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are waves that are created as a result of vibrations between an electric field and a magnetic field that moves through space at the speed of light

Electromagnetic waves

are waves that are created as a result of vibrations between an electric field and a magnetic field that moves through space at the speed of light.

Electromagnetic wave

highest point of the wave.

crest

lowest point of the wave

trough

distance between crest to crest and trough to trough

wavelenght

the number of waves that pass a fixed point

frequency

These oscillations may occur at very low frequency or at an extremely high frequency and the entire range of frequencies is referred to as

EM Spectrum

The behavior of an electromagnetic wave in a substance depends on itsThe behavior of an electromagnetic wave in a substance depends on its

frequency or wavelength

shortest wavelength to longest wavelength

gammaray xray ultraviolet visiblelight infrared microwave radiowave

are used for communication such as television and radio. • are transmitted easily through air. They do not cause damage if absorbed by the human body, and they can be reflected to change their direction. These properties make them ideal for communications.

radiowaves

are used for cooking food and for satellite communications

microwaves

is used by electrical heaters, cookers for cooking food, and by infrared cameras which detect people in the dark.

infrared

is the light we can see. It is used in fiber optic communications, where coded pulses of light travel through glass fibres from a source to a receiver.

visible light

radiation can kill bacteria that are present in water - this sterilizes the water and makes it safe to drink.

ultraviolet

are ionizing electromagnetic obtained by the decay of an radiation,atomic nucleus.

gamma ray

EM radiation can be described in terms of a stream of particles contain a particle of energy called

photons

planks constant

6.6262x10^-34

can be defined as the process of emitting

radiatiom

These are composed of unstable atoms that give off their excess energy until it becomes stable. The energy emitted is radiation.

radioactive materials

This happens during the spontaneous change to be more stable. One way to describe radioactivity of an element is its half-life, which is the time it takes for half of the atoms of a radioactive substance to decay. Half lives can range from less than a millionth of a second to millions of years.

Radioactive Decay

The standard unit of measurement of exposure to ionizing radiation.

Sievert (sv)

This measure the amount of radiation and in 1 Sv is 100x larger than 1 rem. It is often useful to express the rate at which dose is delivered. Refer to the table

rem (roentgen equivalent man)

associated with long term, low level exposure to radiation;

stochastic effects

appear in cases of exposure to high levels of radiation and becomeappear in cases of exposure to high levels of radiation and become more severe as the exposure increases

Non-Stochastic

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mauigaya · 65問 · 2年前

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