Physics- Waves Flashcards
What is the wavespeed equation?
Wavespeed = frequency ✖️ wavelength V = f ✖️ lambda m/s = Hz ✖️ m
Rearrange the wavespeed equation to have frequency first?
Frequency = wavespeed ➗ wavelength f = v ➗ lambda Hz = m/s ➗ m
Rearrange the wavespeed equation to have wavelength first?
Wavelength = wavespeed ➗ frequency Lambda = v ➗ f m = m/s ➗ Hz
What does amplitude mean?
The height of the wave measured from the middle ( the undisturbed position of the water if observing water )
What is the wavelength?
The distance from one point on a wave to the equivalent point on the next wave
What is the frequency of a wave?
The number of waves produced each second
What is the period of a wave?
The time taken to produce a wave
What is the difference between a wavelength and a wave period?
The wavelength is the distance of a wave where as the period is the time of a wave
What is a wave?
And give a couple of examples
Regular disturbances which carry energy
sound waves, light waves, radio waves, water waves
Top of the wave is called the …..?
Peak
Bottom of the wave is called the ……?
Trough
Refer to figure 1 in draw to check the diagram
.
Why are mirrors good at reflecting light?
Mirrors have a very smooth shiny surface high enables light rays to reflect well
State the law of reflection?
Angle of incidence = Angle of reflection
The angle of incidence and the angle of reflection are always measured between the light ray and the normal line
When drawing a clear reflection ray diagram what equipment would you need? ( 2 objects )?
Ruler
Protractor
Remember the normal is at 90* to the surface
- = degrees
What is refraction?
It’s when light hits the surface and moves direction.
Light travels through transparent materials, why does refraction occur when light enters water?
( they both happen to be transparent materials )
Because they are different materials, ( when light travels from one transparent to another it changes direction = refraction )
What is the angle called that sits between the incident line ( light ray ) and the normal line?
The angle of incidence
Remembering that the normal line is at a right angle to the surface, which way will a light ray turn?
Towards the normal
When moving from (air > glass)or ( air > water)
What is the angle called that sits between the refracted ray ( eg. The one bent in glass ) and the normal line?
Angle of refraction
Which is bigger. The angle of incidence or refraction?
Angle of incidence is always bigger than the angle of refraction ( for a light ray hitting a glass block )
When light comes out of glass into air the angle of refraction is BLANK than the angle of incidence.
Bigger
Why does refraction happen?
Because the speed of movement of the light ray changes when it moves from one medium to another ( this is because the density of the new medium is different
Light hits glass and slows down (angle of refraction is smaller than angle of incidence), what can happen when light leaves glass (to air)?
The light ray speeds up
The angle of refraction is bigger than the angle of incidence (it bends away from the normal)
The incident light ray is ….. ?
The one approaching the medium
When a light ray hits an object, name different things that could happen to it?
Refraction- changes direction
Transmitted though object- passes through
Reflection- away from the object
Why does refraction occur when light hits a glass block?
The glass block is denser than air and causes the light to slow down
T
A
G
Towards the normal going from …..
Air to ….
Glass
A
G
A
Away from the normal going from …..
Glass into …..
Air
Check diagrams for reflection and refraction
CHECK
Is glass denser than air?
Yes
Is water denser than air?
Yes
