X-rays are electromagnetic waves of very short wavelength.
X-rays can penetrate matter.
X-rays affect a photographic emulsion in the same way that light does.
X-rays cause fluorescence in certain materials.
X-rays cause ionization.
X-rays are
unaffected by electric and magnetic fields.
X-rays cannot easily be reflected or refracted.
X-rays may be
diffracted by passage through
crystals.
Comment on these properties:
Electromagnetic waves are caused by the acceleration of charged
particles. These waves involve electric and magnetic fields vibrating
transversely and sinusoidally at right angles to the direction that the
wave is travelling. The waves do not require a medium for propogation
and travel through a vacuum at 300 million meters per second.
The fact that the
wavelength of x-rays is very short means that their
frequency is very high. This high frequency
corresponds to considerable penetrating ability, which obviously makes
them both useful and dangerous.
X-rays are part of the same family as visible light but cause ionisation
which visible light doesn’t. Ionising radiation
is dangerous and exposure to it must be kept to a minimum.
The short wavelength makes diffraction especially difficult and only
achievable by the tiny gaps found in the lattice
of a crystal.
Wavelength of x-rays … of the order of … one tenth of a
nanometer.
Frequency of x-rays …. of the order of … ten to the power of eighteen Hertz.