Waves Flashcards
What is a wave?
An oscillation or vibration passing through a medium
It transfers energy but not matter
How do particles move in a wave?
They oscillate around their rest position, they each push ot pull on their adjacent particles
What are the 2 types of wave?
Transverse and longitudinal
What are transverse waves?
Waves where the oscillations of particles are at right angles to the direction of the energy transfer of the wave
They cannot pass through liquids or gases
What are longitudinal waves?
A wave where the oscillations of the particles are parallel to the direction of the energy transfer of the wave.
This causes areas of compression and rarefaction
What type of waves are sound waves?
Longitudinal
What is wavelength, its symbol and units
The distance between two equivalent points in aadjacent waves. The distance of one complete oscillation
λ
Metres, m
What is displacement?
The distance and direction of a vibrating particke from its rest position
What is amplitude?
The maximum displacement of a vibrating particle
What is a crest of a wave?
The top
What is the trough of a wave?
The bottom
What is the period, its symbol and unit?
The time it takes for one complete oscillation to pass a fixed point
T
seconds, s
What is frequency, its symbol and unit?
The number of complete waves passing a fixed point per second
f
Hertz, Hz
What is the equation that shows the relation between period and frequency?
1
f = –
T
What is the equation for wave velocity?
V = f λ
What is the speed of sound?
340 m/s
How to calculate uncertainty?
½ × range
How to calculate percentage uncertainty?
Mean
What is an echo?
A reflected (sound)wave, which must travel to the boundary and back
REMEMBER TOTAL DISTANCE = 2X REAL DISTANCE
What can happen to a wave when it reaches a boundary?
It can be reflected, absorbed, or transmitted
In which mediums does sound travel faster?
Denser mediums
What happens to a soundwave when it enters a denser medium?
Speed increases, but frequency stays the same so wavelength increases
What is the range of frequencies we can hear called, and what is it?
The auditory range
Between 20Hz and 20,000 Hz
What is an oscilloscope?
An instrument that can be connected to a microphone to visualise sounds. The greater the amplitude of the sound the higher the potential difference induced into the microphone