GED Info

Electricity happens because electrons move through substances. An electron is a stable subatomic particle in the lepton family having a rest mass of 9.1066 × 10-28 grams and a unit negative electric charge of approximately 1.602 × 10-19 coulombs.

Electronics is the study of the behavior of electricity in vacuum tubes and semiconductors. This study has made possible many of the inventions of the Twentieth Century - the radio, radar, cell phone, and computers.

Which of the following Twentieth Century communication inventions requires a knowledge of electronics?
(1) watch
(2) phonograph
(3) telephone
(4) telegraph
(5) None of the above