Worth a Look Archive - Page 2
Music Acoustics: How does a guitar work? - Jun 1, 2012
To learn more about the physics of the guitar, including acoustic guitars, visit Music Acoustics: How does a guitar work?.
Torque - May 1, 2012
Visit Torque for photographs that show a horizontal beam fastened to a support at one end, with a weight hung on the beam at different distances from the support. You'll see how the distance of the weight from the support affects how much the beam bends--the further the distance, the greater the torque.
Hyperphysics: X-ray tube - Apr 1, 2012
X-ray tubes work by firing electrons at a metal plate in a vacuum. When an electron passes near the nucleus of one of the atoms in the plate, it is accelerated and emits x-rays, as shown in the drawing on this Hyperphysics page. To learn more, visit Hyperphysics: X-ray tube.
Molecular Chirality - Mar 1, 2012
Both amino acid molecules (the building blocks of proteins) and sugars can be right- or left-handed, and the way they react chemically depends on their handedness. To find out how handedness is important in our diet, and in drugs, visit Molecular Chirality.
Space Topics: Extrasolar Planets--Searching Methods - Feb 1, 2012
There are five ways to detect an extrasolar planet:
How Airplanes Fly: A Physical Description of Lift - Jan 1, 2012
Visit the Florida International University site How Airplanes Fly: A Physical Description of Lift to understand how the wing of an airplane produces lift. You'll see that the frequently-given explanation based on the Bernoulli principle is not correct.
Morpho Towers, Two Standing Spirals - Dec 1, 2011
This YouTube video, "Morpho Towers, Two Standing Spirals," by Sachiko Kodama, shows a ferrofluid work of art. You can see the video at Morpho Towers, Two Standing Spirals, and learn more about it by visiting this webpage.
Particles break light-speed limit - Nov 1, 2011
You may have heard the shocking news that a careful experiment at an Italian laboratory found the speed of a neutrino beam to be slightly greater than the speed of light. This directly violates special relativity, which predicts that no particle can move faster than the speed of light (please note that the "speed of light" referred to here is the speed of light in a vacuum). To learn more about this experimental result, see Particles break light-speed limit. And for a theoretical argument why faster-than-light neutrinos are impossible, visit this Scientific American Blog.
Aircraft Contrails - Oct 1, 2011
Visit Aircraft Contrails from NASA for more information on how contrails can cause global warming. For more from NASA, see Clouds Caused by Aircraft Exhaust May Warm the US Climate.
Einstein's Relativity and Everyday Life - Sep 1, 2011
If you rely on a GPS to navigate, then you need Einstein's theories of relativity--special relativity because the GPS satellites are moving fast relative to you, and general relativity because the GPS satellites are in a different gravitational field than you are. Without correction for relativistic effects, errors in GPS positions would increase by 10 km for every day the system operates! To learn more visit Einstein's Relativity and Everyday Life, and also this Ohio State astronomy page.