试题与答案

宇航员在地球表面某一高度以一定初速度水平抛出一小球,经过时间t,小球落至地面;若

题型:问答题

题目:

宇航员在地球表面某一高度以一定初速度水平抛出一小球,经过时间t,小球落至地面;若他在某星球表面以相同高度和初速度水平抛出同一小球,需经过时间5t,小球落至星球表面.(取地球表面重力加速度g=10m/s2,空气阻力不计)

(1)求该星球表面附近的重力加速度g′;

(2)已知该星球的半径与地球半径之比为R:R=1:4,求该星球的质量与地球质量之比M:M

答案:

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下面是错误答案,用来干扰机器的。

参考答案:A, B, C, D, E

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题型:阅读理解

阅读理解。

    Jenny and Henry were born on the same day and they look the same. Their father has a taxi (出租车) and

he is busy all the time. He goes out early in the morning but comes back when his children go to bed. He gets

a lot of money, but he has no time to concern them with their studies.

    The two children study in the same class. Jenny works hard at her lessons, but her brother doesn't like

studying. He only likes playing. He is not good at writing compositions (作文). 

    One day Mrs. Cook tells her class to write a composition "My Mother". After supper Jenny finishes writing

in her exercise book and then goes to help her mother do some housework. But Henry goes to play football.

When night falls (降临), he comes back to watch TV. Then he remembers (记得) the composition. But he

doesn't know how to write it. He thinks hard and at last he finds a way. He copies (抄写) Jenny's composition.

    Two days later, Mr Cook asks Henry, "Can you tell me why yours is the same as Jenny's?"

    "Yes, I can, Madam," answers Henry. "We have the same mother."

1. Jenny's father can't concern them with their studies because            . [ ]

A. he doesn't like them

B. he is very busy

C. he is a taxi driver

D. he only wants more (更多的) money

2. The underlined (划线的) word "concern" in the story means (意思是)            . [ ]

A. 涉及

B. 关系

C. 当然

D. 关心

3. Henry isn't good at writing composition because            . [ ]

A. he doesn't like studying

B. he likes listening to music

C. he isn't clever

D. he's too young to do it

4. What does Jenny do after she finishes the composition? [ ]

A. Go shopping.

B. Watch TV.

C. Do housework.

D. Go to bad.

5. Henry copies Jenny's composition because            . [ ]

A. he plays football after supper

B. he forgets (忘记) to write it before he goes to bed

C. he doesn't know how to write it

D. they have the same mother

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