Pulleys: force and distance
Before you start
How can more rope segments lift the same load with less force?
The setupA continuous gold rope links the wheels and load. A fixed wheel stays on its support; a movable wheel rises with the load. Count only the n strands pulling the moving assembly upward.
What to do and noticePull downward: why does the load rise, and is less force needed? · Why does the required force halve? · For 2 m of rope travel, how far does each load rise?
Predict firstPull downward: why does the load rise, and is less force needed?
How can more rope segments lift the same load with less force?
Prerequisites: A continuous gold rope links the wheels and load. A fixed wheel stays on its support; a movable wheel rises with the load. Count only the n strands pulling the moving assembly upward.A fixed pulley changes direction
Predict firstPull downward: why does the load rise, and is less force needed?
The rope length stays fixed: every metre pulled down raises the load one metre. Only one strand supports it. In slow lifting T = mg, and the hand supplies F = T. The wheel makes the direction convenient without reducing the ideal effort.
How to observe
- Pull downward: why does the load rise, and is less force needed?
- Why does the required force halve?
- For 2 m of rope travel, how far does each load rise?
Model notes
Massless, frictionless wheels and inextensible rope; externally controlled slow lifting with negligible acceleration. All rope segments share the same tension. Mouse input represents rope travel, not physical force feedback. The movable arrangement includes a fixed redirecting wheel.