Physical Science
Physical science is the study of the physical world around you. Learn about everything from electricity to magnetism in this section.
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Criminals always leave traces behind after a crime is committed. In fact, footprints, tire tracks and tool marks are often more prevalent than fingerprints at a crime scene. What can impression evidence tell an investigator?
By John Fuller
The idea that something so intangible as acoustic levitation can lift objects may seem unbelievable, but it's a real phenomenon.
When there's a suspect in a crime and the evidence includes a handwritten note, investigators may call in handwriting experts to see if there's a match. How exactly do experts go about analyzing someone's handwriting?
By Julia Layton
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Iran has announced its activation of a second set of uranium centrifuges. These machines are at the core of the uranium-enrichment process. Find out where the centrifuge fits into the equation.
A venerable work of art hangs lifeless in a museum, the once brilliant scene dulled by centuries of dirt and grime. Can laser analysis and modern art restoration techniques save the masterpiece?
We love it. We wear it glittering around our necks and sparkling at our ears, wrists and feet. We pass it down to our children and hoard it in secret stashes. Why is this precious metal so prized?
Can you pass the acid test? That electric Kool-Aid changed the fabric of 1960's American counterculture. So, what's it's like to trip on LSD?
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Mushrooms - they're not just a pizza topping. This psychotropic fungus has guided many an adventurer on a trip. How do shrooms make their magic?
We once emptied the scent pods of male musk deer into a bottle of fragrance and doused it on, feeling like a million bucks. How has perfume changed since then?
Unlike the cheap microscopes you peered into in school, these advanced instruments can breathe rich detail into the tiny world around us, including the world of nanotechnology.
It begins with an unassuming "H" and ends in crazy elements that you've likely never heard of. But the periodic table, encapsulated on a mere sheet of paper, can be a scientist's best friend and a testament to our human drive to organize the world.
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Mass spectrometry enables the major league to sniff out athletes guilty of doping. It can also help us locate oil or design a killer perfume. Who says chemistry isn't cool?
First, you burn the body until only brittle, pulverized bones are left. These remains are pulverized into ashes, and then placed into urns -- or diamonds, coral reefs and even outer space.
By Michelle Kim
Once considered a semiprecious metal alongside gold and silver, aluminum pretty much languished in obscurity until the 19th century. How did the metal become so ubiquitous?
Overtone is a sound accompanying the main tone produced by a vibrating body. The number and loudness of overtones determine the timbre, or tone color, of a musical sound.
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An object free to vibrate tends to do so at a specific rate called the object's natural, or resonant, frequency.
When sound waves strike the ear, these waves produce the sensation of sound. Let's take a look at how sound waves work.
If you want to see a hologram, you don't have to look much farther than your wallet. But the most impressive holograms are large scale and illuminated with lasers or displayed in a darkened room with carefully directed lighting. Learn how a hologram, light and your brain work together make clear, 3-D images.
When it comes to stimulating the human central nervous system, meth can hold its shaky, toothless head high. Why is this drug so additive?
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If the sight of a mushroom cloud burning above the horizon suggests that the nuclear weapon-equipped world might end with a bang, then nuclear winter presents the notion that post-World War III humanity might very well die with a whimper.
By Robert Lamb
One of the most influential ideas in forensic science history is known as Locard's exchange principle. This simple, yet groundbreaking idea forever changed the way we fight crime. But who was Edmond Locard, anyway?
By John Fuller
Imagine walking through a field and stumbling upon scads of corpses, all in various states of decomposition. It's not the setting for your next nightmare, but rather a very real discipline of forensic anthropology.
By Tom Scheve
The Fibonacci sequence has been a numerical sequence for millennia. But what does it have to do with sunflower seeds or rabbits?
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In the comics, radiation exposure turned an average man into a pea green and angry Incredible Hulk. But in reality, what can radiation do to those exposed? Is it always a villain?
By Debra Ronca
If the idea of being completely knocked out by a cocktail of drugs while doctors operate on you freaks you out, you're not the only one. But that's not what anesthesia is all about it - and it might scare you less if you understand how it works.