In an Atwood machine with masses m1 > m2, which mass experiences downward acceleration?

In an Atwood machine with masses m1 > m2, which mass experiences downward acceleration?

• A. m2
• B. m1
• C. Both masses
• D. Neither mass

Answer: (B)

In an Atwood machine with a massless rope over an ideal pulley, the two masses share the same magnitude of acceleration but move in opposite directions. The heavier mass pulls downward because its weight difference from the lighter mass creates a net downward force on that side, while the lighter mass is pulled upward with the same acceleration magnitude. Therefore, the mass that goes downward is the heavier one. The lighter mass does not descend, and saying “neither” would ignore the actual acceleration, while saying both would ignore the opposite directions of motion.

In an Atwood machine with a massless rope over an ideal pulley, the two masses share the same magnitude of acceleration but move in opposite directions. The heavier mass pulls downward because its weight difference from the lighter mass creates a net downward force on that side, while the lighter mass is pulled upward with the same acceleration magnitude. Therefore, the mass that goes downward is the heavier one. The lighter mass does not descend, and saying “neither” would ignore the actual acceleration, while saying both would ignore the opposite directions of motion.