Sounds and Hearing Flashcards
What are sound waves
Vibrations that pass through the molecules of a medium
What type of wave is a sound wave
Longitudinal
How does a longitudinal wave work
Travels through a series of compressions and refractions
What are compressions in a longitudinal wave
Regions where vibrating particles are closest together
What are refractions in a longitudinal wave
Regions where particles are furthest apart
How do sound waves travel through a solid
Particles vibrate
Collide with neighbouring particles
Pass in the vibrations
What do sound waves travel fastest through and why
Solids , then liquids, slowest is gases
Because the denser the object the faster the sound travels
What can’t sound travel through and why
A vacuum (space)
No particles for the sound to vibrate through
What happens to frequency as sound passes through different medians
Frequency doesn’t change
If frequency doesn’t change and wave speed increases what has to happen
Wavelength must increase
What happens as a wavelength travels through a solid
Wavelength gets longer as sound speeds up
What happens to a wavelength as it travels through a gas
Wavelength gets shorter as sound slows down
What is the pathway of sound as it travels through the ear
Ear canal - ear drum - ossicles - semi circular canals - cochlea - auditory nerve - brain
What makes up the ossicles
A group of 3 small bones
As vibrations pass through the ear what happens when they reach the cochlea
Converts vibrations to electrical signals
What happens when the electrical signals reach the brain
The brain interprets the signals as sounds
What does the brain interpret higher frequencies as
Higher pitch
What does the brain interpret more intense signals as
Louder
What’s the hearing range for humans
20Hz - 20,000Hz
As we get older our hearing range decreases due to wear and tear of what structures in our ear
Cochlea and auditory nerve
