This change in polarity causes the magnetic field in front of the train to pull the vehicle forward, while the magnetic field behind the train adds more forward thrust.

这种极性的变化导致列车前方牵引列车前进的电磁场，同时列车后面的电磁场加上了更多的向前推力。

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The polarity of impulse voltage and the polarity of insulator surface electric charge can affect the corona initial time of insulator, the change time - interval and the corona current.

外拖冲击电压的极性与绝缘子表面电荷极性是否相同会影响绝缘子的电晕起始时刻、由流注向先导的转变时间间隔和流注电晕电流。

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The electric current supplied to the coils in the guideway walls is constantly alternating to change the polarity of the magnetized coils.

供给导轨槽内线圈的电流交互变化着电磁线圈的极性。

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To change from a one to a zero, the microprocessor sends electrical currents to change the polarity of the top layer.

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Reality extends to the plain fact that there is no switch or level to push, pull or toggle that will instantaneously change the polarity of the flow.

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To change the bit from a one to a zero to write or store new data the microprocessor sends electrical currents through the chip to change the polarity of the top layer.

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