75 All About Light-High

All About Light Written by Brian Roberts

《关于光的一切》布莱恩·罗伯茨著

Introduction Have you ever walked into a room at night and turned off all the lights? Everything is dark. Without light, it is hard to see anything. If you turn on the lights, you can see clearly.

你是否曾经在晚上走进一个房间，把所有的灯都关掉? 一切都是黑暗的。没有光，就很难看到任何东西。 如果你把灯打开，你就能看清楚。

What Is Light? Light is a kind of energy. You can't touch light, but you can see the things it lights up. Your eyes see light and send signals to your brain. Your brain interprets, or tells you what you are seeing. This is how your sense of sight works.

光是什么?光是一种能量。 你摸不到光，但你能看到被它照亮的东西。 你的眼睛看到光并向大脑发送信号。 你的大脑解释或告诉你你所看到的。 这就是你视觉的工作原理。

Sources of Light Some objects can make light. The Sun and a fire make light. A flashlight and a TV screen also make light. Each one is a source of light. Most objects do not make their own light. Clouds and pencils do not make light. You only see them when rays from a light source shine on them. Wowser! A firefly is a light source! Inside its body, the firefly mixes chemicals to give off flashes of light.

光源有些物体能发光。 太阳和火产生光。 手电筒和电视屏幕也能发光。 每一个都是一个光源。 大多数物体本身并不发光。 云和铅笔不能产生光。 只有当光源的光线照射到它们上时，你才能看到它们。 老古板!萤火虫是光源!萤火虫在体内混合化学物质发出闪光。

When Light Shines on Objects Several things can happen when light shines on an object: Almost all the light passes through the object. A little bit soaks into the object and a little bit bounces off. Some light passes through the object. Some of it soaks into the object and some bounces off. No light passes through the object. All of it soaks in or bounces off.

当光照射在物体上时，会发生以下几种情况:几乎所有的光都穿过了物体。 有一点渗透到物体中，有一点反弹出去。 一些光穿过这个物体。 一部分渗入物体，一部分反弹回来。 没有光穿过这个物体。 所有的水都被吸收或反弹。

Light can pass through the air, most glass, and clean water. Only some light passes through wax paper, clouds, and dirty water. No light passes through books and walls. When objects block some or all of the light, they absorb it, or soak it up. Other objects reflect the light. This means light bounces off them. Most objects absorb some light and reflect the rest. Do You Know? The Moon does not make light. Instead, it reflects sunlight that shines on it. Some of that light is reflected toward Earth, which is why you can see the Moon.

光可以穿过空气、大多数玻璃和干净的水。 只有一些光能穿过蜡纸、云和脏水。 没有光能穿过书和墙。 当物体挡住部分或全部光线时，它们会吸收光线。 其他物体反射光线。 这意味着光线会从它们身上反弹。 大多数物体吸收部分光线，并反射其余的光线。 你知道吗?月亮不发光。 相反，它会反射照射在上面的阳光。 其中一些光被反射到地球上，这就是为什么你能看到月球。