How does it work metal wires, and pulleys?
Had a quick chat with a crane operator, using a wire for lifting. Asked what the max load he could lift. He said X amount, but if he uses a pulley, he could lift almost 2 times X.
Is this true? Is there a max to how many pulleys you can use/weight you can lift
Is the lifting curve linear or exponential?
TYIA
In: 20
Wires and ropes work under *tension*. You can’t push a rope. Pulling a rope under tension effectively shortens its length. A pulley redirects a length of rope, which can redirect the forces of that rope.
If you tie one end of a rope to something solid (immovable), run it through a pulley *that’s connected to the load*, and pull on the other end, there end up being *two* sides of the same rope pulling on the load. Your pulling force on the load is effectively doubled. The trade off is that you’d have to pull twice as much rope to move it the same distance as without a pulley.
Max number of pulleys is limited by how much rope you have and how much distance the load needs to travel. Then it’s limited by the tensile strength of your rope/wire.
SmarterEveryDay [did a pretty good video on pulleys](https://youtu.be/M2w3NZzPwOM). I also really like [this video of someone lifting 88kg with a LEGO hoist](https://youtu.be/owv6cOmLGgo).
How does it work metal wires, and pulleys?
Had a quick chat with a crane operator, using a wire for lifting. Asked what the max load he could lift. He said X amount, but if he uses a pulley, he could lift almost 2 times X.
Is this true? Is there a max to how many pulleys you can use/weight you can lift
Is the lifting curve linear or exponential?
TYIA
In: 20
Wires and ropes work under *tension*. You can’t push a rope. Pulling a rope under tension effectively shortens its length. A pulley redirects a length of rope, which can redirect the forces of that rope.
If you tie one end of a rope to something solid (immovable), run it through a pulley *that’s connected to the load*, and pull on the other end, there end up being *two* sides of the same rope pulling on the load. Your pulling force on the load is effectively doubled. The trade off is that you’d have to pull twice as much rope to move it the same distance as without a pulley.
Max number of pulleys is limited by how much rope you have and how much distance the load needs to travel. Then it’s limited by the tensile strength of your rope/wire.
SmarterEveryDay [did a pretty good video on pulleys](https://youtu.be/M2w3NZzPwOM). I also really like [this video of someone lifting 88kg with a LEGO hoist](https://youtu.be/owv6cOmLGgo).
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