也称“惯性参照系”。能使牛顿第一运动定律成立的，匀速直线运动的，用简单形式描述运动的参考系inertial frame of reference

• “牛顿运动定律及其应用”考点的说明“在非惯性系内处理运动的问题不作要求”。

  The explanation of the "Newton's Laws of Motion and their applications" examination point says that "there are no requirements for questions about handling motion in a non-inertial frame of reference"

• 测地线效应与惯性系拖曳效应获实验证实。

  Geodetic procession and frame-dragging effects have been proven in experiments.