印度的月球卫星“月船1号”已失联八年，地面测控中心通过计算预测“月船1号”会经过月球北端上空165km高处的A点，便在某时刻向该处发射_1（电磁波/超声波）信号，2.6s后收到回波信号，从而确信“月船_刷题宝

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印度的月球卫星“月船1号”已失联八年，地面测控中心通过计算预测“月船1号”会经过月球北端上空165km高处的A点，便在某时刻向该处发射____（电磁波/超声波）信号，2.6s后收到回波信号，从而确信“月船1号”依然在轨道运行，测控中心距离A点____ km.（v_电磁波=3×10⁸m/s,v_声=340m/s）

上一题下一题 0.0难度选择题更新时间:2020-03-31 01:33:55

答案(点此获取答案解析）

电磁波,3.9×10⁵

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