power strip vs trip cord

power strip

noun
  • A block of electrical sockets that attaches to the end of a flexible cable and allows multiple electrical devices to be plugged in. 

trip cord

noun
  • A cord, line, lanyard, or wire that, when pulled, mechanically activates a device. 

  • A type of electrical extension cord: see pad. 

How often have the words power strip and trip cord occurred in a corpus of books? (source: Google Ngram Viewer )