A time interval equal to 1/根号360 of the time required for one complete cycle of alternating current.Mechanical rotation
is often measured in degrees.360° constituting one complete revolution. In describing alteruating voltages and
currents,the time for one one complete cycle isconsidered to be equivalent to 360 electrical degrees（360°）or 2π
electrical radians 。 for example，if the frequency f is 60 cycles per second（60HZ），360°corresponds to 1/根号60 second
and 1 electrical degree to 1/根号21600 second。
谢谢http://zhidao.baidu.com/question/91884010.html
is often measured in degrees.360° constituting one complete revolution. In describing alteruating voltages and
currents,the time for one one complete cycle isconsidered to be equivalent to 360 electrical degrees（360°）or 2π
electrical radians 。 for example，if the frequency f is 60 cycles per second（60HZ），360°corresponds to 1/根号60 second
and 1 electrical degree to 1/根号21600 second。
谢谢http://zhidao.baidu.com/question/91884010.html
