The root mean square (rms) is the square root of the average of the squares of a series of related values. In the context of alternating current, the rms value corresponds to the direct-current value that would generate an equivalent heating effect. For a sine wave, the rms value is 0.707 times the peak value. In the absence of specific specifications, alternating quantities are generally assumed to be expressed in rms values. The rms value is also referred to as the effective value.