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Levitating Graphene Is Fastest-Spinning Object
techbeat writes "A flake of exotic carbon a few atoms thick has claimed a record: the speck has been spun faster than any other object, at a clip of 60 million rotations per minute. Previously, micrometre-sized crystals have been spun at up to 30,000 rpm using an optical trap. It is thanks to graphene's amazing strength that the flakes are not pulled apart by the much higher spinning rate, says Bruce Kane at the University of Maryland in College Park. Spinning could be a way to probe the properties of graphene, or manipulate it in new ways."
can you give it enough mass to make it into a decent flywheel?
No typo. Read the original abstract: http://www.ncbi.nlm.nih.gov/pubmed/19424395
500 turns per second. But your HD isn't put to rotation by a light beam - that's the news of this article, not the speed.
Next time you teach someone to drive a manual, don't let them touch the accelerator until they learn how to use the clutch..?
which is totally what she said
No wait, even if we have a video that ran at one million frames per second all we would see is an immobile object. At two million frames per second we would see it move instantly by 180 degrees... How did they calculate that 60 million rotations per minute again?
They shoot a laser beam through the sample, which they measure with a detector at the other side. Then they apply an electric field to the flakes at high frequency (> 1 MHz). They scan the frequency of the electric field from 4 kHz up to 3MHz. When the frequency of the electric field is the same as the frequency of the rotating flake you get a resonance which appears as a sudden spike in the laser detector. That's how they know what the rotation rate is, and the dielectric response of graphite to an electric field is well known so they can cross check this with theory.
...and technically we do have video systems that can acquire data up to 1 peta Hz (or if you're american you'd say 1 quadrillion Hz). Femtosecond lasers are used in chemistry for more than a decade now to image fast chemical reactions.
Hope this rambling post helps!
And avoid girlfriends who think it's OK to twist and pull the stick shift violently, whether it's ready or not. Could be indicative of future, uh, problems.
God invented whiskey so the Irish would not rule the world.