World's Longest Straw

A “world’s longest straw” challenge turns into a lesson on the physics of suction: no matter how determined someone is, the maximum height a person can lift a liquid with a straw is capped by atmospheric pressure and the weight of the liquid column. The experiment first demonstrates that sucking through long tubing is possible—then shows where it breaks down.

In the opening round, straws are taped together and tested at about 1 meter, where air leaks at the joints make the setup unreliable. The team switches to a 6-meter length of plastic tubing and runs a controlled comparison: Nigel attempts to suck coke up the full length, while another attempt uses thicker tubing (about 5 mm diameter versus Nigel’s 3 mm). Nigel succeeds with the 6-meter tubing, reaching the full height and drawing cheers—confirming that suction can pull liquid surprisingly far when the path is sealed and the diameter is workable.

The next challenge pushes toward the theoretical limit. At Tamarama Beach, 10.5 meters of tubing runs from the top of a cliff down to a reservoir of red liquid. Nigel starts sucking, but the liquid stalls around 7 meters rather than rising to the expected maximum near 10 meters. The failure isn’t framed as a lack of effort; it’s treated as a limitation of real-world suction. The “theoretical maximum” assumes a perfect vacuum in the mouth—an ideal that humans can’t actually produce.

That gap leads into the core explanation: a straw doesn’t “pull liquid” by magic. It works because lowering pressure in the mouth creates a pressure difference relative to atmospheric pressure. Atmospheric pressure then pushes the liquid up into the region of lower pressure. The height the liquid reaches depends on balancing the pressure difference against the weight of the liquid column inside the straw.

Using the physics of pressure and fluid weight, the maximum vertical lift comes out to about 10.3 meters for water-like conditions, even with a perfect vacuum. The transcript connects this to historical barometer measurements: atmospheric pressure was once measured by how high it could push mercury in a tube—about 760 millimeters of mercury at standard pressure. Mercury’s high density makes the required tube length manageable; doing the same with water would require an impractically tall “barometer,” on the order of a ten-meter cliff.

By the end, the challenge lands on a clear takeaway: the longest straw isn’t limited by technique or even tubing diameter alone, but by the fundamental ceiling set by atmospheric pressure and the inability to create a perfect vacuum. Nigel’s best attempt reaches roughly 7 meters—impressive, but still below the 10.3-meter theoretical limit—turning a stunt into a quantitative demonstration of how suction really works.