Stair Walking Slinky
Sunday Science with Kids
Have you ever tried making a slinky walk down the stairs? It’s easy! The trick is you need a big enough slinky— i.e. you need a slinky long enough and heavy enough.
If talking in physics language this means it needs to have the ‘correct’ spring constant and mass. Spring constant is a measure of how stiff the spring is. If too stiff, it will fold back on itself and stay put rather than walking down the steps. If not stiff enough, it will not have that little ‘spring’ in it to push it over to the next step once it lands on a step and finishes folding onto itself. The ‘mass’ helps in this too — more mass gives it more inertia that helps beat the spring’s natural tendency to keep itself in the folded (stable) state. This link https://guernseydonkey.com/the-joy-of-slinky-the-physics-of-a-metal-marvel/ has a nice explanation of the physics behind it.
Here’s a video of our latest attempt:
All you have to do is to place the slinky at the top of the stairs and give it a little nudge and watch it come to life!
