![]() This makes water excellent at sticking to other molecules. The hydrogen end of the molecule is slightly positive, and the oxygen side is slightly negative. WATER CLEANS WELL BECAUSE IT HAS ASYMMETRICAL MOLECULES.īecause water molecules are triangular-made of two hydrogen atoms stuck to one oxygen atom-they have slightly different charges on their different sides, kind of like a magnet. ![]() Water is a great conductor, so it's very effective at transferring that heat or cold to your body. Water's density gives it a high specific heat capacity, meaning it takes a lot of heat to raise its temperature even a little, and it's very good at retaining heat or cold (the reason why hot soup stays hot for a long time, and why the ocean is much cooler than land). DENSITY EXPLAINS WHY COLD WATER FEELS COLDER THAN AIR AT THE SAME TEMPERATURE.īecause water is denser than air, your body loses heat 25 times more quickly while in water than it would in air at the same temperature. So how many people would it take to warm up your home with just body heat in the winter? About 70 people in motion, or 140 people still, figuring that humans radiate 100-200 watts of heat normally and that the house uses four electric storage heaters. People give off body heat, as anyone who has been trapped in a small crowded room knows. YOU COULD HEAT YOUR HOUSE WITH JUST 70 PEOPLE. ![]() Because the surface is more uniform, rays of light bounce back toward your eye more evenly, making it look shiny. When you polish a leather shoe, you coat it in a fine layer of wax, filling in those crevices much like a road crew smoothes out a street by filling in its potholes. Regular leather appears dull to the eye because it’s covered in teeny-tiny scrapes and scratches that scatter whatever light hits the material. POLISHING SHOES IS LIKE FILLING IN A ROAD'S POTHOLES. They are strong enough to support a tower 375,000 bricks tall, or around 2.2 miles high. LEGOs can support four to five times the weight of a human without collapsing. A LEGO BRICK CAN SUPPORT 770 POUNDS OF FORCE. A 1300-foot-tall skyscraper shrinks about 1.5 millimeters under the weight of 50,000 occupants (assuming they weigh about the human average). OFFICE BUILDINGS ARE EVER-SO-SLIGHTLY TALLER AT NIGHT.Īfter all the employees go home, tall office buildings get just a little taller. Now, your bubble gum is made with synthetic rubbers like styrene butadiene (also used in car tires) or polyvinyl acetate (also used in Elmer’s glue) to mimic the effect of chicle. GUM IS CHEWY BECAUSE IT'S MADE OF RUBBER.Įarly gums got their elastic texture from chicle, a natural type of latex rubber. Eventually, all the capsules of glue will get used up or clogged with dirt, and the sticky note won't stick anymore. Thus, you can unstick it, and when you go to attach it to something else, the unused blobs of glue can take over the adhesive role. When you slap a Post-it onto your bulletin board, only some of these blobs (technically called micro-capsules) touch the surface to keep the note stuck there. Post-it Notes feature a plastic adhesive that is spread out in blobs across the paper. STICKY NOTES COME OFF EASILY BECAUSE THEIR ADHESIVE IS UNEVEN. Assuming a typical power drill uses 750 watts of electricity, and it puts out 750 joules of energy, Woodford calculates that it would take just four minutes to set fire to a wooden wall in a 68☏ room. It takes about 2000 joules of energy to heat one kilogram of wood just 1☌. The motor, the drill bit, and the wall all get hot. A POWER DRILL COULD SET YOUR HOUSE ON FIRE, IN THEORY.īecause of friction, electric drills generate heat. Along the way, he also calculates the answers to whimsical questions like, “How many people would I have to gather together to keep my house warm without heat?” (A lot, but not as many as you'd think.) Here are 13 things we learned about the world through his eyes. In his book Atoms Under the Floorboards, author Chris Woodford lays out the abstract science that underlies the everyday world, from the big (how do skyscrapers stay up?) to the small (why does my laptop get hot when I’m watching Netflix?). It explains everything from why bread rises to why you need gas to power your car.
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