Waves And Their Properties Flashcards
Frequency
the number of waves that pass a fixed point in a certain unit of time
How to work out frequency
No. Of waves past a point/time
Measured in hertz
Amplitude
Maximum distance a point moves from its rest position in the middle
The larger the amplitude…
The greater the energy of the wave
Amplitude of transverse wave
Height of a peak or trough from the rest position of the wave
Wavelength
The distance between two matching points on neighbouring waves
What are peaks
The high points of a transverse wave
Troughs
The low points of a transverse wave
Examples of transverse waves
Water
EM - eg. Light
Describe the movement of transverse waves
The particles move up and down so the direction of their movement is at right angles to the direction of the wave
Describe the movement of longitudinal waves
The particles vibrate back and forth so the direction of their movement is parallel to the direction of the wave
In a longitudinal wave, the coils do not travel horizontally.. each coil of the slinky
Just vibrates left and right
compressions
region in a longitudinal wave where the particles are closest together
Rarefractions
region in a longitudinal wave where the particles are furthest apart
What are P waves
primary waves produced by earthquakes
longitudinal ,
push and pull the earth
What are S waves
Secondary waves produced by earthquakes
Transverse waves
Shake the earth from side to side
Examples of longitudinal waves
Sound
Ultrasound
P waves
Connection between speed frequency and wavelength
Speed = frequency x wavelength
What is a longitudinal wave?
A type of wave in which the particles vibrate back and forth, parallel to the direction of the wave’s travel
E.g. sound + P waves
What is a transverse wave?
A type of wave in which the particles vibrate up and down at right angles to its direction of wave travel. Eg. Em + water + S waves
The larger the amplitude of the wave on the trace..
The louder the sound
Oscilloscope
Shows wave pattern and allows us to ‘see’ sound
The greater the number of waves across the oscilloscope trace..
the higher the frequency and pitch.
What happens when a sound wave meets a hard flat surface?
The sound wave is reflected back from the surface - echo
Hearing range
The range of frequencies a person can hear
hearing range of a healthy young person
20 - 20000 Hz
Decibel
The unit for measuring the loudness of a sound (dB)
Wave
An oscillation that transfers energy
What do mechanical waves require that EM waves don’t
A medium (matter) to travel through
Time period
The time for one wave to pass a given point
There are two ways to represent a wave. What are they
Time trace
Snapshot of wave
What do these representations do
TT- shows how displacement varies with time at a particular position
SW- shows how displacement varies with distance at a particular time
