Pulley

How it works

• Two cups hang on one cord over two wheels. The cord's total length is fixed, so when one cup goes down the other goes up.
• Whichever cup carries the heavier load goes down.
• The cups stay level, but they swing sideways a little when loaded off-centre.
• A flip button swaps which cup hangs lower at the start.

Tips

• Leave room around the cups. They swing sideways when the load is off-centre.
• A bucket slowly filling with water makes a weight that grows, which suits a pulley well.

Where you'll meet it

You first meet it in level 24, Counterweight, in chapter 3, Strings Attached.

Works with

• Bucket
• Water Tank
• Anvil
• Crate
• Rope