At GCSE level, from memory you should
be able to list the parts in order of energy (relate how that relates
to frequency and wavelength) and know how they are produced, detected
and their dangers and uses - a rough idea of their approximate wavelength
is also useful at GCSE level (but essential at A level!).
The range of values
for wavelength is so vast that you need to know your S.I. prefixes to
do calculations using the wave equation relating to the EM Spectrum.
radiations are disturbances in an electric field.
travel as waves and move energy from one place to
can all travel through a vacuum and do so at the same
waves cover a continuous range of wavelengths called the
uses and hazards of the radiations in different parts of the electromagnetic
spectrum depend on their wavelength and frequency.
The Electromagnetic Spectrum is a continuous
band of electromagnetic radiation.
It is not made up of particles of
matter - but rather of photons (a concept not met until A level - but the idea is that light is made up of photons which are little
quanta (or packets) of energy)).
Electromagnetic radiation is composed
of rays of pure energy.All electromagnetic
rays have similarities in that they all travel at the same speed in
a vacuum - 3.0 x 108 m/s and are all made up of photons.
differ in their wavelength, frequency, energy and method of production,
but their speed in a vaccuum is always the same.
The parts of the electromagnetic spectrum are
arranged in the table below in order of decreasing photon energy, decreasing
frequency or increasing wavelength.
Each part is named according to its
origin and frequency/wavelength range.
Light energy is the most familiar
part of the spectrum and it is often referred to as the 'family of light'.
Some parts of the e.m. spectrum can be directly detected by humans, others
See the table below:
indicates that the rays are harmful because they are of high enough energy
to be ionizing radiation.
and/or energy can cause heating effects within tissue - whether other
biological effects take place is debatable - some scientist think
it may cause tumour growth - but this is not by the route recognized
(it is none ionizing)