The Gruen zones is a system of dividing the interface between the femoral component of a hip arthroplasty and the femur bone moving from lateral to medial calcar, when viewing an AP radiograph of the hip, clinically useful to record the appearance of lucent areas when assessing the outcome of the operation.
This article is about the band. For other uses, see AC/DC (disambiguation). AC/DC are an Australian rock band, formed in 1973 by brothers Malcolm and Angus Young. A hard rock/blues rock band, they have also been considered a heavy metal band, although they have always dubbed their music simply rock and roll.
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.