Subscribe
Subscribe
MY AMERICAN SCIENTIST
LOG IN! REGISTER!
SEARCH
 
Logo IMG
HOME > My Amsci > Restricted Access

Good Vibrations



Restricted Access The content you've requested is available without charge only to active Sigma Xi members and American Scientist subscribers.


If you are an active member or an individual subscriber, please log in now in order to access this article.

If you are not a member or individual subscriber, you can:



Abstract:

A vibrating system has a characteristic spectrum, a set of frequencies at which the system gives a large response. For instance, a washing machine with an unbalanced load will only get seriously out of whack at certain rates of oscillation. At these natural frequencies the system exhibits special characteristics, including nodes (on a vibrating string, for instance) and nodal lines (seen as areas where sand collects on a vibrating plate) where there is no oscillation. It turns out that one can measure Doppler shifts at these lines and then apply simple mathematical formulas to learn much about the physical properties of the vibrating system. The author has developed just such formulas for vibrating membranes and discusses such interesting applications as the design of turbines.


Subscribe to American Scientist