Flashcards in Sound Deck (27):
What causes sound?
Sounds are made when an object vibrates.
How many different types of vibrations are there and what are they called?
There are 2 types of vibration.
Compression & rarefaction
When do compressions occur?
When particles are closest together
When do rarefaction occur?
When particles are furthest apart
What kind of wave is sound?
Sound is a longitudinal & mechanical wave.
Can you hear sound in a vacuum. Eg Space
No. In a vacuum there is no air particles to vibrate, therefore, no sound
What state of matter does sound travel fastest in?
Solids. It is the most dense state of matter
How do you calculate speed, distance and time?
Speed = distance/time
Time = distance/speed
Distance = Speed x Time
What is the speed of sound in air, liquid and solid?
Air = 350 m/s
Liquid = 1500 m/s
Solid = 4000 m/s
What happens when we hear sound?
Sounds are collected by the ear lobe
The waves travel along the ear canal
The waves make the ear drum vibrate
The small bones (ossicles) amplify the vibrations
The cochlea turns these into electrical signals
The auditory nerve takes these signals to the brain
What is the human hearing range
20 - 20,000 Hz
How does wax in the ear occur and how to we fix it?
Wax in the ear is caused by an over reactive gland. You would fix this with a syringe in the ear
How is a perforated eardrum caused and how do we fix it?
A very loud noise Eg Explosion
Small holes will heal over time while larger holes may need a skin graft.
How is an earache caused and how do we fix it?
Cussed by infection. You would need antibiotics to fight the infection.
How is tinnitus caused and how do we avoid it?
Tinnitus is caused by regular loud noise, all you need to do to get rid of it is to avoid loud noises.
How is limited movement of the ossicles caused and how do we fix it?
Limited movement of the ossicles is caused by old age, this is cured with hearing aids to amplify the vibrations.
What is noise
An unwanted sound.
A form of pollution.
What can nosies do?
They can make you feel ill
Make you temporarily blind
Make you tired and short tempered
Damage your hearing
How can you reduce noise?
Wear ear protectors.
Don’t make the noise if possible
Sound dampening (eg acoustic foam, ear protectors etc.)
Distance yourself from the source
What can sound waves be studied with?
An oscilloscope, signal generator and loudspeaker
How can we tell the volume of the sound wave?
The height of the wave
How can we tell the pitch of a sound wave?
The frequency of waves, how many there are.
Look at your ear diagram in your book, label it.
How did you do?
What is the function of the ear drum?
When sound waves reach the ear drum, it vibrates.
What are the ossicles?
Small bones called the hammer, anvil and stirrup. These bones help make vibrations louder.
What is the oval window?
The oval window has a smaller area than the ear drum and passes bigger vibrations to the cochlea