Book 14, Question 27
What Makes One Sound Louder than Another?
A sound is louder when the vibration is bigger! A larger back-and-forth swing pushes the air harder and carries more energy to your ears. A tiny wiggle carries only a little energy, so it sounds quiet.
More fun facts
- Sound happens when energy makes air particles move closer together and farther apart.
- The bigger the size of a sound wave, called its amplitude, the louder the sound.
- A wave with half the amplitude makes a quieter sound.
- Loudness is measured in decibels.
- On the decibel scale, 80 dB is like the sound of 10 vacuum cleaners that each measure 70 dB.
- Dry air absorbs more sound than humid air, especially high sounds.
Sources: National Park Service, National Park Service
Questions kids ask
What is amplitude?
How big the vibrations in a sound wave are. Bigger means louder.