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一、前言“升力”一词容易造成错觉,以为这种力总是朝上的,实际并非如此。升力总是与运动或流体(产生于任何方向)的方向成直角。当手伸出行进的车窗时,改变手形和倾斜度则能感受到升力。水的密度比空气大得多,所以当手在水中慢划时会感受到同样的升力。二、升力理论分析与气流(水流)方向有关的倾斜方向称为迎角。逐渐增大迎角会产生更大的升力。随着升力的增加,与运动方向相反的阻力也会增加。升力增加到一定限度时升力显著下降而阻力仍很大。游泳中臂的动作不能整个归为升力推进或阻力推进,两种推进方法对推进合力都有影响。
I. INTRODUCTION The word “lift” tends to create an illusion that this force is always upward, but it is not. Lift is always at right angles to the direction of movement or fluid (generated in any direction). When the hand stretched out the traveling window, you can feel the lift by changing the hand and the inclination. The density of water is much greater than the air, so the same lift is felt when the hand is slowly drowned in the water. Second, the lift theory analysis and airflow (water flow) direction of the tilt direction is called the angle of attack. Gradually increasing the angle of attack will produce greater lift. As the lift increases, the resistance that moves in the opposite direction increases. Lift increased to a certain extent, a significant drop in lift and resistance is still great. The action of swimming in the arm can not be attributed to the promotion of lift or resistance to promote the two methods of propulsion have an impact on the promotion together.