Insights The Slinky Drop Experiment Analysed

AI Thread Summary
The slinky drop experiment demonstrates the principles of mechanical equilibrium and conservation of momentum using a simple toy. It involves suspending a slinky and observing its behavior as it drops, ideally recorded with a smartphone for clarity. The discussion highlights the evolution of the slinky's shape during the drop, emphasizing the importance of understanding its displacement field and material variables. Participants also share insights on refining the analysis, including considerations for the slinky's non-zero rest length. Overall, the experiment serves as an engaging way to explore fundamental physics concepts.
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2006-02-04_Metal_spiral.jpg
Figure 1: A slinky, the subject of the slinky drop experiment. Attribution: Roger McLassus. CC BY-SA
The slinky drop is a rather simple experiment. In its most basic form, it requires only a popular toy for children, a stable hand, and a keen eye. For a better view, using a modern smartphone to capture a video of the experiment also helps to capture the falling slinky. Apart from the commonly quoted result, Insight will discuss the evolution of the slinky shape during the drop using only high-school physics: mechanical equilibrium and the conservation of momentum.

What is The Slinky Drop Experiment?
The slinky drop experiment is exactly what it sounds like:

Support a slinky at one of its ends. Let the rest of it hang freely under...

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Oh you beat me to it! It seems that you finally used my suggestion of using the displacement field! I have a similar solution that I might share later.
 
pines-demon said:
Oh you beat me to it! It seems that you finally used my suggestion of using the displacement field! I have a similar solution that I might share later.
No, the displacement field is still the dependent variable. The slinky fraction ##s## is the independent material variable. This is the way I did it from the beginning.

The only addition is a non-zero rest length of the slinky. Otherwise the analysis is the same as my post #5 of that thread, just a bit more polished.
 
Orodruin said:
The only addition is a non-zero rest length of the slinky.
I was talking about that.
Orodruin said:
Otherwise the analysis is the same as my post #5 of that thread, just a bit more polished.
Thanks for the clarification. Anyway, great article!
 
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