Sound Flashcards
If you see a bomb about to land on top of your head, you might think that you should run and go underground. But actually, it's better to just stand there and wait for it to explode on your head. This makes sure you receive optimal damage. -ZackDFilms, probably. (27 cards)
Name two features of sound
pitch - which is either high or low.
volume - which is either loud or quiet.
Frequency is the number of vibrations per ____________.
Frequency is measured in _______ .
The higher the frequency the __________ the pitch.
Frequency is the number of vibrations per second.
Frequency is measured in hertz (Hz).
The higher the frequency the higher the pitch
What is sound caused by?
Vibrations
What is the pitch of a sound?
How high or low a sound is.
What are low pitch sounds caused by?
Slow vibrations
What is frequency measured in?
Hertz (Hz)
What type of wave is sound?
A longitudinal wave.
Are the vibrations parallel or perpendicular to the direction of energy transfer?
The vibrations are parallel to the direction of wave travel
What is the wavelength?
The wavelength is the distance from a point on one wave to the equivalent point on the next wave. (e.g from one peak to the next peak).
What is amplitude?
The amplitude is maximum displacement of a point on a wave away from its undisturbed position.
What is an oscilloscope?
In order to analyse a sound we have to record it using a microphone and an oscilloscope.
The oscilloscope produces an image of the sound wave
How can you tell the volume of a sound using an oscilloscope trace?
Volume is linked to amplitude.
The larger the amplitude the bigger the vibrations.
The higher the amplitude the louder the sound.
How can you tell the pitch of a sound using an oscilloscope trace?
Wavelength is linked to pitch.
The shorter the wavelength, the more vibrations there are every second (higher frequency), the faster the object producing the sound is vibrating.
The shorter the wavelength the higher the frequency the higher the pitch.
The rule for the forces between charges
- and + attract
+ and + repel - and - repel
What is the job of the cell in a circuit?
It provides an electrical current
What is an electric current?
An electric current is the flow of electrons from the negative end to the positive end of the power source.
What type of wave is light?
Transverse
Describe the differences between light and sound waves.
.Light is much faster than sound .Light waves are transverse waves- the vibrations are perpendicular to the direction of energy transfer
. Sound waves are longitudinal- the vibrations are in the same direction as the energy transfer
Why can’t sound waves travel through a vacuum?
Sound waves require a medium to travel. Since the vacuum does not have a medium, no particles can carry the vibrations.
Why does sound travel quicker through a solid compared to a liquid and air?
The more particles there are in a given space, the faster a sound wave travels.
It is much easier for sound vibrations to travel when the particles are packed tightly together, like in a solid.
What happens when sound travels through different mediums?
Hard, smooth surfaces are particularly good at reflecting sound. This is why large, empty rooms produce lots of echoes.
Soft, rough surfaces are good at absorbing sound. This is why rooms with carpets and curtains do not usually produce lots of echoes.
How can the speed of sound be measured by a person?
two people (person A and person B) are placed a distance apart, e.g. 200 m
person A bangs two wooden blocks together
person B starts a stopwatch on seeing the blocks bang together and stops the stopwatch on hearing the sound
Distance divided by time= speed of sound
How can you measure the speed of sound with a computer?
Connect two microphones to an oscilloscope
Label this diagram
Remember that wavelength is between the waves and that amplitude is measured from either over or under the zero reference line (that line in the middle of the trace)
