Left to His Own Devices

Transcription

1 Left to His Own Devices Student A TASK ONE Sit with two other "A" students. What are the names of all the different items? Together with your group, write the words of these things. What are all of these items called? Write the word that describes all of these things in the center of the graph. When you finish, tell the teacher your guess. TASK TWO The teacher will dictate some more words that are important for today's lesson. Listen and write down the words below

2 TASK THREE Communication Game. Find Student "B". Ask him or her about the definition of the words below. Write the definitions in table below. Do not look at your partner's sheet. Use the following dialog as a guide: Student A: Student B: Student A: Student B: What does "energy" mean? It means, "the power from something such as electricity or oil." (Writes the definition in the box). Ok. Thank you. No problem. What does "mechanical" mean? Vocabulary Word Definition Vocabulary Word Definition Energy The power from Power something such as electricity or oil. Mechanical Something about Machines and their parts. Fluid Something that is like a liquid (like water). Device Hydraulic Electrical Prime Mover Something that uses electricity for power or creates electricity Fulcrum Effort The point where a bar is balanced. Lever A bar that has a fixed point, and is used to lift heavy objects. Load BONUS TASK Match the vocabulary words with their Japanese equivalents. Energy Mechanical Device Electrical Prime Mover Lever Power Fluid Hydraulic Fulcrum Effort Load Match the Words 機 械 の 原 動 機 レバー 努 力 電 気 の 荷 重 支 点 エネルギー 流 体 の 装 置 動 力 出 力 パワー 油 圧 の

3 TASK FOUR Pair Work. You are a student. You are asking a teacher (Student B) a question about devices. Read your part of the dialog to your partner. Listen to your partner. Speak when he or she is finished. Do not look at your partner's paper. Hi Mr./Ms. (Partner's Family Name). How are you today? I'm Ok. Do you mind if I ask you something? Well, what is a device? So, anything that is made to do a job is called a device. Can you give me an example? It is a hydraulic brake system. I see.

4 Now I understand. Thank you very much, Mr./Ms. (Partner's Family Name). Ok. Right now I have to go to my next class. Thanks. You too. 'Bye. TASK FIVE Read the article about machines and devices. Answer the questions below. Machines and Devices Machines are devices that can be divided into four broad groups: mechanical, electrical, fluid power, and prime movers. Prime movers convert natural forms of energy, such as those found in streams, wind, and potentially in fuels, into mechanical energy. Common examples of prime movers include the waterwheel, windmill (see WINDMILLS AND WATER POWER) INTERNAL-COMBUSTION ENGINE, and NUCLEAR REACTOR. Fluid-power machines convert mechanical energy to flow energy, as in hydraulic pumps; or convert flow to mechanical energy, as in fluid motors, hydraulic cylinders, and turbines. Similarly, electric machines convert mechanical to electrical energy in such devices as generators and alternators, or convert electrical to mechanical energy in electric motors and loudspeakers. Mechanical machines modify mechanical energy to convert limited input forces and motions into those required to perform specific work. The manner in which a machine modifies and transmits motion is called a mechanism. Although the variety of mechanisms is unlimited, motion is mechanically transmitted in only three basic ways: by a linkage; by direct contact between surfaces such as gear teeth or a cam and follower; or by a wrapping connector such as a belt, rope, or chain. Questions 1. What are the four main groups of machines? 2. What do prime movers do? 3. What are some examples of prime movers? 4. What do fluid power machines do? 5. What are some examples of fluid power machines? 6. What do mechanical machines do?

5 7. What are the three basic ways that motion is transmitted mechanically? TASK SIX Listen now to the instructor. The instructor will give a short presentation about another device, called the lever. As you listen, number the pictures from 1 to 6. TASK SEVEN Find Student "B". Read your information to Student B. Listen very carefully, and write the information that he or she tells you. Do not look at your partner's paper.

6 Left to His Own Devices Student B TASK ONE Sit with two other "B" students. What are the names of all the different items? Together with your group, write the words of these things. What are all of these items called? Write the word that describes all of these things in the center of the graph. When you finish, tell the teacher your guess. TASK TWO The teacher will dictate some more words that are important for today's lesson. Listen and write down the words below

7 TASK THREE Communication Game. Find Student "A". Ask him or her about the definition of the words below. Write the definitions in table below. Do not look at your partner's sheet. Use the following dialog as a guide: Student A: Student B: Student A: Student B: What does "energy" mean? It means, "the power from something such as electricity or oil." (Writes the definition in the box). Ok. Thank you. No problem. What does "mechanical" mean? Vocabulary Word Definition Vocabulary Word Definition Energy The power from something such as electricity or oil. Power Electricity or another force that makes a machine run. Mechanical Fluid Device Electrical A thing or machine that has been made to do a particular job. Hydraulic Fulcrum Something that operates from water pressure. Prime Mover A machine that turns wind or water into energy. Effort The amount of energy that is used to do something. Lever Load Anything that has weight. BONUS TASK Match the vocabulary words with their Japanese equivalents. Energy Mechanical Device Electrical Prime Mover Lever Power Fluid Hydraulic Fulcrum Effort Load Match the Words 機 械 の 原 動 機 レバー 努 力 電 気 の 荷 重 支 点 エネルギー 流 体 の 装 置 動 力 出 力 パワー 油 圧 の

8 TASK FOUR Pair Work. You are a teacher. A student (Student A) is asking you a question about devices. Read your part of the dialog to your partner. Listen to your partner. Speak when he or she is finished. Do not look at your partner's paper. Hello (Partner's FIRST Name). I'm doing fine. How about you? Sure, no problem. What do you want to know? Hmmm. That's a good question. There are many things that are devices. For example, a lever or a pry bar are devices. Machines are also devices. Yes, that's right. Sure. Look at this picture. What is this? Right. This is a device that is used to stop a car or motorcycle. It is made of many smaller devices. The piston, the cylinder, the brake fluid line all of them are devices.

9 The brake system is also an example of a fluid power machine, because it uses a hydraulic pump. You're welcome (Partner's FIRST Name). Next time I'll tell you about another device called the lever. Ok. Have a nice day. 'Bye. TASK FIVE Read the article about machines and devices. Answer the questions below. Machines and Devices Machines are devices that can be divided into four broad groups: mechanical, electrical, fluid power, and prime movers. Prime movers convert natural forms of energy, such as those found in streams, wind, and potentially in fuels, into mechanical energy. Common examples of prime movers include the waterwheel, windmill (see WINDMILLS AND WATER POWER) INTERNAL-COMBUSTION ENGINE, and NUCLEAR REACTOR. Fluid-power machines convert mechanical energy to flow energy, as in hydraulic pumps; or convert flow to mechanical energy, as in fluid motors, hydraulic cylinders, and turbines. Similarly, electric machines convert mechanical to electrical energy in such devices as generators and alternators, or convert electrical to mechanical energy in electric motors and loudspeakers. Mechanical machines modify mechanical energy to convert limited input forces and motions into those required to perform specific work. The manner in which a machine modifies and transmits motion is called a mechanism. Although the variety of mechanisms is unlimited, motion is mechanically transmitted in only three basic ways: by a linkage; by direct contact between surfaces such as gear teeth or a cam and follower; or by a wrapping connector such as a belt, rope, or chain. Questions 8. What are the four main groups of machines? 9. What do prime movers do? 10. What are some examples of prime movers? 11. What do fluid power machines do? 12. What are some examples of fluid power machines? 13. What do mechanical machines do?

10 14. What are the three basic ways that motion is transmitted mechanically? TASK SIX Listen now to the instructor. The instructor will give a short presentation about another device, called the lever. As you listen, number the pictures from 1 to 6. TASK SEVEN Find Student "A". Read your information to Student A. Listen very carefully, and write the information that he or she tells you. Do not look at your partner's paper.

11 Lecture Devices In order to get leverage, a lever must have a fulcrum. How much leverage can be gained depends on the length of the lever, where the fulcrum is placed, where force or effort is applied, and finally, where the load is positioned. There are several different cases, which will yield different kinds of leverage. In one case, the force and the load are on opposite sides of the fulcrum. When the applied force and the load are at equal distances from the fulcrum, the force applied will equal the force to the load. No leverage advantage is gained. But if the fulcrum is moved so that where the force is applied is twice the distance from the fulcrum as the load, only half the effort will be needed to move the load. Leverage will increase proportionally by moving the fulcrum closer to the load. The proportion is called mechanical advantage. An example of this lever arrangement is the gripping capacity of a pair of pliers, and the powerful leverage of a pry-bar. (After Information gap exercise) In another case, the load lies between the load and the point of effort. The closer the load is to the fulcrum, the greater the mechanical advantage. Again, the same rules of proportion are at work. If the effort is three times farther from the fulcrum than the load, the amount of effort needed to move the load is reduced to a third. This lever form is found in a wheelbarrow, and a nutcracker.