Topic 4 Waves Flashcards
What is wavelength?
distance between the same points on two consecutive waves (waves following each other)
What is amplitude?
Distance from the equilibrium line to the crest (highest part of wave)
What is a period?
Time taken for a whole wave to completely pass a point
What is a wavefront
Imaginary surface representing corresponding points of a wave that vibrate in unison
In which direction do transverse waves travel
perpendicular to the direction of energy transfer
In which direction do longitudinal waves travel?
Parallel to the direction of energy transfer
Examples of transverse waves
Water, light, radio, microwaves, seismic S waves
Examples of longitudinal waves
sound, seismic p waves
Where do transverse waves travel
Travel through a vacuum
Where do longitudinal waves travel
Through a medium
Why is a smoother surface better for reflection?
The smoother the surface the stronger the reflected wave
What happens when light is reflected on a rough surface?
rough surfaces will scatter light in all directions so appear matte and not reflective
What is the equation from finding the velocity?
Frequency x wavelength
What is the equation for finding the wavespeed?
Frequency x wavelength
What is frequency?
Number of waves that pass a single point per second
What is refraction
When waves pass from one medium to another
What happens if a waves passes through a more optically dense medium
The wave will be refracted at the boundary and will change direction to bend towards the normal
- the speed will decrease
- and the wavelength will decrease
What are the effects of wavelength
Different substances may absorb, transmit, refract or reflect waves depending on their wavelength
How is the velocity of sound in air measured
- make a noise 50m from a solid wall and record how long it takes for an echo to be heard
- use the speed = distance/time equation
How is the velocity of ripples on a water surface measured
- use a stroboscope which has the same frequency as the water waves
- measure distance between the fixed ripples
- use velocity = frequency x wavelength
