问题 计算题

某行星探测器在其发动机牵引力作用下从所探测的行星表面竖直升空后,某时刻速度达到v0=80m/s,此时发动机突然发生故障而关闭,已知该行星的半径为R=5000km、第一宇宙速度是v=5km/s。该行星表面没有大气,不考虑探测器总质量的变化及重力加速度随高度的变化。求:发动机关闭后探测器还能上升的最大高度。

答案

在该行星表面                  (4分)

设该行星的第一宇宙速度为                            (4分)

      (4分)

则探测器能上升的最大高度为                             (4分)

单项选择题 A1型题
完形填空

阅读下面短文, 并根据短文后的要求答题(请注意问题后的字数要求)。

【1】 One day, a poor boy who was trying to pay his way through school by selling goods door to door found that he only had one dime(10分硬币)left. He was hungry so he decided to beg for a meal at the next house.

【2】 However, he lost his courage when a lovely young woman opened the door. Instead of a meal he asked for a drink of water. She thought he looked hungry so she brought him a large glass of milk. He drank it slowly, and then asked, “How much do I owe you?”

【3】 “You don’t owe me anything,” she replied. “Mother has taught me never to accept pay for a kindness. ” He said, “Then I thank you from the bottom of my heart.” As Howard Kelly left that house, he not only felt stronger physically, but it also increased his faith in God and the human race. He was about to give up and quit before this point.

【4】Years later the young woman became critically ill. The local doctors were baffled. They finally sent her to the big city, where specialists can be called in to study her rare disease. Dr Howard Kelly, now famous, was called in for the consultation. When he heard the name of the town __________, a strange light filled his eyes. Immediately, he rose and went down through the hospital hall into her room.

【5】Dressed in his doctor’s gown he went in to see her. He recognized her at once. He went back to the consultation room and determined to do his best to save her life. From that day on, he gave special attention to her case.

【6】After a long struggle, the battle was won. Dr Kelly requested the business office to pass the final bill to him for approval. He looked at it and then wrote something on the side. The bill was sent to her room. She was afraid to open it because she was positive that it would take the rest of her life to pay it off. Finally she looked, and the note on the side of the bill caught her attention. She read these words…

“Paid in full with a glass of milk”

(Signed) Dr Howard Kelly

【7】Tears of joy flooded her eyes as she prayed silently, “Thank you, God. Your love has spread through human hearts and hands. ”

小题1:What is the best title of the passage? (No more than 8 words. )

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小题2:When Dr. Howard Kelly heard the name of the town, what did he do?

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小题3:Please fill in the blank in the fourth paragraph with proper words or phrases to complete the sentence.

(No more than 5 words. )

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小题4:When the young woman read the note, what was her feeling? (No more than 4 words. )

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小题5:What does the underlined word “it” (Sentence3, Paragraph 6) refer to?

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