题干

操场上有三根测杆AB,MN和XY,MN=XY,其中测杆AB在太阳光下某一时刻的影子为BC(如图中粗线).

(1)画出测杆MN在同一时刻的影子NP(用粗线表示),并简述画法;

(2)若在同一时刻测杆XY的影子的顶端恰好落在点B处,画出测杆XY所在的位置(用实线表示),并简述画法.

 

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答案(点此获取答案解析)

解:(1)连接AC,过点M作MP∥AC交NC与P,

则NP为MN的影子;

(2)过B作BX∥AC,且BX=MP,过X作XY⊥NC交NC与Y,

则XY即为所求.

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