15 Energy!

Energy by Liane B. Onish Table of Contents Introduction page 2 Chapter 1 Light Energy page 4 Chapter 2 Heat Energy page 8 Chapter 3 Sound Energy page 12 Conclusion page 14 Glossary/ Index page 15 Comprehension Check page 16

《能源》作者:Liane B. Onish目录引言第二页第一章光能第四页第二章热能第八页第三章声能第十二页结论第十四页词汇/索引第十五页理解检查第十六页

Introduction Do you need energy to run like the wind? Of course you do. But do you need energy to sing a song or smile? Yes, singing and even smiling take energy. You use energy all the time. Energy is the ability to do work. It is what makes things happen, move, and change. You use energy when you read a newspaper or when you shudder in fear at a scary movie. Energy helps your numb fingers form a snowball. Where does the energy you need to run a race, read, or sing come from? Your get-up-and-go, your energy, comes from the food you eat. The energy in the food you eat comes from the sun. There are many different kinds of energy. This book will explore three kinds of energy you use every day: light, heat, and sound. When you read outdoors, you use light energy from the sun. Burning charcoal gives off heat energy for cooking. Singing and playing musical instruments creates sound energy.

你需要能量才能像风一样奔跑吗? 你当然知道。但你需要能量来唱歌或微笑吗? 是的，唱歌甚至微笑都需要能量。 你每时每刻都在消耗能量。 能量是做功的能力。 它使事情发生、移动和改变。 当你读报纸或看恐怖电影时，你会消耗能量。 能量可以帮助你麻木的手指形成一个雪球。 跑步、阅读或唱歌所需的能量从何而来? 你的活力来自你吃的食物。 你吃的食物中的能量来自太阳。 能量有很多种。 这本书将探讨我们每天使用的三种能源:光、热和声。 当你在户外阅读时，你使用来自太阳的光能。 燃烧木炭放出烹饪用的热能。 唱歌和演奏乐器会产生声音能量。

Chapter 1 Light Energy On a sunny day, you can see because of light energy from the sun. The sun does more than just light up the sky. The sun makes life possible. Almost everything that grows needs light energy. Plants absorb light from the sun. Then plants change the sun's energy into energy they can use to grow. Some of that energy is also stored in the plants. When people and animals eat plants, they get the stored energy from the sun. The same energy that helps plants grow also provides food for animals and people. The grass absorbs energy from the sun as it grows. The cow absorbs energy from the sun by eating grass in a field. People get some of the sun's energy that is stored in the cow's milk. See What Happens Plants use light energy from the sun to make food. A green substance in plants, called chlorophyll, absorbs sunlight to help the plant make the food it needs to grow. What happens when plants do not get the light they need? Cover one leaf of a plant with foil. The foil will block out the sunlight. In about five days, the covered leaf will turn yellow, because it was not getting the light it needed to grow. These plants are getting the light they need to grow. The energy we need to grow and stay alive comes from food. When you eat, the energy in the foods changes into a form of energy your body can use. Your body uses the energy to grow and help you stay alive. You use the energy to work and play.

在阳光明媚的日子里，由于太阳的光能，你能看见东西。 太阳不仅仅是照亮天空。 太阳使生命成为可能。 几乎所有生长的东西都需要光能。 植物吸收太阳的光。 然后植物将太阳的能量转化为它们可以用来生长的能量。 其中一些能量也储存在植物中。 当人和动物吃植物时，他们从太阳那里获得储存的能量。 帮助植物生长的能量也为动物和人类提供了食物。 草在生长过程中吸收太阳的能量。 牛通过吃田地里的草来吸收太阳的能量。 人们得到一些储存在牛奶中的太阳能量。 植物利用来自太阳的光能来制造食物。 植物中有一种叫做叶绿素的绿色物质，它吸收阳光，帮助植物制造生长所需的养分。 当植物得不到所需的光照时会发生什么? 用箔纸盖住植物的一片叶子。 铝箔会挡住阳光。 大约五天后，被覆盖的叶子会变黄，因为它没有得到生长所需的光线。 这些植物得到了生长所需的光线。 我们生长和生存所需的能量来自食物。 当你吃东西的时候，食物中的能量会转化为你身体可以利用的能量。 你的身体使用能量来成长，帮助你活下去。 你把精力用于工作和娱乐。

Wear White At Night If you are outside at night, wearing white and shiny fabrics can help you to stay safe. People in cars can see you better when the cars' headlights reflect off your white or light- colored clothing. Shiny silver strips on bikes, helmets, and sneakers also help reflect light. What is light? Light is a wave that travels in a straight line. Light can travel through space, air, water, and some objects. Nothing travels faster than light. That's a good thing, because the light that makes life possible comes from the sun. The sun is 93 million miles from Earth. The sunlight you see and feel right now actually left the sun about eight minutes ago. Sunlight travels in a straight line. Light from a lamp, candle, or other source also travels in a straight line. When light hits an object, some light bounces, or reflects, off the object. The reflected light enters your eyes, letting you see the object. Certain surfaces reflect light. A shiny smooth surface reflects light well. A mirror is a good light reflector. Light can be blocked. A solid object in the path of light blocks it. Blocked light forms a shadow. Light can also be bent. When light passes from air into water, it bends, or refracts. The image of a flower stem in a vase is not broken. It looks broken because light passing through the water refracts. Light appears white, but it is really a rainbow of colors. You see a rainbow when light passes through raindrops in the air. The raindrops bend the light so much that people can see its true colors. You can make a hand shadow like this one by blocking the light rays from a lamp, flashlight, or other source. Water refracts rays of light, making the object in the water appear broken.

如果你晚上在外面，穿白色和闪亮的面料可以帮助你保持安全。 当汽车的前灯反射在你的白色或浅色衣服上时，车里的人能更清楚地看到你。 自行车、头盔和运动鞋上闪亮的银条也有助于反射光。 什么是光?光是沿直线传播的波。 光可以穿过空间、空气、水和一些物体。 没有什么比光传播得更快。 这是一件好事，因为使生命成为可能的光来自太阳。 太阳距离地球9300万英里。 你现在看到和感觉到的阳光实际上是在8分钟前离开的。 阳光沿直线传播。 从灯、蜡烛或其他光源发出的光也沿直线传播。 当光线照射到物体上时，一些光线会从物体上反弹或反射。 反射光进入你的眼睛，让你看到物体。 某些表面反射光。 光滑闪亮的表面能很好地反射光线。 镜子是很好的反光器。 光线可以被阻挡。光线路径上的固体物体阻挡了它。 被遮挡的光线形成阴影。 光也可以被弯曲。当光从空气进入水中时，会发生弯曲或折射。 花瓶里的花茎形象没有被打破。 它看起来是破碎的，因为穿过水的光发生了折射。 光看起来是白色的，但实际上是五彩缤纷的。 当光线穿过空气中的雨滴时，你会看到彩虹。 雨滴使光线弯曲得如此之大，以至于人们能看到它的真实颜色。 你可以通过阻挡来自灯、手电筒或其他光源的光线来制作像这样的手阴影。 水使光线发生折射，使水中的物体显得破碎。

Chapter 2 Heat Energy Heat energy also comes from the sun. It warms the air and melts snow. Heat energy can make matter change. When you add heat to water, it boils. Heat changes water into a gas, called steam. When you take heat away, water freezes. Taking heat away changes water into ice. Heat energy begins with the sun. But heat energy comes from other sources, too. snow water Heat energy from the sun melts snow, a solid, turning it into a liquid, water. Heat energy from electricity boils water, a liquid which escapes as steam, a gas. steam water Taking heat energy away freezes water, a liquid, turning it into a solid, ice. ice water coal oil It takes millions of years for dead plants and animals to turn into fossil fuels. Much of the heat energy we use today comes from burning fossil fuels. Fossil fuels are coal, oil, and natural gas. All fossil fuels were once living plants and animals. These plants and animals died a very long time ago. They became covered with layers of dirt, rocks, clay, and mud. Over millions of years, the remains slowly changed. Some turned into natural gas. Some became a kind of rock called coal. Some remains turned into oil. When we use fossil fuels, we are using energy stored in plants and animals that are millions of years old. However, the supply of fossil fuels is running out.

热能也来自太阳。 它使空气变暖，使雪融化。 热能能使物质变化。 当你给水加热时，它就沸腾了。 热把水变成一种叫做蒸汽的气体。 当你带走热量时，水就会结冰。 带走热量使水变成冰。 热能源于太阳。 但是热能也有其他来源。 来自太阳的热能使固态的雪融化，变成液态的水。 电产生的热能使水沸腾，水是一种液体，以蒸汽的形式逸出，成为一种气体。 把热能带走，使液态的水冻结，变成固态的冰。 冰水煤石油死去的动植物需要数百万年的时间才能转化为化石燃料。 我们今天使用的大部分热能来自燃烧化石燃料。 化石燃料包括煤、石油和天然气。 所有的化石燃料曾经都是活的动植物。 这些植物和动物很久以前就死了。 它们被一层层的泥土、岩石、粘土和泥浆覆盖着。 在数百万年的时间里，这些遗骸慢慢发生了变化。 有些变成了天然气。 有些变成了一种叫做煤的岩石。 一些残骸变成了石油。 当我们使用化石燃料时，我们使用的是储存在数百万年前的植物和动物体内的能量。 然而，化石燃料的供应正在耗尽。