image credit: R.J. Celotta, S. Balakirsky, J.A. Stroscio/NIST; image source; larger image
This scanning tunneling microscope (STM) image shows a "corral" for electrons that was created on a crystal surface. To find out how how these images are made, visit The Scanning Tunneling Microscope. For an artistic gallery of similar images, see IBM: STM Gallery.
(This feature was updated on March 23, 2012.)
Standing Waves: Harmonics and Patterns
To find out how two running waves in a tube add up to a standing wave, visit this Penn State animation. For a tutorial on standing waves, with animations, visit Standing Waves: Harmonics and Patterns.
(This feature was updated on March 21, 2012.)