Nick Hiebert, a 23 year old male from the Internet asks on November 14, 1999,Is there a substance known to science that reacts to electrical impulses by contracting or changing its density?
viewed 13740 times
There may be many such things. One thing I'm aware of are piezoelectric materials that do this: salts, ceramics, and plastics. The chief polymer used for this is Polyvinylidene Fluoride (PVDF). If you do web searches on this, you will find much info. A good explanation can be found at http://www.ndt.net/article/yosi/yosi.htm
Note: All submissions are moderated prior to posting.
If you found this answer useful, please consider making a small donation to science.ca.