Catenary HoodieTHE CHAIN FINDS THIS CURVE | Pixelated PhysicsHoodie
Catenary Hoodie – THE CHAIN FINDS THIS CURVE | Pixelated Physics
- Color
- Black
- Size
- S–5XL
- Made
- To order · shipping times
What shape does a hanging chain make? Not a parabola, though it looks close. A uniform flexible chain settles into the catenary, y = a cosh(x/a), the shape with the least potential energy for its length. Jakob Bernoulli posed the problem in 1690, and Huygens, Leibniz and Johann Bernoulli solved it in 1691. Black pixel-art hoodie; equation, symbols and sources in the physics panel below.
Size guideS–5XL · inches
Couldn't load pickup availability
Free US shipping$10 flat shipping outside the USMade to order, ships in 2–5 business days
Details
Size & fitS–5XL
Unisex Heavy Blend hoodie (Gildan 18500), classic fit.
| Size | Width | Length | Sleeve |
|---|---|---|---|
| S | 20 | 27 | 33.5 |
| M | 22 | 28 | 34.5 |
| L | 24 | 29 | 35.5 |
| XL | 26 | 30 | 36.5 |
| 2XL | 28 | 31 | 37.5 |
| 3XL | 30 | 32 | 38.5 |
| 4XL | 32 | 33 | 39.5 |
| 5XL | 34 | 34 | 40.5 |
Measurements in inches. Width and length ±1 in, sleeve (from center back) ±0.75 in.
ShippingFree US
Free US shipping. $10 flat shipping outside the US.
Returns & replacements21 days
Every item is printed to order, so we can’t accept returns or exchanges for change of mind, or if you ordered the wrong size or colour.
Print defect, misprint, damage or the wrong item? We’ll send a free replacement, or a refund if you prefer. Report it within 21 days of delivery with a photo; no need to send it back.
∂ The physics
A uniform flexible chain hangs under gravity between two supports. What shape does it take?
Not a parabola. The shape that minimises potential energy for a given length is the catenary y = a cosh(x/a). Local tension satisfies T = μ g y.
A parabola through the same apex and endpoints is close — the largest gap is about 8.7 px, roughly 8.7 % of the 99.9 px sag — but the Euler–Lagrange identity y/√(1+y′²) = a holds only for the cosh.
On the front, the filled arch is the catenary; the thin magenta ghost is the matched parabola for contrast.
Jakob Bernoulli posed the problem in 1690; Huygens, Leibniz and Johann Bernoulli published the cosh solution in 1691.
Equations
| Symbol | Meaning | Unit |
|---|---|---|
| \(y\) | height of the cable above the directrix | \(\mathrm{m}\) |
| \(x\) | horizontal distance from the vertex | \(\mathrm{m}\) |
| \(a = T_0/(\mu g)\) | shape parameter (horizontal tension over weight per length) | \(\mathrm{m}\) |
| \(T\) | local tension | \(\mathrm{N}\) |
| \(\mu\) | mass per unit length | \(\mathrm{kg/m}\) |
| \(g\) | gravitational acceleration | \(\mathrm{m/s^2}\) |
| \(V\) | gravitational potential energy of the cable | \(\mathrm{J}\) |
Sources
- Bernoulli, Leibniz, Huygens (1691) solutions to the hanging-chain problem posed by Jakob Bernoulli
- Halliday, Resnick & Walker, Fundamentals of Physics (catenary / hanging cable notes in continuum mechanics supplements)
- Taylor, Classical Mechanics (2005), variational problems and the catenary
- Weisstein, Catenary, MathWorld (opens in a new tab)
Field notes
View all-
What Are Gluons, and Why Can’t We See a Single ...
Every proton holds three quarks, yet no experiment has ever pulled a single quark free. The reason is the strange behaviour of gluons, the carriers of the strong force. Here...
What Are Gluons, and Why Can’t We See a Single ...
Every proton holds three quarks, yet no experiment has ever pulled a single quark free. The reason is the strange behaviour of gluons, the carriers of the strong force. Here...
-
Can Temperature Be Negative? Negative Absolute ...
Physicists have made systems with negative absolute temperature since 1951. They are not colder than absolute zero; they are hotter than any positive temperature. Here is why, what was measured,...
Can Temperature Be Negative? Negative Absolute ...
Physicists have made systems with negative absolute temperature since 1951. They are not colder than absolute zero; they are hotter than any positive temperature. Here is why, what was measured,...
-
Why Does a Magnet Fall Slowly Through a Copper ...
Copper isn’t magnetic, yet a strong magnet dropped down a copper pipe falls in slow motion. The reason is Lenz’s law: the currents the moving magnet induces always push back...
Why Does a Magnet Fall Slowly Through a Copper ...
Copper isn’t magnetic, yet a strong magnet dropped down a copper pipe falls in slow motion. The reason is Lenz’s law: the currents the moving magnet induces always push back...