🪝 I7 Pulleys & Belts

The Gizmo tree house has no stairs, only a rope. Deliveries of snacks, books and a very heavy cat must go up somehow!

Inventors, Intermediate. Engineer Stamp: Pulley Pro.

Lessons

1. The pulley hoist: One pulley changes the direction of the pull. What do two pulleys do?
2. The belt-drive buggy: Belts are like gears that can slip. Is slipping ever a good thing?
3. Pulling power: Can pulleys make you twice as strong? Three times?
4. Belts at work: the conveyor: Factories move thousands of things with belts. Let’s build one!
5. Design Day: Tree-house delivery: The cat has been waiting all day for his dinner basket!
6. Showcase: Tree-House Delivery Day: Every team delivers the basket while the spring scale shows its pull.

Design challenge

Build a lifting system that raises a 300 g basket 40 cm with the smallest pulling force.

Engineering ideas

• Pulleys & Belts
• Torque vs Speed
• Friction

Standards: 3-5-ETS1-2, UK D&T KS2 pulleys