Sound Flashcards
Are sound waves longitudinal or transverse?
Longitudinal
In what way do sound waves vibrate/travel?
As they are longitudinal waves, sound waves vibrate/travel parallel to/in the same direction the wave is transferring energy in
What is the range a human can hear?
20Hz-20000Hz
How does the density of an object affect the speed sound travels?
The denser the object, the faster the sound will travel through it
Can sound waves travel through a vacuum?
Sound waves cannot travel through a vacuum because there are not any particles
How can sound waves be moved?
Sound waves can be reflected, refracted or diffracted
State the definition of reflected
When a wave is bounced off a surface
State the definition of refracted
When a wave changes direction
State the definition of diffracted
The spreading out of waves when they pass through a gap
How do you measure the speed of sound experimentally?
1) Two people stand a distance of around 100m apart.
2) The distance between them is measured using a trundle wheel.
3) One of the people has two wooden blocks, which he bangs together above his head.
4) The second person has a stopwatch which he starts when he sees the first person banging the blocks together and stops when he hears the sound.
5) This is then repeated several times and an average value is taken for the time.
6) The speed of sound can then be calculated using the equation - speed = distance/time
What is an oscilloscope?
An oscilloscope is a machine that shows the wave shape of an electrical signal. When connected to a microphone they can show the wave shapes of sounds.
How does the amplitude affect the sound of a wave?
The larger the amplitude, the louder the sound because more amplitude = more energy
How does frequency affect the pitch of a wave?
The higher the frequency, the higher the pitch
What is frequency?
The number of complete vibrations per second
