1A bone is made of two opposite things
Hard rock-stuff, mixed with bendy rope-stuff
A bone isn't one material. It's two — and they're complete opposites. Watch what each one does on its own:
Hard mineral (the rock)
Stiff like a stone. It barely bends, so it can hold a lot of weight without sagging. But poke it with a sharp jolt and it cracks — like a stick of chalk.
Bendy fibers (the rope)
Springy like a rubber rope. It bends and soaks up a jolt without cracking. But on its own it's floppy — it can't hold you up, it just folds.
2So which one should a bone be?
The chalk stick vs the wet noodle
If you had to pick just one material to build a leg out of, you'd be stuck. Each choice has a problem hiding in it:
The chalk stick
Rock-stiff and strong to lean on — but one sharp knock and it snaps clean through.
The wet noodle
Soaks up any jolt without cracking — but it's so floppy it folds the second you stand on it.
3Your turn — push on a real bone
Press down and feel it give a little
Here's a real bone — hard mineral and bendy fibers woven together. Push the slider to press harder and watch: it doesn't stay stiff like a rod, and it doesn't flop like a noodle. It bends just a hair, then springs back.
4Now try to break it
Build a bone, then drop a weight on it 🏋️
Now you get to choose what the bone is made of, then drop a heavy weight on it from above. Try every recipe — but guess the first one before you drop.
Guess before you drop
Make the bone out of pure hard mineral so it's as strong and stiff as possible. Now drop the weight on it. Does it hold?