AC vs electromagneticism

AC

phrase
  • as charged, as in: guilty as charged, usually a/c. 

noun
  • Companion of the Order of Australia. 

name
  • Aceh, an autonomous province of Indonesia. 

  • Acre, a state of Brazil. 

electromagneticism

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