Sound
Sound is created by vibrations that travel through materials. We hear sounds when these vibrations reach our ears and cause our eardrums to vibrate.
What You Need to Know
Key Concept Diagram
Sound is produced when objects vibrate rapidly back and forth
Sound waves travel through solids, liquids, and gases — but not through a vacuum
Pitch describes how high or low a sound is — faster vibrations create higher pitch
Volume (loudness) depends on the amplitude — the size of the vibration
Key Vocabulary
Vibration
A rapid back-and-forth movement that produces sound
Pitch
How high or low a sound is, determined by frequency of vibration
Volume
How loud or soft a sound is, determined by the amplitude of vibration
Vacuum
A space with no matter; sound cannot travel through a vacuum
Knowledge Check
Select the correct answer for each question. Click "Check Answer" to see if you are right.
Question 1
What causes sound?
Question 2
Can sound travel through a vacuum (empty space)?
Question 3
A higher pitch sound means:
Key Concepts Summary
- ●Sound is produced when objects vibrate rapidly back and forth
- ●Sound waves travel through solids, liquids, and gases — but not through a vacuum
- ●Pitch describes how high or low a sound is — faster vibrations create higher pitch
- ●Volume (loudness) depends on the amplitude — the size of the vibration