Encyclopedic Dictionary of Polymers

2011 Edition
| Editors: Jan W. Gooch

Logarithmic Decrement

  • Jan W. Gooch
Reference work entry
DOI: https://doi.org/10.1007/978-1-4419-6247-8_7000
\ ló-gә- ri th-mik de-krә-mәnt\ (Δ) In a damped, vibrating system, the natural logarithm of the ratio of the amplitude of any oscillation to the amplitude of the succeeding oscillation. Where damping is mild, the ratio of the amplitude of any oscillation to the amplitude of the succeeding oscillation. Where damping is mild, the ratio of amplitudes several vibrations apart will usually give a more accurate estimate. The equations are:
$$ \Delta {\rm\ = ln(}A_i /A_{i{\rm + 1}} {\rm )\ and }\ \Delta {\rm\ =(l/n) {\cdot} ln(}A_i /A_{i{\rm + n}} {\rm )}$$
This is a preview of subscription content, log in to check access.

Copyright information

© Springer Science+Business Media, LLC 2011

Authors and Affiliations

  • Jan W. Gooch
    • 1
  1. 1.AtlantaUSA