Electromagnetic Spectrum Flashcards
what is the electromagnetic spectrum in order of frequency from highest to lowest?
gamma rays
x-rays
ultraviolet (UV) rays
visible light
infrared radiation
microwaves
radio waves
what is the electromagnetic spectrum in order of wavelength from shortest to longest?
gamma rays
x-rays
ultraviolet (UV) rays
visible light
infrared radiation
microwaves
radio waves
in the electromagnetic spectrum, the higher the frequency the … the wavelength
in the electromagnetic spectrum, the higher the frequency the shorter the wavelength
what is the electromagnetic spectrum in order of energy from highest to lowest?
radio waves
microwaves
infrared radiation
visible light
ultraviolet (UV) rays
x-rays
gamma rays
what is the electromagnetic spectrum?
a continuous range of wavelengths
what do electromagnetic waves form?
a continuous spectrum
the types of radiation that occur in different parts of the … have different … and …, which depend on their … and …
the types of radiation that occur in different parts of the spectrum have different uses and dangers, which depend on their wavelength and frequency
what is the equation for wave speed?
wave speed (metre per second) = frequency (hertz) × wavelength (metre)
v = f x λ
rearrange the the equation for wave speed to make frequency the subject
frequency (hertz) = wave speed (metre per second) ÷ wavelength (metre)
f = v ÷ λ
rearrange the the equation for wave speed to make wavelength the subject
wavelength (metre) = wave speed (metre per second) ÷ frequency (hertz)
λ = v ÷ f
what types of waves are electromagnetic waves?
transverse
what speed do electromagnetic waves travel at?
the speed of light (299 792 458 m/s or 300 000 000m/s)
what are three uses of gamma rays?
radiotherapy - to kill cancer cells
sterilising medical equipment by killing all the microbes - this is better than trying to boil plastic instruments, which might be damaged by high temperatures
sterilising food by kiling all the microbes - this keeps the good fresh for longer, without having to freeze it or cook it or preserve it some other way - the food is not radioactive afterwards, so it’s perfectly safe to eat
what are three uses of xrays?
to scan bones - X-rays pass easily through flesh but not through denser material like bones or metals
CAT scans
airport scans
what are three uses of UV rays?
sun beds
detecting forged bank notes in shops
fluorescent lights - they use UV radiation to emit visible light
what are three uses of visible light?
to see (sight)
used to make lasers which are used in CDs, DVDs
laser printers
what are three uses of infra red light?
remote controls for television sets and DVD player
security lights
burglar alarms
what are three uses of micro-waves?
microwave ovens
mobile phones
speed cameras
what are three uses of radio waves?
television
aerial TV
radios
what are the dangers of gamma rays?
cause cell damage, causing mutations (which may lead to cancer) and cell death
they cause mutations in growing tissues (which may lead to tissue damage) so unborn babies are especially vulnerable
what are the dangers of x-rays?
can cause cell damage causing mutations (which leads to cancer) and cell death
cause severe burns, leukemia, and cataracts
can speed aging, reduce immunity to disease, and bring about disastrous changes in the reproductive cells
what are the dangers of UV rays?
sunburn
can cause cell mutation or destruction
skin cancer
eye cataracts
premature ageing of the skin
what are the dangers of visible light?
too much light can damage the retina in your eye - blindness
what are the dangers of infra red?
causes skin burns
what are the dangers of micro-waves
cause internal heating of body tissues
cataracts
how do microwave ovens work?
microwaves agitate water molecules in food
as these water molecules get increasingly agitated they begin to vibrate (kinetic energy) and generate heat (thermal energy) - the food cooks
in a microwave oven, the … the molecules vibrate, the … the food becomes
in a microwave oven, the faster the molecules vibrate, the hotter the food becomes
what are the dangers of radio waves?
very large doses (being overexposed) are believed to cause cancer, leukaemia and other disorders
the higher the frequency of an electromagnetic wave, the … the energy it transfers for a given …
the higher the frequency of an electromagnetic wave, the greater the energy it transfers for a given amplitude
the higher the frequency of radiation on the electromagnetic spectrum the … damage it is likely to cause to the body
the higher the frequency of radiation on the electromagnetic spectrum the more damage it is likely to cause to the body
list four similarities that all the parts of the electromagnetic spectum share
they can be dangerous
they are found in the sun
they are transverse waves
they can travel through a vacuum
what two features of characteristic of one electromagnetic wave makes it different from another electromagnetic wave?
frequency and wavelength
what is the potential danger of mobile phones?
microwave radiation is used to transmit signals in mobile phone calls
holding a mobile near you head could mean that the water surrounding your brain is being heated which is a huge danger
however, the intensity of the microwaves is too low to damage tissues by heating, and microwaves are not ionising
Are fluroscent lights more or less energy-effient than filament light bulbs? Where are they used?
Fluroscent lights are more energy-efficient than filament light bulbs
they’re often used in places (like classrooms and officers) where they’ll be needed for long periods
What are the colours of visible light in order of longest wavelength?
What are the colours of visible light in order of highest freuqency to lowest frequency?
violet
indigo
blue
green
yellow
orange
red
How do you remember the colours of visible light (in order of longest wavelength to shortest wavelength)
Richard (red)
Of (orange)
York (yellow)
Gave (green)
Battle (blue)
In (indigo)
Vain (violet)
