Have you ever rubbed your hands together when they get cold? Why do we do that? We do that for friction. Friction happens when two things that aren't very smooth rub together to make heat energy. The faster you rub two things together, the more friction (and heat) you can make. Let's discover friction!
WHAT YOU'LL NEED:
● Soap ● Water ● Your hands!
WHAT TO DO:
①Make sure your hands are dirty.
②Rub your hands together until you feel the heat of your hands.
③Now, use soap and water to get your hands very slippery(滑的).
④Try to make friction happen while your hands are slippery.
⑤Please write down what has happened.
LET'S TALK!
Friction is an energy that happens when two things tub together. When friction happens, it makes heat! When your hands are slippery, they won't make very much friction and your hands won't get so hot.
DID YOU KNOW?
● Friction happens when you stop your fast running bike.
● Ancient people made fires by rubbing two pieces of wood together. Friction happened though they didn't know it.
Friction is everywhere. Have you ever noticed situations where friction is happening? If not, ask your parents to take you out in a car. If it is not hot, touch the tires(轮胎) of the car before and after a short drive to see how much warmer they get from friction.
1.This text is most probably .
A.a science report B.a car advertisement
C.a rubbing introduction D.a chemistry programme
2.You'd better make your hands to get heat when you rub them.
A.slippery B.dry C.wet D.smooth
3.What does the word "friction" in this text mean in Chinese?
A.摩擦 B.冷却 C.膨胀 D.震动
4. is not an example of friction.
A.Bike riding B.Car driving
C.Hands rubbing D.Friction discovering
5.What's the last column(栏目)?
A.THINK IT OVER! B.WHAT HAPPENED?
C.EVERYDAY ACTION D.WORK WITH PARENTS
一本好题口算题卡系列答案科目：初中英语 来源：山东省东营市广饶县（人教版五四学制）2019-2020学年六年级上学期期末英语试卷 题型：单选题
My shoes ____ old. I want to buy a new ______.
A.is; one B.are; one C.is; pair D.are; pair
查看答案和解析>>
科目：初中英语 来源：2019年河南省郑州市中考四模英语试卷 题型：单选题
— Has Tom returned _____dictionary to you?
—No, he gave me _____empty promise.
A.the; an B.a; an C.the; the D.a; the
查看答案和解析>>
科目：初中英语 来源：浙江省台州市温岭市2019-2020学年八年级上学期期末英语试卷 题型：信息匹配
阅读下列材料, 从所给的七个选项(A、B、C、D、E、F 和 G)中,选出最符合各段落的小标题。选项中有两项是多余选项。
A. Sleep well. B. Take notes. C. Read books. D. Make a plan E. Ask for help F. Think twice. G. Pay attention.
Do you want to get good grades? The following advice may help you to get a better one.
1.
You’d better make sure you’re sitting in a proper seat so that you can pay attention to your teachers. Tell your teachers or parents about any problem that is bad for your attention in class
2.
Try to write down what your teacher says or writes on the blackboard. It's best to write in a neat way so that you can read your totes later.
3.
It is not a good habit to put off what you can do today till tomorrow. It’s bad for your study. In fact, the best way to study is to plan ahead.
4.
If you don’t know how to solve the problems at school, you can ask your teacher for help. If you’re at home, our parents might help you.
5.
If you have a test tomorrow, but suddenly you can’t remember anything, not even 2+2, don’t worry. Try to get a good night’s sleep and you’ll be surprised at what comes back to you in the morning.
查看答案和解析>>
科目：初中英语 来源：浙江省台州市温岭市2019-2020学年八年级上学期期末英语试卷 题型：完型填空
A long time ago, there was a very big tree. A little boy loved to come and play around it _______ He loved the tree and the tree loved to play with him. Time went by. The little boy had grown up and he no longer (不在) played around the tree. One day, the boy came back and the tree was so_________“Come and play with me!”the tree said. “ I don’t have time _______. I have to work for my family. We need a house. Can you help me?” “ Sorry, I don’t have a house. _________you can cut off my branches (树枝) to build your house.”So the boy cut all the branches of the tree and left _______
The tree was glad to see him happy, but the boy didn’t come after that.
The tree was lonely and sad. One hot summer day, the boy came back and the tree was happy.“Come and play_______me!” the tree said. “ I am sad and getting old. I want to go sailing (航行) to relax_______. Can you give me a _______?”“ Use my trunk (树干) to build the boat. You can sail and be happy.”So the boy_______the tree trunk to make a boat. He went sailing and did not show up for a long time.__________, the boy came back after he left for so many years. “ Sorry, my boy, but I don't have anything for you. The only thing left is my dying roots.” The tree said with tears. " I don’t need much now, just a __________to rest. I am tired after all these years.”
The boy answered. “ Good! Old tree roots are the __________place to rest. Come here, please sit down with me and have a rest.” The boy sat down and the tree was glad and smiled with tears.
This is a story of everyone. The tree is our __________
When we were young, we loved to play with Mom and Dad. When we __________, we leave them, and only come to them when we need something or when we are in trouble. No matter what, parents will always be there and give everything they have to make us happy. You may think that the boy isn't nice to the tree but that's __________all of us are doing to our parents.
1.A.any day B.some day C.one day D.every day
2.A.interested B.excited C.relaxed D.sad
3.A.to play B.to come C.to sleep D.to reply
4.A.So B.And C.But D.Or
5.A.happily B.quietly C.quickly D.finally
6.A.for B.on C.down D.with
7.A.myself B.yourself C.himself D.oneself
8.A.house B.steamboat C.boat D.ship
9.A.cut B.climbed C.killed D.picked
10.A.Luckily B.Finally C.Suddenly D.Happily
11.A.room B.place C.tree D.boat
12.A.worst B.first C.best D.last
13.A.friend B.child C.teacher D.parent
14.A.get up B.stand up C.give up D.grow up
15.A.how B.why C.what D.when
查看答案和解析>>
科目：初中英语 来源：冀教版英语九年级全册Unit5 Look into Science单元测试卷（含听力） 题型：单选题
One of the places of interest are often visited is the Niagara.
A. that B. what C. who D. where
查看答案和解析>>
科目：初中英语 来源：冀教版英语九年级全册Unit5 Look into Science单元测试卷（含听力） 题型：单选题
They will lose the game _______ they try their best.
A.unless B.once C.since D.after
查看答案和解析>>
科目：初中英语 来源：2019年江苏省连云港市海州区中考一模英语试卷 题型：阅读单选
How long does a year last? Children might say that a year lasts forever. But your parents might say that a whole year can pass "in the blink of an eye". Why does time seem to pass faster as we get older?
According to scientists from Duke University, US, our brains degrade（退化）and change over time. This physical change causes the rate at which we take in and deal with new information to fall down.
Babies, for example, move their eyes much more often than grown-ups because they're dealing with images at a faster rate, Adrian Bejan from the university told the Daily Mail. They take in a lot of information and do many things in a single day. This makes them feel like· a single day lasts for a long time.
However, as people's brains degrade over time, fewer images are dealt with in the same amount of time. Therefore, older people receive less information during a day than younger people. This causes things to seem as it they're happening more quickly.
What's more, people may also "feel" time differently due to psychological（心理的）reasons. People may measure time by the number of memorable events that can be recalled（回忆）within a certain period.
Have you ever noticed that when you recall your firsts (first day of school. first family vacation, first birthday party, etc.), they seem to be in slow motion! That's because when something is a "first", there are many exciting things to remember. Recalling these memories makes you feel like they took forever, according to David Eagleman of the Baylor College of Medicine in the US.
For many grown-ups, life is made up of daily things. When they look hack they might feel like there are not many interesting things to remember. Therefore, time seems to be moving faster to them.
1.The phrase "in the blink of an eye" has the similar meaning to "____________".
A.carefully B.directly C.slowly D.quickly
2.Time seems to pass faster as we get older because _____________.
A.human brains become smaller and smaller over time
B.grown-ups often forget things easily and quickly
C.grown-ups don't deal with information as quickly as babies
D.babies are able to do a lot of things in a single day
3.What can we know according to David Eagleman?
A.Babies move their eyes much more often than grown-ups.
B.Psychological factors can affect how a person feels about time.
C.Recalling memories makes people feel like time is going faster.
D.Memorable events can slow down the pace of brain degradation.
4.The author writes this article to ___________________________.
A.explain why people feel time differently as they get old
B.explain why babies learn things faster than grown-ups
C.encourage people to make better use of their time
D.encourage people to create more memorable memories
查看答案和解析>>
科目：初中英语 来源：河北省石家庄市2017-2018学年九年级上学期期末英语试卷 题型：单选题
---I want to borrow the book, but I don’t know how long it may .
--- For two weeks.
A.keep B.be borrow C.borrow D.be kept
查看答案和解析>>
湖北省互联网违法和不良信息举报平台 | 网上有害信息举报专区 | 电信诈骗举报专区 | 涉历史虚无主义有害信息举报专区 | 涉企侵权举报专区
违法和不良信息举报电话：027-86699610 举报邮箱：58377363@163.com
