You're listening to Sleep Tight Science. Do you know what is louder than a car horn?

Hmm.

The cry of a human baby.

What?

Which is about 115 decibels.

Okay. decibels. Hello friends and welcome back to Sleep Tight Science, a bedtime show that answers your questions about science. What do you think sound is?

A simple definition for us is that sound is anything that can be heard.

My voice, the background music, the barking of a dog, rain or other weather,

and your alarm in the morning are all sounds. In this episode, we will start to learn all about

the science of sound and try to answer some of the

questions that our listeners have submitted about this topic. Before we answer some of the

questions, let's learn some basic facts first.

Three things need to happen for a sound to be made and heard.

First, an object vibrates.

Sound is a type of energy made by vibrations. A vibrating object makes tiny, very fast, back-and-forth movements.

When that object vibrates, it causes movement in the air particles.

These particles bump into the particles close to them,

which makes them vibrate too,

causing them to bump into more air particles.

This movement, called sound waves, keeps going until they run out of energy.

You hear the sound if your ear is within range of the vibration.

For example, when a musician strums guitar strings, they vibrate.

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