intensity vs strength

intensity

noun
  • The degree of strength. 

  • Time-averaged energy flux (the ratio of average power to the area through which the power "flows"); irradiance. 

  • Can mean any of radiant intensity, luminous intensity or irradiance. 

  • Synonym of radiance. 

  • The quality of being intense. 

  • The severity of an earthquake in terms of its effects on the earth's surface, and buildings. The value depends on the distance from the epicentre, and is not to be confused with the magnitude. 

strength

noun
  • The quality or degree of being strong. 

  • The intensity of a force or power; potency. 

  • The strongest part of something; that on which confidence or reliance is based. 

  • A positive attribute. 

How often have the words intensity and strength occurred in a corpus of books? (source: Google Ngram Viewer )