Unit 5 Look into Science Lesson 25 Let's Do an Experiment!课件 (共20张PPT)冀教版九年级全一册

(共20张PPT)
Unit 5
Lesson 25
Let's Do an Experiment!
1.学习目标
3.重点探究
2.自主学习
学习导航
5.当堂检测
6.课堂总结
4.拓展提升
新课导入
(1)Do you like science
(2)What kinds of experiments have you done in
science class
(3)If you hold a jar that is filled with water
upside down, what will happen
学习目标
1.掌握本课新单词: science, experiment, fill, prove, scientific, method.
掌握本课短语: do an experiment, fill…with, cover…with, turn…upside down, be (not) sure…
2.增强对科学实验的兴趣
自主学习
experiment
jar
upside
scientific 　
method
pour
correct
raincoat
force
pressure
conclude
实验;试验
广口瓶; 罐子
上部;上边
科学的
方法; 办法
倒出；倾倒
正确的；恰当的
雨衣
力量；迫使，强迫
压力，压强；挤压
得出结论；断定；推断出
重点探究
Think about it!
1. What kinds of experiments have you done in science class
2. If you hold a jar that is filled with water upside down, what will happen
Danny, Jenny and Brian are in the lab.
Brian: Let' s do an experiment. I fill a jar with water. I cover
the top with a piece of cardboard and hold it there.Then I
turn the jar upside down and take my hand off the
cardboard.Can you guess what will happen
Danny: I think the floor will get wet.We should do this
experiment outside, Brian.
Jenny: I think the cardboard will hold the water.
Danny: I don' t think so.
Jenny: You think the water will pour out, Danny. I think the
water will stay in the jar. Let's test which theory is correct.
Brian: Good idea, Jenny. That's called the scientific method.
Jenny: I am so sure of my theory that Brian can do the
experiment over your head and I know you won't get wet.
Danny: Well, let' s try it!
Brian: Are you ready, Danny
Danny: No! Wait! (He puts on a raincoat and sits down.)
Now, I think I' m ready.
Jenny: Brian, take your hand off the cardboard.
Danny: No!(Danny closes his eyes tightly, and Brian takes
his hand off the cardboard.The water stays in the jar:)
Jenny: See, Danny!
Danny: How is that possible
Brian: The force of the air keeps the water in the jar. It is strong
enough to hold the water.
Danny: Wow!
Brian: So what have we discovered
Jenny: We have discovered that the air pressure helps the cardboard
hold the water in the jar.
Brian: Right. What do you conclude, Danny
Danny: I conclude that air is stronger than
I thought.
(1)Where does Danny think they should do the experiment
He thinks they should do the experiment outside.
(2)What keeps the water in the jar
The force of the air.
(3)Is Jenny sure of her theory How do you know
Yes,she is. Because she is so sure of her theory that Brain can do it.
(4)Why does Danny put on his raincoat
In order not to get wet.
(5)What does Danny conclude
He concluded that air is stronger than he thought.
1 Read the dialogue with the following questions.
Let's Do It!
2 Read the experiment.Put the sentence in the correct order on page 67.
2
5
1
3
4
6
Let's Do It!
Put a piece of cardboard over the jar.
The jar of water is upside down , but the water stays in the jar. This is because air pressure pushes the cardboard onto the jar.
Fill the glass jar with water.
Turn the glass jar over quickly . Hold your hand on the cardboard for a few seconds.
Remove your hand from underneath the jar . What happens
There is more air outside the jar than inside, so
there is more air pressure outside than inside.
Task tips:
What happens when you use less water, more water, wet cardboard, or different kinds and sizes of jars
Let's Do It!
3 Try to do the experiment in this lesson yourself.
What Is Science
What is science
Can you explain
Please make it easy for my brain.
It’s about making observations.
Why do onions make me cry It’s about matter—the universe.
Why do clouds go by Why does a car stay on the road
What keeps the birds in the sky Why is there green all over a toad
That’s just science. Why can’t carry a heavy load
That’s just science.
Let's Do It!
4 Listen and sing along.
拓展提升
1.Then I turn the jar upside down and take my hand off the cardboard.
◆turn…upside down意为“把……翻转/倒过来”,相当于turn over。upside down意为“正面朝下”。right side up意为“正面朝上”。
◆take…off…在本句中意为“使……离开/脱离……”或“把……从……拿开”。
【拓展】take off意为“摘掉,(飞机)起飞,脱掉”。
get wet
意为：变湿
get在本句中是系动词，意为“变得”后接形容词作表语
2. I think the floor will get wet.
拓展：get along with与…….相处
get away离开，逃脱
get back 取回，回来，报复
get off 下车，动身
3. be sure of 意为“确信；对……有把握”。
4. put on 意为“穿上”。 “动词+副词”构成的短语。
e.g. I am sure of the fact. 我确信这个事实。
5. pour out：“倒出，使流出，涌出”。　
pour…into…：“把……倒进……”。
6. It is+形容词+enough to do sth.”“做某事是足够……的”。
=too…to…=so…that…
e.g. : He is too old to go to school.
7. conclude from意为“从……推断，从……中得出”。
e.g. : What do you conclude from them
你能从中得到什么结论？
当堂检测
一、用适当的介词填空。
1.The book is covered _______ a piece of red paper.
2.A strange thing happened______ him last week.
3.TV is another way ______ saying television.
4.Dave, please fill the jar ______water at first.
5.Have you read ______the earthquake in the newspaper
with
to
of
with
about
二、根据句意及首字母或汉语提示补全单词。
1．It’s the best m________ of working out the math problem.
2．I’m sure that the f________ of the air will keep the water
in the jar.
3．Can you help me c ________ the mistake that you find
4．Put on the ________ (雨衣) for it's raining heavily.
5．Don't turn the cup ________ (上部) down.
ethod　
orce
orrect
raincoat　
upside
课堂总结
Unit 5
Lesson 25
掌握本课新单词: science, experiment, fill, prove, scientific, method.
掌握本课短语: do an experiment, fill…with, cover…with, turn…upside down, be (not) sure…
增强对科学实验的兴趣