Electromagnetic Waves 2 Flashcards
What do electromagnetic waves form?
A continuous spectrum
What are uses of gamma rays?
Medical imaging
Radiotherapy
How are x-rays produced?
By the rapus deceleration of free electrons
By changing in the organisation of the elctribs that orbit the nuclei of atoms
What are uses of X-rays and why?
Pass easily through soft body tissue but are absorbed more effectively by bone
Medical imaging
Medical treatment
What are hazards related to UV radiation?
Sunburn
Skin cancer
Blindness
What are uses of UV?
Process called fluorescence
A fluorescence substance can absorb UV radiation
The emits longer-wavelength visible light
Energy saving light bulbs
Security ink
Smarrwater
What are high frequency hazards?
Gamma, X and UV rays lie at the high frequency of the spectrum
The energy they deposit within the body can ionise the atoms that make up cells
This can lead to mutations to cells in the body which can cause cancer
What is radiation dose what is the unit
The dose we receive from an exposure to one of these types of electromagnetic radiation tells us how harmful it is likely to be on our health
Sievert, Sv
How many Sievert does the average person in the UK receive?
2.7 mSv from all sources of background radiation
What are uses of visible light?
Human sight
Lasers
Fibre-optic communication
What is the order of the 7 main colours of the visible spectrum?
Red - Richard
Orange - Of
Yellow - York
Green - Gave
Blue - Battle
Indigo - In
Violet - Vain
What is another way to refer to infrared radiation?
Thermal radiation
What are uses of infrared?
Electrical heaters
Cookers
Infrared cameras
What are uses of Microwaves?
Microwave oven
Mobile phone networks
Satellite communications
Bluetooth
Why are microwaves used for satellite communication?
Pass easily through the Earth’s Atmosphere
