3 Waves, Sound and EM Spectrum Flashcards
An ambulance is producing sound represented by wave 2
Which wave would represent the sound an observer would hear as the ambulance approached them?
![](https://s3.amazonaws.com/brainscape-prod/system/cm/276/107/232/q_image_thumb.png?1514572404)
Wave 3.
frequency increases and wavelength decreases as the ambulance approaches the observer.
![](https://s3.amazonaws.com/brainscape-prod/system/cm/276/107/232/a_image_thumb.png?1514572669)
What is the use of UV radiation?
flourescent lamps
used to detect conterfeit money
Give three properties (features) common to all EM waves
all travel at the same speed in a vaccum (3 x 108m/s)
all transverse waves
all travel through a vacuum
Which wave has the largest wavelength?
![](https://s3.amazonaws.com/brainscape-prod/system/cm/276/107/235/q_image_thumb.png?1513899630)
wave 1
largest distance between adjacent crests
How can you make a transverse wave with a slinky?
Move your hand in a side to side movement
Equation:
Wave speed v =
wave speed = wavelength x frequency
![](https://s3.amazonaws.com/brainscape-prod/system/cm/276/107/240/a_image_thumb.jpg?1513899899)
Label the compressions, rarefactions and wavelength on the longitudinal wave below
![](https://s3.amazonaws.com/brainscape-prod/system/cm/276/107/241/q_image_thumb.png?1513899570)
![](https://s3.amazonaws.com/brainscape-prod/system/cm/276/107/241/a_image_thumb.jpg?1513899582)
What is 204 nm in m?
n stands for nano (x10-9)
204 x 10-9 m
What is the Doppler effect?
![](https://s3.amazonaws.com/brainscape-prod/system/cm/276/107/243/q_image_thumb.png?1514566487)
When there is a change in frequency of a wave if the source is moving towards or away from an observer.
How can you make a longitudinal wave with a slinky?
move your hand in a forwards and backwards movement
An ambulance is producing sound represented by wave 2
Which wave would represent the sound an observer would hear as the ambulance travelled away from them?
![](https://s3.amazonaws.com/brainscape-prod/system/cm/276/107/247/q_image_thumb.png?1514572404)
Wave 1.
The frequency of the sound would decrease and wavelength increase as the ambulance moves away from the observer.
![](https://s3.amazonaws.com/brainscape-prod/system/cm/276/107/247/a_image_thumb.png?1514572576)
Fred noticed that 10 waves passed a point in 5 seconds. What is the frequency of the wave?
frequency = 10 waves/ 5 s
= 2 Hz
What is 700 µm (micrometres) in metres?
µ = x 10-6
700µm = 700 x 10-6 m
What is a wavefront?
A wavefront connects all points on a wave which are moving in time
![](https://s3.amazonaws.com/brainscape-prod/system/cm/276/107/255/a_image_thumb.jpg?1513901786)
Which wave has the largest amplitude?
![](https://s3.amazonaws.com/brainscape-prod/system/cm/276/107/258/q_image_thumb.png?1513899667)
wave 2
It has the largest displacement from the equilibrium
What is the unit for time period?
seconds or s
What is the unit for amplitude?
metres (m)
Match the following terms with their definition
![](https://s3.amazonaws.com/brainscape-prod/system/cm/276/107/262/q_image_thumb.jpg?1513898953)
frequency- the number of waves going past in one second
wavelength- the length of one repeat of the wave pattern
wave speed- how far a wave travels in one second
Why are UV waves dangerous?
cause blindness
damage surface skin cells and cause skin cancer
What is the use of microwaves?
cook food
mobile phones
satellites to send signals to satellite dishes
What is a transverse wave?
Where the oscillation is 90° to the direction of wave travel
What are the uses of infrared radiation (IR)
heaters
night vision
emitted by tv controllers to control t.v.
What is the use of X-rays?
Used to detect breaks in bones
look inside materials for breaks eg wings of planes