The rockets take astronauts and man-made satellites into space. The satellites are used for communication, weather monitoring and research. But how do satellites stay up without Falling down?There are 题目和参考答案——青夏教育精英家教网—

题目内容

The rockets take astronauts and man-made satellites into space. The satellites are used for communication, weather monitoring and research. But how do satellites stay up without Falling down?

There are two opposite forces acting on the satellite. One of them is the force of gravitation(地心引力), which tries to pull the satellite toward the earth. The other force is created by the rotation (旋转)of the satellite around the earth. This force tries to take the satellite away from the earth. With these two forces, the satellite goes round and round. The gravitational pull of the earth is like a rope which keeps the satellite from flying away.

Everything that goes up has to come down. It is only a matter of time before a satellite comes back to the earth. As time goes by, the satellite loses its speed, which makes the gravitational pull stronger than the force pulling it away. This makes the satellite crash (坠落)down to the earth.

1.The force that pulls the satellite towards the earth is created by ________.

A. the earth B. the satellite itself

C. the rotation of the satellite D. the rope

2.Why can't the satellites fly away?

A. Because of the force from the earth.

B. Because the satellite is too big.

C. Because of the force created by the rotation of the satellite around the earth.

D. Because people on earth have made ropes to tie the satellites tightly.

3.Which of the following is TRUE according to the passage?

A. There are four forces acting on the satellite.

B. The force of gravitation makes the satellite go round and round.

C. As time goes by, the satellite will finally fall down.

D. The satellite will stay in space forever.

练习册系列答案

相关题目

阅读下面短文，根据短文内容，完成下面表格，每空不超过4个单词。

Sometimes it may seem difficult to improve our health. If so, the following health habits may help you.

Eat breakfast every morning

Research(研究) shows that if you eat a meal in the morning, you may not become too fat or eat too much during lunch. Eating breakfast can help people feel better through the day.

Get enough sleep

Poor sleep can influence (影响) our memory and learning. It can also cause traffic accidents! Studies show that people who don’t get enough sleep seem to get into more accidents. So stay safe and get enough sleep!

Take a walk every day

Walking is an easy way of exercising. You’d better meet friends for a walk, not for a meal. As you walk, you will see the beautiful world around you. Once you try, you’ll find that adding a walk into your daily life is very easy.

Join social groups

Social groups can provide support. They might include sport teams, art or music groups. The people in the group can offer advice and can help each other in difficult times. Also, being in a group keeps your mind busy. And active mind is a healthy mind.

Have a hobby

A hobby could be running, reading or making something with your hands. Hobbies help people to relax and rest. Hobbies bring us joy, too.

Ways to improve our health
Eat breakfast every morning	◆It can help you feel better1..
Get enough sleep	◆Poor sleep 2. and learning.
Take a walk every day	◆Enjoy the 3. while walking.
Join social groups	◆Being in a group keeps your 4..
Have a hobby	◆Hobbies 5.as well.

Do you like go running? Some people think running is boring. But there are ways to make it more exciting – for example, “plogging”.

Plogging is a new exercise trend（趋势）from Sweden. The name comes from the words “pick up” and “jogging”. It means picking up trash（垃圾）while running.

Ploggers go outside with a pair of gloves and a trash bag. They stop to pick up trash as they run. Nobody likes to see trash while they’re doing exercise. This new trend brings environmental protection (环境保护) and healthy living together.

Plogging may even be better for you than just running, since bending down (弯腰) to pick up trash is another kind of exercise itself. So try plogging with your friends on your way to school. You can stay healthy and keep the environment clean at the same time.

1.What trend does this story talk about?

A. Making new words. B. Running with gloves.

C. Picking up trash while running. D. Throwing away trash in bags.

2.Where did the trend come from?

A. Switzerland. B. The United States. C. Sweden. D. Spain.

3.What is the best part of this new trend?

A. More people are wearing gloves while running.

B. Runners take their own bags, so there will be no trash.

C. It tells people to stop using public trash bags.

D. It’s good for the environment and people’s health.

4.The last paragraph (节) mainly tells us that _________.

A. bending down while plogging is also good exercise.

B. it is not important to keep the environment clean.

C. plogging gives you a chance to make friends.

D. you should run to school with your friends.

5.Which of the following is TRUE?

A. All people think running is boring.

B. Ploggers go out with only a pair of gloves.

C. Maybe plogging is better than running.

D. Plogging is the best sport.

— Hello, who’s that speaking?

— .

A. This is Jim speaking B. I’m Mike C. That’s Jane D. She is Nancy

请认真阅读下面短文并用英语回答问题，将答案写在横线上。

Mother Teresa once said, "Every time you smile at someone, it is an action of love, a gift to that person" However, a recent survey showed that 25% of Chinese never smiled or smiled less than five times a day. It also found that 2~6 of Chinese were willing to smile at strangers.

To make a change, forty students from Shanghai Normal University started a team of "Smiling Volunteers". Their first smiling task was-to smile at all the visitors in the Shanghai Film Art Centre and ask if they needed their help. Not all students found it easy to smile all the time. "When volunteers help other people, smiling is the best way to make them understand that volunteers are ready and sincere(诚挚的),”one team leader said.

A teacher in charge of(负责)the team thought the team's work was not all fun and games. "Most of our students will be teachers after they leave university. Smiling is necessary for good teachers. We hope they can learn how to smile at each other, she said. Everyone smiles in the same language. So it's not important whether you are a teacher or not. After all, sincere smiling and helping hearts are the most important. If today you don't start a day with a smile, it won't be too late to start practising for tomorrow. Remember "The world always looks brighter from behind a smile."

1.How many Chinese never smiled or smiled less than five times a day?

2.What will most of the students be after they leave Shanghai Normal University?

3.Do you think smiling is necessary in your life? Why or why not?

一Could you tell me how to behave politely in public in the UK?

一Yes. ，you should keep your voice down and always queue.

A. After all B. First of all

C. In all D. At all

he with his classmates basketball next week?

A. Are; going to play B. Do; play

C. Is; play D. Is; going to play

Pawnshop(典当行)are not malls. You can borrow some money at pawnshops if you leave something as a pledge. You can also take back what you left if you return enough money on time. But if you can’t, the owner of the pawnshop will sell your things. Pawnshops may be large or small, but they are all full of different things.

Few people want to go to the pawnshop unless they need much money. But sometimes people do want to sell things. Most pawnshops accept many kinds of things,including jewelry(珠宝),watches, clothes and so on. So the owners of the pawnshops must know a lot. Because some things may have been kept in a family for many years, the owners of the shops have to tell how old they are,whether they are real or how much they are worth. The owner of the pawnshop might buy it at a low price and then try to sell it for a higher price. About 25% to 35% of their money comes from selling things.

1.What should you do if you want to borrow some money at a pawnshop?

A. Have a good job B. bring your ID(身份证)there

C. Know the owner very well D. leave something at the pawnshops

2.The owner of the pawnshop will sell your things if_________

A. The pawnshop is full of different kinds of things

B. The owner of the pawnshop earn some money by selling things

C. You can’t return the money that you borrowed on time

D. The pawnshop needs much money to buy other things.

3.Which of the following is true according to the passage?

A. Nobody wants to sell something at the pawnshops

B. The owner of the pawnshop make some money by selling things

C. The pawnshop will keep things for us as long as possible.

D. Most pawnshops only accept jewelry.

4.What’s the meaning of the underlined word “pledge”in Chinese?

A. 慈善 B. 机会 C. 欠款 D. 抵押

5.What’s the main idea of the passage?

A. Different kinds of pawnshops B. The owner of the pawnshops

C. Many kinds of things in the pawnshop D. Some introductions of the pawnshops

试题分类