25 L3-Sound And Music

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Oxford Read and Discover level 3 Sound And Music by Richard Northcott

Introduction Listen to the sounds around you. What can you hear? Can you hear cars? Can you hear people's voices? Maybe you can hear a television, or music on the radio. Look at these pictures. What are these sounds? Do you like these sounds? Which sounds are music? What type of music do you like? Discover! Now read and discover more about sound and music!

Chapter 1 How Sound Moves When you speak, sing, or shout, the sound of your voice moves through the air. The sound goes to other people, and they hear it. Sound moves very fast. Discover! Sound moves through air at about 350 meters per second. The sound of a bus moves faster than the bus! How does sound move through the air? The air is made of billions of molecules. The molecules are very small, so you can't see them. Your voice pushes the molecules. The molecules move like waves in the ocean. The movements of the molecules are called sound waves. The sound waves from loud sounds go far. The sound waves from quiet sounds don't go far.

Chapter 2 Low Sounds, High Sounds Some sounds are low and some sounds are high. We can hear low sounds and high sounds everywhere. A plane makes a low sound, but when birds sing, they make a high sound. Think about the strings of a guitar. The thin strings make a high sound and the thick strings make a low sound. The thin guitar strings vibrate fast. You can't see them move. The thick strings vibrate slowly. These different types of vibration are called frequency. The sound of the thin strings has a high frequency. The sound of the thick strings has a low frequency. A baby's cry makes a high sound and it has a high frequency. A truck makes a low sound and it has a low frequency. A baby's cry is made of lots of thin sound waves. The sound waves from a truck are thicker.

Chapter 3 Your Voice Everyone's voice is different. A man's voice is usually lower than a woman's voice. Put your hand on the front of your throat and say something. When you speak, your throat vibrates. In your throat, you have vocal cords. When you speak, air from your lungs goes between your vocal cords, and your vocal cords vibrate. When you sing, you use your mouth, your throat, and your chest. You make your vocal cords shorter or longer, so that you can sing high notes or low notes. Singers can learn how to use their body, so that they can sing better. Some singers have teachers who help them. Discover! Some people in Siberia can sing two notes at the same time. They are called throat-singers.