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. A slow push tests stiffness. A sudden impact is a different test that we will try later.
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?
Two recipes before an impact test
These recipes respond differently to a slow load. Inspect their shapes before testing a sudden impact.
A mineral-only rod
The mineral-only rod stays straight under this small steady load. Its impact result has not been shown.
A fiber-only rod
The fiber-only rod bends under a small steady load. How a recipe handles a sudden impact is a separate question.
3Your turn — push on a real bone
Press down and feel it give a little
Here's a model 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 — the recipe that stayed straight under the small steady load. Now drop the weight on it. Does it hold?