试题与答案

(6分)如图所示,左图为“嫦娥一号”卫星发射,火箭升空时的照片。右图为“嫦娥一号

题型:问答题

题目:

(6分)如图所示,左图为“嫦娥一号”卫星发射,火箭升空时的照片。右图为“嫦娥一号”卫星的运行路线图。 

   

(1)运载火箭将“嫦娥一号”平地托起,直冲云天。火箭在加速上升过程中,机械能            (填“增大”、“减小”或“不变”),它是利用向后喷出气流而使自身受力前进的,这是运用了力学中                     的规律。

(2)卫星运载火箭在飞行中,地面的指令是通过         发送给火箭的. (填“超声波”或“电磁波”),当火箭离地300 km时,地面发出的指令经过         秒可传送到火箭

(3)“嫦娥一号”卫星发射后,首先将被送入一个椭圆轨道,这一轨道离地面最近距离为500km,最远为7×104 km,从远地点到近地点运行的过程中,飞船的速度将             ,势能将            。(填“变大”、“变小”或“不变”).

答案:

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参考答案:D解析:该患者诊断为重症肌无力,发生重症肌无力危象应用人工呼吸器辅助呼吸,保持呼吸道通畅是关键。

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