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According to well-known electrodynamic laws, an electron moving in a magnetic field is acted upon by a force which runs perpendicular to the direction of motion of the electron and to the direction of the magnetic field, and whose magnitude is easily determined.
根据众所周知的电动学定律，在磁场中运动的电子受到垂直于电子运动方向和磁场方向的力的作用，其大小很容易确定。