5.6 Sound Flashcards
What can sound waves travel through?
Solids, liquids and gases
Which state of matter do sound waves travel fastest in?
Solid
What state of matter does sound travel slowest in?
Gases
What can sound not travel through?
A vacuum
How can we tell that sound cannot travel through a vacuum?
The bell jar experiment. As air is pumped out of the jar, the bell is getting quieter until it fades away
What type of waves are sound waves?
Longitudinal waves
What direction do sound vibrations travel?
The same direction as the wave
What is the range of frequencies that human ears can hear?
20 - 20,000Hz
What happens to your heating abilities as you get older?
Your ability to hear higher frequencies declines with age
How are sound waves demonstrated on diagrams?
As transverse waves
What is made when sound waves are reflected?
Echoes
What surfaces reflect sound?
- hard surfaces
* flat surfaces
What surfaces absorb sound?
Soft surfaces
Name 2 examples of a surface that would reflect sound waves
- floor
* wall
Name 3 examples of a surface that would absorb sound waves
- carpets
- curtains
- furniture
Why will an empty room sound different when furniture, carpet and curtains are added to it?
The waves will be absorbed more
When are sound waves refracted?
At the boundaries between layers of air at different temperatures
What does it mean about its amplitude if a sound wave has a higher frequency?
It’s amplitude is lower
Which waves are faster: light or sound?
Light waves are faster
What is sound caused by?
Mechanical vibrations in a substance that travel as waves
