impairment vs voltage

impairment

noun
  • A deterioration or weakening 

  • The result of being impaired 

  • A downward revaluation, a write-down. 

  • A disability or handicap 

  • an inefficient part or factor. 

voltage

noun
  • The difference in electrostatic potential between two points in space, especially between live and neutral conductors or the earth. 

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