atomic force microscope
A microscope that uses a tiny probe mounted on a cantilever to scan the surface of an object. The probe is extremely close to-but does not touch-the surface. As the probe traverses the surface, attractive and repulsive forces arising between it and the atoms on the surface induce forces on the probe that bend the cantilever. The amount of bending is measured and recorded, providing a map of the atoms on the surface. Atomic force microscopes can achieve magnification of a factor of 5 X 106, with a resolution of 2 angstroms, sufficient to resolve individual carbon atoms. Also called scanning force microscope
Tick, Tock: What Is The “Doomsday Clock?”What is the Doomsday Clock? Doomsday is one of those evocative words that paint a very vivid picture. As our definition states, “the day of the Last Judgment, at the end of the world; nuclear destruction of the world; given to or marked by forebodings or predictions of impending calamity; especially concerned with or predicting future universal destruction.” As you can see, it’s about as bottom …
Posthumously And Other Trending Words On Dictionary.com1. Posthumously trended this week (increasing in searches by 102%) as the country still isn’t over the Parkland, Florida school shooting and neither are we. As Marjory Stoneman Douglas High School students went back to school this week, the country (for the most part) applauded the heroism and activism that they’ve displayed. And, they’ve inspired action in all of us too—Dick’s Sporting Goods for the …
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