Silicon Valley star Thomas Middleditch is engaged to his girlfriend Mollie Gates, Us Weekly can exclusively confirm. PHOTOS: Celebrity weddings 2015.
Why, Alternating Current and Direct Current, of course! Both AC and DC describe types of current flow in a circuit. In direct current (DC), the electric charge (current) only flows in one direction. Electric charge in alternating current (AC), on the other hand, changes direction periodically. The voltage in AC circuits also periodically reverses because the current changes direction.
Electric power distribution requires a circuit, usually represented as two wires leading to a device that uses electricity. In AC current, one wire is negative and the other is either is positive or neutral (ground). The two wires take turns at sending electricity. In North America, AC current uses a standard rhythm in which each side gets its turn 60 times each second, thus the 60Hz designation given to standard AC current.