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An Atwood's machine is a simple mechanical device that consists of two masses connected by a string or rope that passes over a pulley. It is used to study the effects of gravitational forces on the motion of objects.
The pulling force exerted by the string or rope in an Atwood's machine.
The rate at which the velocity of an object changes over time in an Atwood's machine.
When the net force acting on an object in an Atwood's machine is zero, resulting in no acceleration.