Wild Insides
#5How things work
Why Shopping Carts Lock Up At The Parking Lot Edge
Some shopping carts have a hidden brake in one wheel.
Short. Strange. True.The real science
how it works · gas pump · fuel nozzle · venturi effect · automatic shutoff · physics explained
The real science
A gas pump nozzle shuts itself off when your tank is full, with no sensor, chip or electricity. Everything happens in one tiny hole near the tip, a thin air tube and a rubber diaphragm, all driven by the Venturi effect. Here is the whole mechanism, step by step, in a cut-away view.
Don’t try anything shown in this video.
Follow the facts
- HowStuffWorks: How Does a Gas Pump Know When to Stop?
- Hagerty: How the Venturi effect enables gas pump shutoffs
- ScienceABC: How Does The Gas Pump Automatically Shut Off?
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#3How things work
Why A Snapped Elevator Cable Won't Drop You
Almost everyone has wondered what happens if an elevator's cable snaps.
Short. Strange. True.The real science
#2How things work
How Pill Bottle Caps Outsmart Most Toddlers
Child-resistant medicine caps hide a two-part lock that only opens when you push down and turn at the same time.
Short. Strange. True.The real science