Unit 5 Look into Science Lesson 25 Let's Do an Experiment 课件(共22张PPT)

(共23张PPT)
Lesson 25
Unit 5 Look into Science
5
Lesson 25
Let’s Do an Experiment！
学习目标
objectives
The new words: experiment, jar, upside, pour, correct, scientific, method, raincoat, force, pressure, conclude
To understand the theory of the experiment.
To learn actively.
Words
experiment
jar
upside
pour
correct
scientific
n. 实验；试验
n. 广口瓶；罐子
n. 上部；上边
v. 倒出；倾倒
adj. 正确的；恰当的
adj. 科学的
Words
method
raincoat
force
pressure
conclude
n. 方法；办法
n. 雨衣
n. 力量
v. 迫使；强迫
n. 压力；压强；挤压
v. 得出结论；推断出
Lead in
Discuss
Do you like to do experiments
What experiments have you done
Listen to the tape and answer the following questions.
1.What’s Danny’s theory
2.What’s Jenny’s theory
Danny thinks the floor will get wet.
Jenny thinks the water will stay in the jar.
Pre-reading
While-reading
Read the lesson and answer the questions.
1.Where does Danny think they should do the experiment
2.What keeps the water in the jar
3. Is Jenny sure of her theory How do you know
He thinks they should do it outside.
The force of the air.
Yes, she is. She thinks that Brian can do the experiment over Danny’s head.
4. Why does Danny put on his raincoat
5. What does Danny conclude
He thinks the water will pour out.
The air is stronger than he thought.
I fill a jar with water.
我用水把瓶子装满。
fill …with…用…装满……
He has filled his case with many books.
他已经把书装满了箱子。
cover…with… 用……盖住……
Language Points
2. I turn the jar upside down.
我把广口瓶倒置。
upside down “向下翻转过来”.
You hold the book upside down.
你把书拿倒了。
right side up “正面朝上”
be sure +that 从句表示“认为…一定…”
而be not sure 表示不确定.
e.g. I’m sure she will come here.
我确信她会来。
I’m not sure when he’ll come here.
我不能肯定什么时候来这儿。
I’m sure the floor won’t get wet.
我确信地板不会湿。
4. We’ll do the experiment and observed what will happen.
我们将做这个实验并观察会发生什么情况。
observed 动词, “观察”。
observe sb. do/ doing sth.
e.g. I observed her dance.
When I passed by the grass, I observed him
walking.
Fill in the blank with the proper word. The first letter is given.
1. Let’s do the e and see what
happens.
2. A “t ” is an idea and predicts what
will happen.
3. We can p who’s right.
4. Turn the jar u down and we can see
what will happen.
5. “O ” is another way of saying
“watch carefully”.
xperiment
heory
rove
pside
bserve
Let’s do an interesting experiment. First, I ____ a jar _____a desk, ____it _____ water, then _____the top ____ a piece of cardboard. When I ____the jar ______ _______, can you guess what will happen
put
on
fill
with
cover
with
turn
upside
down
Post-reading
Let’s Do It !
In a small group, try the experiment above. Try it with the jar full. Try it again with the jar nearly empty. Write down your observations.
Did the experiment work
Did anyone get wet
A balloon is full of air. If we pierce(刺破) it with a needle, it will break with a loud bang. But if we put a piece of glue on the balloon and do the same experiment, what will happen
Surprisingly, we won’t hear the same sound. The balloon will become smaller and smaller. We will feel that the air is running out slowly through the pinhole(针孔). We know the balloon is made of
rubber(橡胶). When the balloon is pierced, the air
leaving the balloon forms a kind of force. Rubber is
so thin that it can’t support(支撑) such force. So
the balloon breaks quickly with a loud bang. But
the glue is different. It’s strong enough to support
the force of the air.
People have learned something from this
experiment. They have used this
method to make tires(轮胎).
I. 根据汉语或首字母提示，完成下列句子。
1. It is the best ________ (方法) of working out the math problem.
2. Have you heard of the ________ (理论）before
3. My daughter likes _________ (科学) more than English.
4. Your answer is wrong, and we can do an experiment to p_____ it.
5. Don't turn the bottle u______ down. It's too dangerous.
pside
method
theory
science
rove
Practice
1. He locked the door ________ (careful) before he left.
2. Let's ______ (finish) the work together now.
3. Can you guess what __________ (happen) in 100 years
4. What's another way of _______ (say) “autumn”
saying
II. 用所给单词的适当形式填空。
carefully
finish
will happen
1. 我确信你是一个诚实的人。
I ______ ______ that you are an honest man.
2. 请用一块玻璃盖上那个杯子。
Please ______ the cup _____ a piece of glass.
3. 小心，否则你会弄湿的。
Be careful, or you'll ______ ______.
4. 把箱子倒过来，你会找到标签的。
______ the box _______ _______, then you'll find the label.
III. 根据所给汉语意思翻译下列句子。
am sure
cover with
get wet
Turn upside down
Homework
Do the experiment by yourself.
Finish the exercise of this lesson.