Quote (FaceDeath @ Mar 24 2017 08:26pm)
https://en.m.wikipedia.org/wiki/SlinkySlinky is a toy, a precompressed helical spring invented by Richard James in the early 1940s. It can perform a number of tricks, including travelling down a flight of steps end-over-end as it stretches and re-forms itself with the aid of gravity and its own momentum, or appear to levitate for a period of time after it has been dropped.
This page
Physical properties Edit
The rules that govern the mechanics of a slinky are Hooke's law and the effects of gravitation.
Period of oscillation Edit
Due to simple harmonic motion the period of oscillation of a dangling slinky is
T
Where T is the time of the period of oscillation, m is the mass of the slinky and k is the spring constant of the slinky.
Equilibrium Edit
In the state of equilibrium of a slinky, all net force is cancelled throughout the entire slinky. This results in a stationary slinky with zero velocity. As the positions of each part of the slinky is governed by the slinky's mass, the force of gravity and the spring constant, various other properties of the slinky may be induced. The length of a perfect slinky with zero length when extended is
L
Where L is the length of the slinky, W is the weight of the slinky, and k is the spring constant of the slinky.
Due to the effect of gravity, the slinky appears bunched up towards the bottom end, as governed by the equation
p
Where n is a dimensionless variable, 0 ≤ n ≤ 1, with n = 0 corresponding to the top of the slinky and n = 1 being the bottom. Each intermediate value of n corresponds to the proportion of the slinky's mass above that point n, and p(n) gives the position that n is above the bottom of the slinky.
This quadratic equation means that rather than the center of mass being at the middle of the slinky, it lies one quarter of the length above the bottom end,