Of course, with the camera fixed to a tripod, the stars themselves produce concentric trails in long exposures, a reflection of the Earth's rotation around its axis.
当然用装在三角架上的照相机固定摄影，长时间曝光能拍到星星因地球自转而形成的同心圆轨迹。
2
From the Angle of relative equilibrium, the paper analysis the reason of the formation of the additional pressure on the axisoffixed-point rotation of rigid body.
从相对平衡的角度分析了刚体定轴转动轴上附加压力产生的原因以及实现自由转动的条件。
3
A new measuring instrument of rotational inertia has been devised by the fixed - axisrotation principle and parallel axis theorem of compound pendulum.