题目身高为h的人,沿平直路面远离路灯而去,已知路灯高为H.试判断(1)当人匀速远离路灯时,人影端点的运动性质;(2)当人匀加速远离路灯时,人影端点的运动性质.解:(1)设人从路灯正下方开始运动,经时间t时人影长为l1,2t时人影长为l2,人的运动速度为v The subject height h is away from the street lamp along a straight road surface. The known street light is H. Try to determine (1) the nature of the movement of the silhouette endpoint when the person moves away from the street light at a constant speed; (2) when the human speed accelerates away from the street light At the time, the nature of the movement of the silhouette endpoints. Solution: (1) Let the person start the movement from just below the streetlight. At time t, the length of the figure is l1, and when the figure is 2t, the length of the figure is l2. The speed of the person’s movement is v.