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一架在静止空气中以每小时180公里的速度向正北飞行的飞机,30分钟后被发现偏离预定航线约80公里,偏移方向为北偏东约5度。这种偏离表明侧风影响了飞机的预定航迹。实际的地面路径呈对角线,说明由于风的影响,飞机相对于地面的有效速度降低至每小时160公里,并略微偏向东方。
通过分析偏离预定路径的位移,推断出…
一架飞机以每小时180公里的恒定空速向正北方向飞行。30分钟后,发现其位置距离起点80公里,但偏北偏东5度。这表明风改变了飞机的预定航迹。
目标是求出风速以及飞机为保持预定航向应飞行的方向。
飞机的对地速度由其预期速度与风速合成,形成一个矢量三角形。
该飞机在30分钟内飞行了80公里,由此可得其地速的大小。由于该速度方向为北偏东5度,因此可分解为两个分量:向北分量和向东分量。
目标速度为正北方向,每小时180公里。从地速中减去该速度可得到风速。其大小通过勾股定理求得。
最后,为了保持航向,飞行员必须略微向西偏北方向飞行,以抵消风的影响。
通过将调整后的速度分解为分量,并使向西的分量与风的向东推力相平衡,可得出该调整值。结果表明,飞机必须向北偏西约 4.4 度方向飞行,才能保持预定航向。
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Q1: How does wind affect a plane's ground velocity and actual path?
Wind combines with the plane's intended velocity to create ground velocity, the actual path traveled. A plane flying north at 180 km/h with a crosswind will deviate from its intended course. The ground velocity results from vector addition of the plane's airspeed and wind velocity, forming a vector triangle. This combined motion determines both the plane's actual speed and direction relative to the ground.
Q2: What is the relationship between displacement, ground velocity, and wind velocity?
Ground velocity equals the plane's intended velocity plus wind velocity. When a plane travels 80 kilometers in 30 minutes while aiming north, this displacement reveals the combined effect of both velocities. By subtracting the intended velocity from the ground velocity, you isolate the wind's contribution. This vector subtraction reveals wind magnitude and direction, essential for understanding navigation errors.
Q3: How do you calculate wind velocity magnitude using the Pythagorean Theorem?
Wind velocity is found by resolving ground velocity into components and subtracting the intended velocity. The northward and eastward components of ground velocity are separated, then the northward intended velocity is subtracted from the northward component. The remaining northward and eastward components form a right triangle, where the wind velocity magnitude equals the hypotenuse calculated using the Pythagorean Theorem.
Q4: Why must a pilot adjust heading west of north to maintain a northward course?
The wind pushes the plane eastward, so the pilot must aim west of north to counteract this drift. By introducing a westward velocity component, the plane's adjusted heading cancels the wind's eastward influence. A 4.4-degree westward adjustment creates a resultant velocity pointing due north, ensuring the plane follows its intended path despite wind interference.
Q5: What does resolving velocity into components reveal about wind direction?
Resolving velocity into northward and eastward components isolates wind's directional effect. Ground velocity components show the plane traveled mostly north but also eastward, revealing wind's eastward push. By comparing intended and actual velocity components, the wind's magnitude and direction become clear. This component analysis demonstrates how wind introduces both speed reduction and directional deviation.
Q6: How does vector addition explain the plane's 80-kilometer displacement in 30 minutes?
The plane's ground displacement results from adding its airspeed vector to the wind velocity vector. Flying north at 180 km/h for 30 minutes would cover 90 kilometers, but wind deflects the path eastward, reducing ground speed to 160 km/h and creating an 80-kilometer displacement. This vector sum demonstrates how two velocity vectors combine to produce the actual path traveled.
Q7: What is the estimated magnitude of the wind velocity in this navigation problem?
The wind velocity magnitude is approximately 24.9 kilometers per hour, acting consistently throughout the 30-minute flight. This wind speed was calculated by analyzing the difference between the plane's intended northward path and its actual ground displacement. The wind's eastward component caused the 5-degree deviation, demonstrating how relatively modest wind speeds significantly alter aircraft trajectories.