Properties of waves 2.0 Flashcards
what does constant frequency mean in relation to wave velocity and wavelength?
the wavelength will be proportional to the wave velocity.
describe the movement of particles in the process of transferring sound to a person’s eardrums: (2)
-when sound is created, air particles vibrate and collide with each other, causing the vibrations to pass between air particles.
-vibrating particles pass the sound through to a person’s ear and vibrate the ear drum.
equation for the speed of sound: (word and symbol)
speed (m/s) = distance (m) / time (s)
v = x/t
‘An observer 400 m away records a 1.2 s time difference between seeing the hand signal and hearing the bang of the starting pistol’
explain why the results of this experiment may be flawed: (2)
-humans do not use stop clocks identically to one another since they have different reaction times
-the values recorded will be dependent on the reaction time of the observer, and will not be entirely accurate
outline how the velocity of sound in air can be measured: (2)
-a person fires a starting pistol and raises their hand in the air at the same time.
-distant observer standing 400 metres (m) away records the time between seeing the action (the light reaches the timekeeper immediately) and hearing the sound (which takes more time to cover the same distance).
what is the speed of sound through air?
330 m/s
what does the speed of sound depend on?
the medium that it is travelling through
can sound travel through a vacuum?
-no
-because there are no particles to carry the vibrations
define ‘interface’:
boundary
what happens to waves transmitted at the interface (boundary) between two materials?
they may change direction.
define ‘refraction’:
the change in direction of a wave at a boundary.
what can all wave types be?
refracted
A useful way of remembering the speed and direction changes of waves during refraction is ‘FAST’:
Faster - Away / Slower - Towards
