题干

宇航员乘飞船前往A星球,其中有一项任务是测该星球的密度。已知该星球的半径为R,引力常量为G。结合已知量有同学为宇航员设计了以下几种测量方案。你认为不正确的是(      )

A:当飞船绕星球在任意高度运行时测出飞船的运行周期T。

B:当飞船绕星球在任意高度运行时测出飞船的运行周期T和飞船到星球的距离h。

C:当飞船绕星球表面运行时测出飞船的运行周期T。

D:当飞船着陆后宇航员测出该星球表面的重力加速度g。

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答案(点此获取答案解析)

A

同类题2

阅读理解

    I was wandering around the Albuquerque International Sunport Airport. My flight had been delayed and I heard an announcement: “If anyone near Gate A – 4 understands Arabic(阿拉伯语),please come to the gate immediately. ” Gate A – 4 was my own gate. I went there.

    An older woman was crumpled (蜷缩成一团的) on the floor, she reminded me of my grandmother.

    “Talk to her,” urged the flight agent. “We told her the flight was going to be late, and she did this.”

    I bent over to put my arm around the woman and spoke uncertainly. “Shu-dow-a, shu-bid-uck, habibti? She stopped crying. She thought the flight had been canceled. She needed to be in El Paso for a medical treatment the next day. I said, “You'll get there, just late. Who is picking you up? Let's call him.”

    We called her son. In English, I told him that I would stay with his mother until we got on the plane. She talked with him. Then we called her other sons just for fun. Then we called my dad, and they spoke for a while in Arabic and found out that they had several shared friends. After that, I called some Palestinian poets I know and let them chat with her.

    She was laughing a lot by then, patting my knee and answering questions. She pulled a bag of home-made cookies filled with nuts and topped with sugar from her bag and offered them to the women at the gate. To my amazement, no one refused. It was like a sacrament (圣餐). The traveler from Argentina, the mom from California, the lovely woman from Laredo —we were all smiling, covered with the same sugar.

    I looked around that gate and thought: This is the world I want to live in, one with no anxiety. This can still happen anywhere, I thought. Not everything is lost.