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Electromagnetic
waves are present in every environment where alternating electrical
current is generated. Visible light represents only a small portion
of the electromagnetic spectrum that ranges from ionizing radiation
(i.e. X-rays and gamma rays) to non-ionizing radiation - extremely low
frequency electromagnetic waves. In reality, between these two extremes,
other types of electromagnetic waves are present. These include radio
frequencies, infrared waves, visible light, microwaves and ultraviolet
light. Electromagnetic waves are also present naturally in the environment:
the sun, the planets and the stars all radiate electromagnetic waves
which affect life on earth in different ways. Just like other forms
of energy, electromagnetic waves have properties such as wave length,
amplitude, frequency and power. The energy radiating from a source diminishes
proportionally to the increasing distance from the source itself. The
growing use of electric and electronic devices is increasing the level
of electromagnetic waves within our environment. Because of this, we
face growing concerns about their potentially dangerous impact on the
environment and on our personal health. What are the effects of microwave
ovens, computers, mobile phones, pagers, radio transmitters, electric
pylons, overhead power lines and powerful transmitting stations on our
lives? The answer can only be found by understanding more clearly the
properties of electromagnetic waves and their affect on the human body.
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