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 locks work · pin tumbler lock · master key · lock cutaway · how things work · shear line
The real science
Inside an ordinary door lock, five split pins decide which key is allowed to turn. The right key lifts every split to one hidden line, and a wrong key leaves just one pin in the way. Some building locks hide an extra tiny pin that creates a second line, and that's how a master key works.
Don’t try anything shown in this video.
Follow the facts
- Matt Blaze: Rights Amplification in Master-Keyed Mechanical Locks
- Brown University: How a house key works
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#5
#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