教材中对右手螺旋定则的叙述是这样的:“用右手握住螺线管,让四指弯曲且跟螺线管中电流的方向一致,则大拇指所指的那端就是螺线管的N极.”这一定则阐明了电流方向(此即电流的环绕方向)与螺线管极性二者之间的关系.应用这一定则,如果知道电流的环绕方向,就可判断螺线管的极性;相反,知道螺线管极 The narrative of the right-handed spiral rule in the textbook is this: “Hold the solenoid with your right hand so that the four fingers bend and follow the direction of the current in the solenoid. Then the end of the thumb is the solenoid. N-pole.” This must clarify the relationship between the direction of the current (this is the current’s direction of encirclement) and the polarity of the solenoid. Applying this must, if you know the direction of the current, you can determine the solenoid. Polarity; on the contrary, knowing the solenoid pole