Unit Two Electronic Products
Passage One How does a liquid crystal display TV work?
Training target: In this part, our target is to train your reading comprehension. We have made flexible sentences strong black and marked the subject, predicate and object of them. Try to grasp the main idea of these sentences. Have you ever seen a snow crystal? Sometimes it’s possible to see them for a short moment when snow
lands on your hand, but most of the time it melts before you get to see the beautiful hexagon-shaped, (six-sided) crystals. Crystals are made up of particles that are arranged in a regular pattern and usually come in solid form. For example, when snow melts, it turns into water and loses its crystal shape. Do you know that there are three states for most objects: solid, liquid and gas. Most things only come in these three forms. However, some material can remain in a state that is somewhat in between a solid and a liquid. In this state, the object is a liquid but still remains the regular crystal-like arrangements. The existence of this state has been known for a very long time. In fact, there was a research article titled “the flowing crystal”
that was published in 1889, over 100 years ago. It took many, many years of research and development to get liquid crystal display TVs to the point that they are at now. If you put a nail in the middle of two magnets, the edges of the nail will try to point towards each magnet. Similarly, crystals do not have a round shape but have a long narrow shape and when electricity is passed through a crystal, it tries to align itself in the direction of the electrical flow. In a liquid crystal TV, many small compartments are left between two pieces of glass. Each of these compartments holds liquid crystals that are colored red, blue or green. Even if light is shined on the back of the screen, the screen remains black because the liquid crystals are not active and block any light from passing through it. However, when electricity passes through a blue compartment, the liquid crystal in that compartment become active and allow the light through. That’s how a screen becomes blue. The way different
colors are made by combining the three primary colors of light (red, blue and green) is the same as the cathode ray tube TV, but in this case, the shutters of the liquid crystals block or let light pass and that’s how different colors are made. The space
between the two sheets of glass that we talked about before is only 5/1000th of a millimeter. That is 1/10th the thickness of a piece of hair. It’s amazing that people
have invented a way to control the movement of liquid crystals in such small space. What’s more amazing is that people have developed a way to support theses two pieces of glass between such small space without letting it bend or sag. In fact, making a 30〞 ，inches：TV of this size is a very, very difficult task. Another difficult part of the liquid crystal TV is that the screen looks dark from angle because the technology is based upon a shutter closing or opening to allow the light through. Yet, people have found a way to solve these difficulties and made liquid crystal TVs that some said could never be made. You never know what kind of liquid crystal TVs will be around you when you become an adult. Exercises: 【Ex 1】Choose the right
statements according to the passage. 1. 2. 3. 4. 5. Crystals consist of particles
that are arranged in a regular pattern and usually come in liquid form. Most objects exist in three states: solid, liquid and gas.. Just like the nails, crystals have not only round shapes but also narrow shapes. When electricity passes through a crystal, it tries to align itself in the direction of the electrical flow. When light is shined on the back of the screen, the screen becomes motley and even the liquid crystals are not active.
The way different colors of the liquid crystal TV are also made by combining the three primary colors of light (red, blue and green) is the same as the cathode ray tube TV.
Liquid crystal TV presents a wonderful screen whatever angle you take.
【Ex 2】Answer the following questions. 1. 2. 3. 4. 5. What are the three basic forms of most objects? What will happen when electricity passes through a crystal? What are put between two pieces of glass in a liquid crystal TV? What is the space between the two sheets of glass? What is the main question of liquid crystal TV at present? a. 规则类晶体排列 b. 光的三原色 c. 液晶光闸 d. 显像管电视机 e. 结晶 f.
六角形晶体 g. 光闸开关 h. 流动晶体 i. 液晶电视机
【Ex 3】Match the items listed in the following two columns. 1. 2. 3. 4. 5. 6. 7. 8. 9. liquid crystal TV the shutter of the liquid crystals the flowing crystal a shutter closing or opening six-sided shaped crystals regular crystal-like arrangements crystal the cathode ray tube TV the primary colors of light
【Ex 4】Complete following sentences by translating the Chinese in the brackets into English. 1. However, some material can remain in a state that is somewhat in 介于固态和液态之间： ， . In this state, the object is a liquid but still remains the regular crystal-like arrangements. ，between： 2. Similarly, crystals do not have
a round shape but have a long narrow shape and when electricity is passed through a crystal, it tries to (与电流方向平行排列). ，align： 3. Each of these compartments
which are left between two pieces of glass (分别在里面注入红、 蓝 或绿色的液晶).
(hold) 4. When electricity passes through a blue compartment, the liquid crystal in that compartment (活 跃起来,并透出光线). (active) 5. The way of different colors of
the liquid crystal TV is (液晶的光闸关闭或者透过光线). (block or let) 粒子、微粒
regular pattern 规则形状 arrangement 排列、安排 liquid crystal display 液晶显
示器 compartment 间隔
Passage Two How does a washing machine work?
Training target: In this part, our target is to train your reading speed. You should pay more attention to “word group”. Treating a group of words as a whole
unit is a short cut to save your time. We have underlined the word groups in some sentences, and the rest can be practiced by yourself. If there are some new words, you may try to guess their meanings without using the dictionary. Let’s look inside
one of today’s fully automatic washing machines that use swirling water to clean clothes. There are many types of washing machines but most of them are basically made up of: inner wall of the drum, outer wall of the drum, pulsator, motor, cooling fan,
belt and the outlet hose. The reason why a washing machine like this can wash and get water out of the clothes at he same time is because it has a double layer drum. When washing and rinsing, the pulsator spins and makes the water swirl. To get the water out of the clothes, the inner wall of the drum spins and the water goes through the holes. These days, the “centrifugal force washing machines” are quite popular.
This type of machine does not use a pulsator. Instead, the inner wall spins really quickly. When the drum spins, the dirty clothes get stuck to the wall. The water and detergent also try to escape through the holes of the wall but before they do, they are forced to go through the holes. When this happens, the power of the water and detergent removes the dirt from the clothes. Another good thing about this type of machine is that clothes don’t get tangled up so you don’t have to worry about your
clothes getting ripped or damaged. Next, let’s look at some different types of washing
machines. Many of you probably think that the water inside washing machines goes round and round. Actually, different washing machines make water flow in different ways. Whirlpool Type This type of washing machine uses a pulsator to force the water to move like a whirlpool inside the drum. The spinning water forces the dirt out from the clothes inside the machine. Some of the newer models of this type also make the whirlpool move up and down to make it clean clothes even better. Agitator Stirring Type This type of washing machine has something that looks like a propeller at the bottom of the tube. This propeller spins around and stirs the water. The water then forces the dirt out from the clothes in the machine. The good thing about this type of machine is that clothes do not get tangled up and clothe get evenly washed. Drum Type This type of machines has a drum with many holes in it. There are also protrusions bumps along the wall of the drum. As the drum turns, the clothes are picked up by the protrusions. When the clothes fall down from the top of the drum through the water, the movement removes dirt from the clothes. Centrifugal Force Type As we said before, the spinning drum pushes the water and detergent out through the wall of the inner drum. The power that comes from spinning the drum is called centrifugal force, which is where the name comes from. The water is forced through the clothes and then the holes in the inner wall. After one cycle, the water is recycled back into the tank and the process starts again. This cycle is what cleans the clothes! Exercises: 【Ex
1】Choose the right statements according to the passage. 1. 2. 3. 4. 5. The inner of the drum only spins when a washing machine gets the water out of the clothes. The centrifugal force washing machines are quite popular for the home at present. Removing dirt from the clothes is different between drum type and centrifugal force type. The structures of drum type and centrifugal force type are the same. Different washing machines make the water flow in different ways.
【Ex 2】Answer the following questions. 1. 2. 3. 4. How do centrifugal force washing machines get clothes clean? How does water move inside a whirlpool washing machine? Introduce the essential structure of the automatic washing machine briefly. What are the differences between the whirlpool washing machine and centrifugal force washing machine? a. 内槽 b. 传动带 c. 冷却风扇 d. 双层水槽 e. 振动机 f. 外槽 g.
【Ex 3】Match the items listed in the following two columns. 1. 2. 3. 4. 5. 6.
7. a double layer drum inner wall of the drum belt outer wall of the drum cooling fan pulsator centrifugal force type washing
【Ex 4】Complete following sentences by translating the Chinese in the brackets into English. 6. Some of whirlpool type washing machine (能使涡流上下反复旋转；从
而使污垢更容易去 除)；(move up and down) 7. In drum type washing machine, when the clothes fall down from the top of the drum through the water, the movement (使污
垢从衣物中除去). (remove) 8. The adventure of centrifugal force type washing machine is (在水中衣物不会缠绕；也不 会扭曲变形撕破). (tangle up, rip) 9. Centrifugal force
type washing machine does not use a pulsator (而是内槽旋转). (but)
10. The reason why a washing machine can work and get water out of the clothes at the same time (因为水槽是双层结构). (because of )
旋转 涡流 搅拌式 叶轮、螺旋推进器叶片 滚筒式 伸出、突出
pulsator 振动机 whirlpool
agitator stirring type propeller drum type protrusion
Passage Three Refrigerators
Training target: In this part, you should try your best to form good reading habits. In order to avoid your ill habits such as regression, you should keep reading the paragraphs from the beginning to the end without stopping. Now, let’s try to figure
out why refrigerators get cold. First, we have to find out what vaporization heat is. Once we know it, the rest is easy! When you go to the doctors to get your shots (injections), the nurse usually wipes alcohol on your arm with a cotton ball before she puts the needle in your arm. When she does that, that part of your arm feels really cold. The reason why it feels cold is because when liquid alcohol turns into vapor, a process called vaporization, it steals away the heat from the skin on that part of your arm. The heat leaving your skin is called vaporization heat. The reason why sprinkling water on your yard on a really hot summer day makes it feel cool is again because of vaporization heat. The sprinkled water steals the heat away from the ground and turns into vapor. Refrigerators also exchange vaporization heat to become cool. The main way a refrigerator cools down is using vaporization heat to steal heat away from food and then taking it outside. How do you make (or induce) vaporization heat? Compressor: Squeezes the gas and turns it into a liquid. Condenser: Takes the heat away from the refrigerator. Evaporator: Takes the pressure away to turn the liquid back into gas. The vaporization heat taken away at this point is what cools the refrigerator. Now let’s try to figure out how refrigerators exchange vaporization heat. If you look closely at the back of a refrigerator, you will find a lot of tubes that go up and down. These tubes are on every wall, except the door of course. These tubes have gas in them and when the gas is squeezed (or compressed), it turns into liquid. When it is released, the liquid turns into gas again. When the gas exchanges from liquid back to gas again, vaporization heat is removed from inside of the refrigerator. This process is repeated over and over all day long. Until the late 1990s, chlorofluoromethane carbon (CFC) gas was used inside the tubes. But scientists found out that CFCs were actually bad for the environment and nowadays, a different
gas is being used more and more instead. Many companies are now trying to make refrigerators that are CFC free so that they are better for the environment. Exercises: 【Ex 1】Choose the right statements according to the passage. 1. 2. 3. 4. 5. CFC (chlorofluoromethane carbon) gas is bad for the environment. The function of the evaporator is to take the pressure away to turn liquid back into gas. When the liquid turns into gas the heat will be removed from the inside of the refrigerator. Condenser takes the heat away from the refrigerator. On a hot summer day, the reason why the sprinkling water on your yard turns into vapor quickly is because of vaporization heat. 6. The CFC free refrigerator has already gone on the market at present. 【Ex
2】Answer the following questions. 1. 2. 3. 4. What is vaporization? What is vaporization heat? How does refrigerator exchange vaporization heat? What is the function of the compressor? What parts are the refrigerator mainly made up of? a. 压缩机 b. 汽化热
【Ex 3】Match the items listed in the following two columns. 1. 2. evaporator exchange heat
3. 4. 5. 6. 7.
CFC free refrigerator compressor condenser take away heat vaporization heat
c. 带走热量 d. 无氟冰箱 e. 散热器 f. 交换热量 g. 冷却器
【Ex 4】Complete following sentences by translating the Chinese in the brackets into English. 1. 2. 3. 4. 5. Refrigerators exchange vaporization heat (而制冷).
(become) Vaporization heat (从冰箱内部带走). (remove) The process (气体变成液体再
回到气体) is repeated over and over all day long. (from „to) Scientists found out
that CFCs were actually (对环境不利). (bad for) Condenser (带走热量) from the
refrigerator. (take„ away) 电冰箱 棉球 汽化 压缩机 冷却器 蒸发器 碳-氟氯甲烷、碳
refrigerator alcohol cotton ball vaporization sprinkle 洒
compressor condenser evaporator
chlorofluoromethane carbon (CFC) CFC free 无氟的