94 Sound-Mid

Sound Written by Robert N. Knight

作者:Robert N。 骑士

What Is Sound? Can you describe sound? You might say that sound is something we hear with our ears. How does sound move from one place to another? How does sound get to our ears? How do our ears hear sound? This book will help you understand the answers to these and other questions about sound.

声音是什么?你能描述一下声音吗? 你可能会说声音是我们用耳朵听到的声音。 声音是如何从一个地方传到另一个地方的? 声音是如何到达我们的耳朵的? 我们的耳朵是如何听到声音的? 这本书将帮助你理解这些和其他关于声音的问题的答案。

A thick blanket of air surrounds Earth. It is made up of particles so small, they cannot be seen. Sound moves through the particles in air. You hear it when it gets to your ears. Sound is a kind of energy. It has the ability to move things and do work. Sound makes the tiny particles of air vibrate. This means they move back and forth quickly.

一层厚厚的空气包围着地球。 它是由微小到看不见的粒子组成的。 声音通过空气中的微粒传播。 当它进入你的耳朵时，你会听到它。 声音是一种能量。 它有移动东西和做功的能力。 声音使空气中的微粒振动。 这意味着它们可以快速地来回移动。

Think about hitting a ball with a bat. This makes both of them vibrate. It makes the air around the bat and ball vibrate, too. The vibrations move through the air and away from them. The vibrations move farther and farther away. Wowser! Sound moves very fast. Sound near the ground can travel at 1,200 kilometers per hour (750 mph.) But it moves more slowly high above Earth, where air particles are more spread out.

想象一下用球棒击球。 这使得它们都振动。 它使球棒和球周围的空气也震动。 振动在空气中移动，远离它们。 振动越来越远。 老古板!声音传播得很快。 接近地面的声音可以以每小时1200公里(750英里/小时)的速度传播。但它在地球上空移动得更慢，那里的空气颗粒更分散。

How Do Waves Travel? Sound moves through air as waves of energy. These waves are like water waves you see in the ocean. But sound waves travel in every direction from the thing that makes the sound. All sound that you hear comes to you as a sound wave.

波浪是如何传播的?声音以能量波的形式在空气中传播。 这些波浪就像你在海洋中看到的水波。 但是声波从发出声音的物体向各个方向传播。 你听到的所有声音都是声波。

Sound waves are made when particles of air are pushed together and then spread out. Each wave has a regular pattern of particles that are squeezed together and then spread out. Sound waves made by different sounds look different. Let's look at loud and soft sounds.

当空气粒子被推到一起，然后扩散开来，就会产生声波。 每个波都有一个规则的粒子模式，这些粒子被挤压在一起，然后散开。 不同声音发出的声波看起来不同。 让我们来看看响亮和柔和的声音。