Sound can't travel through empty space — it needs something to travel through. Explore how sound moves, and why it travels faster through some materials than others.
Sound travels as vibrations through a medium — solid, liquid, or gas. Because there are no particles to vibrate in a vacuum, sound cannot travel through empty space.
Why can astronauts not hear sound travelling directly through the vacuum of space?
Because sound needs a medium (particles) to travel through, and there are no particles in a vacuum to carry the vibrations
Sound generally travels fastest through solids, slower through liquids, and slowest through gases, because particles are packed more closely together in solids, transmitting vibrations more quickly.
Does sound travel faster through water or through air?
Through water — sound travels faster in liquids than in gases, since liquid particles are more closely packed
Frequency is the number of vibrations per second, measured in hertz (Hz). Time period is the time taken for one complete vibration, and is the reciprocal of frequency:
A sound wave has a frequency of 50 Hz. Find its time period using T=1/f.
T = 1/50 = 0.02 seconds
1. Can sound travel through a vacuum?
2. Does sound travel faster through a solid or a gas?
3. A sound wave has a frequency of 20 Hz. Find its time period using T=1/f.
4. What is frequency measured in?
5. Why does sound generally travel fastest through solids?