Oh no! The elves can’t lift their Christmas treats up the stairs, can you design a pulley system to help them?
A pulley is made up from one or more wheels with a rope looped over them to make it easier to lift objects. The more wheels the pulley has the easier it is to lift the load. We designed a very simply pulley system inside a cardboard box, but you could make yours much bigger.
- Thick string or rope
- Small container or bucket if you want to make a bigger version.
- Pulley or Metal loop or ribbon spool. We used this pulley from The Consortium.
- Small objects to lift
Attach a small container onto the end of a piece of string or rope.
Thread the string through a suspended metal loop or over a pulley. Add enough Christmassy weight to the container so it is hard to lift by hand and pull up using the rope. You’ll need to scale this acccording to how strong your pulley is. Ours is just a model of a pulley rather than a helpful device.
Try again using a ribbon spool instead of a metal ring, is it easier or harder to pull the container upwards this time?
Things to think about
How long does the string/rope need to be?
Is it easier to lift the bucket with or without the pulley?
What would happen if you used thicker or thinner string or rope?
Can you make a larger scale version if you started small?
How would you change your design?
Can you design a double pulley? Is it easier or harder to lift the object attached?
Try using smooth and rough rope, is one easier to pull than the other?
Links with English
Can you write a list of safety rules the elves should follow if they use a pulley in Santa’s workshop?
Links to Maths
Place your items in order of how much they weigh, then in order of size. Does the order change much?
More Christmas Science Ideas
Have you seen these STEM Stocking Fillers?
We like the look of this pulley set too.