Slinky City


What happens when you give kids a bunch of slinkies and take them out in the city?  THIS:

Spent Slinkies

But how did this happen?!?

First, we attempted to catch a perfectly coiled slinky on our foreheads which proved very difficult. Those little coils have more energy and momentum than we thought! 

We learned about physics through videos, play, and by taking to the streets, hills, slides, and stairs of San Francisco with slinkies in hand. 

We made predictions about how our slinkies would behave in various situations. What would happen to a stretched slinky strung between two chairs on a string when you let go of both ends at once? What would happen to a slinky on a slide? Down a hill? Down the stairs? How would a slinky drop if held outstretched out of a window? With Newton in mind, we took off to test our inquiries.

The most shocking was this one, which you can hear about on RadioLab or watch an explanation of it here.

In search of the perfect stairs for our giant slinky to descend, we became enamored with the Seward concrete slides. Though they were closed for the day, they provided an excellent testing ground for many of our ideas. We discovered that slides lack the friction needed for slinkies to walk themselves down, but we found great delight in using the potential energy of the slide to create a rainbow avalanche! Admittedly, our slinkies didn't fare well in this experiment, but we were not deterred.

Behold the potential energy!

We never did find any stairs that our slinkies could successfully walk down, so we did the next logical thing: we built our own! 

 Success at last! 

Success at last! 

Inspired by this intense video of a slinky persistently marching on a treadmill, we attempted to make our own out of materials found around the house (bicycle, a roll building paper, broom handles, and duct tape), which... failed. Failure is good! We learned that our bike tires didn't have enough traction to produce the needed friction to make our conveyor belt slide over the handles of brooms. Lesson learned. But check out how cool this is!

Phew! What a day! The slinkies weren't the only ones spent by the end of it... 

To capture our day, the kids made this video in summary, with a healthy dose of slow-motion humor for your enjoyment. 

Our slinkyists created this video capturing the essence of our slinky physics play for the day.

Still can't get enough? Check out these amazing resources from the Exploratorium!

  • Slinky in Hand - "With just a Slinky and your hands, model transverse wave resonances as well as longitudinal wave resonances. Learn about nodes and antinodes of motion and compression."
  • Seismic Slinky - Explore the many waves of earthquakes using a slinky
  • Giant Slinky Exhibit