Book 14, Question 4
What Is a Sound Wave Actually Made Of?
A sound wave is made of squeezed and stretched air! Where the air is squeezed, tiny particles bunch together, and where it is stretched, they spread apart. That pattern travels outward, even though the air mostly stays in the same place.
More fun facts
- Sound is a disturbance in matter that travels outward from where it starts.
- When a string vibrates, it squeezes the air in front of it and spreads out the air behind it.
- The squeezed spots have slightly higher pressure, and the spread out spots have slightly lower pressure.
- These high and low pressure spots move outward together, and that is the sound wave.
- For everyday sounds, the air pressure changes only a tiny bit.
- When these waves reach you, they make your eardrum vibrate, and your inner ear turns that into nerve signals.
Sources: openstax.org
Questions kids ask
Can sound break a glass?
Yes. A very loud sound at the same frequency as the glass's natural ring can shatter it.