

What is an Atwood's machine?

#### romsek

MHF Helper
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
They should specify a massless rather than "light" cord.

Pedantically the longer length of cord will contribute more mass to one side than the other.

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