Latest posts from the blog
Wrapping something in a wet cloth and pointing a fan at it is a genuinely good way to cool a warm drink — and one of the fastest ways to ruin a frozen one. Evaporative cooling bottoms out at the wet-bulb temperature, and a damp cloth conducts heat far better than still air even while sitting cooler than the room. We check what it actually takes to hold a low temperature without a refrigerator.
The vacuum of space is popularly imagined as cold enough to flash-freeze anything exposed to it. But a vacuum has no air or water to carry heat away, so conduction and convection simply don't happen there — only radiation does, and radiation is slow. That's why the ISS carries a 70 kW ammonia cooling loop, why spacesuits are built to fight overheating rather than frostbite, and why Google named cooling as its hardest problem in putting AI data centers in orbit. We check the Stefan-Boltzmann law against the real engineering, and against the one detail *2001: A Space Odyssey* got backward.
Is the "antioxidant" on an instant noodle label secretly a preservative in disguise? We check how frying drives moisture down to 4-6%—low enough to starve microbes—and how the Codex food standard lists preservatives and antioxidants as entirely separate categories, using water activity (Aw) thresholds as the yardstick.
The tomato debate is old news — the U.S. Supreme Court settled it in 1893 by ruling it's botanically a fruit but legally a vegetable. Strawberries and watermelon raise a stranger question: can one government's own rules disagree with each other about what counts as fruit?
A bottle bursts in the freezer because water expands when it freezes — but is water really the only substance that does this, and could enough pressure stop it? We trace the mechanism through hydrogen bonding and ice's hexagonal crystal structure, then check what the physics actually says about both questions.