Eduardo C. Gallenero Jr. Grade 10- Prudence
The EM Wave
What is an electromagnetic wave? How it is
produced? What are the types of EM wave? This are the guide questions that we
are going to find out.
Electromagnetic
wave are waves which can travel through the vacuum of outer space. Mechanical
waves, unlike electromagnetic waves, require the presence of material medium in
order to transport their energy from one location to another.
Electromagnetic radiation consists of
electromagnetic waves, which are synchronized oscillations of electric and
magnetic fields that propagate at the speed of light. The oscillations of the
two fields are perpendicular to each other and perpendicular to the direction
of energy and wave propagation, forming a transverse wave. Electromagnetic
waves can be characterized by either the
frequency or wavelength of their oscillations to form the electromagnetic
spectrum, which includes, in order of increasing frequency and decreasing the
wavelength: radio waves, microwaves, infrared radiations, visible light,
ultraviolet radiation, X-rays, and gamma rays. Electromagnetic waves are
produced whenever charged particles are accelerated, and these waves can
subsequently interact with any charged particles. EM waves carry energy,
momentum and angular momentum away from their source particle and can impart
those quantities to matter with which they interact. A charged particle
produces an electric field. The electric field exerts a force charged particles. Positive charges
accelerate in the direction of the field and negative charges accelerate in the
direction of the field and negative charges accelerate in a direction opposite
to the direction of the field. Also a moving charged particle produces a
magnetic field. This field exerts a force on other moving charges. The force on
those charges is always perpendicular to the direction of their velocity and
therefore only changes the direction of velocity. Since electromagnetic waves
are electric and magnetic field traveling through empty space at the speed of
light, then an accelerating charged particle produces an electromagnetic wave.
The
types of EM wave are the radio waves, microwaves, infrared, visible light,
ultraviolet radiation, x-rays, gamma rays. Radio waves have the longest
wavelengths in the electromagnetic spectrum. These waves can be longer than a
football field or as short as football. Radio is used primarily for
communications including voice, data and entertainment media. Microwaves fall in the range of
the EM spectrum between radio and IR. They have frequencies from about 3 GHz up
to about 30 trillion hertz, or 30 terahertz (THz), and wavelengths of about 10
mm (0.4 inches) to 100 micrometers or 0.004 inches. Microwaves are used for
high-bandwidth communications, radar and as a heat source for microwave ovens
and industrial applications. Infrared (IR) is invisible radiant energy,
electromagnetic radiation with longer wavelengths than those of visible light,
extending fro the nominal red edge of the visible spectrum at 700 nanometers
(frequency 430 THz) to 1 mm (300 GHz). The most common use of infrared in
everyday life is remote controls. These work by sending pulses of infrared that
spell out a message to an electronic device. Infrared can be used in a similar
way for communication. Thermal imaging cameras use infrared to look at
human body heat emissions, both for medical purposes and in night-vision
cameras. Visible light waves are the only electromagnetic waves we can see. We
see these waves as the colors of the rainbow. Each color has different
wavelength. Red has the longest wavelength and violet has the shortest
wavelength. When all the waves are seen together, they make white light. We
concentrate visible light to make lasers to use in everything from
surgery, to CD players to laser pointers. Visible light waves also
make our TV, computer and cell phone screens work. Ultraviolet light is an
electromagnetic radiation with a wavelength from 400 nm to 100 nm,
shorter than that of visible light but longer than X-rays. It can be used to
confirm the validity of banknotes and identity cards. Suitable doses
of Ultraviolet rays cause the body to produce vitamin D, and this
is used by doctors to treat vitamin D deficiency and some skin
disorders. X-rays an electromagnetic wave of high energy and very short
wavelength which is able to pass through many materials opaque to light. The
most familiar use of x-rays is checking for broken bones. Gamma-rays have the smallest
wavelengths and the most energy of any other wave in the electromagnetic
spectrum. These waves are generated by radioactive atoms and in nuclear
explosions. Gamma-rays can kill living cells, a fact which medicine uses to its
advantage, using gamma-rays to kill cancerous cells. Depending on the energy, nearly
all of them, but generally, the higher the frequency, the more dangerous. UV,
X-Rays, and Gamma radiation are all generally harmful. Starting with the most
obviously dangerous, gamma rays are the highest frequency and most energetic
form of light. They penetrate the human body and cause radiation poisoning after
nuclear events like melt downs. Very harmful. X-Rays penetrate skin and muscle
but not bones. They're useful for medical and dental imaging, but if they
interact with your DNA, they can cause cancer. In fact, the first people to die
because of X-rays were shoe salesmen. They used an x-ray device to scan
people's feet and were overexposed to harmful x-rays.
UV rays can interact with your skin and your eyes. They cause you to tan, get a
sunburn, or get skin cancer. Their wavelength allows them to penetrate the top
layers of your skin, and if they interact with your skin cells, they can
develop cancer.
To avoid the harmful effects of EM waves
is that to follow this following ways like cooking and eating without using
microwaves. You can simply heat things up in a conventional oven or a toaster
oven, or just get used to eating cold leftovers! In fact, many people find that
food tastes better and has a better texture when heated in the oven instead of
a microwave, so saving yourself from harmful radiation might have some other
added benefits! The second, people most commonly used laptop and computer in
the way of communications. The
good news is you don’t actually have to give up your laptop to protect
yourself. There are now devices like The DefenderPad that
shield you from the negative health issues related to laptop Electromagnetic
Radiation. Denying the harmful effects of Electromagnetic Radiation won’t make
you immune to them. Your best bet is to educate yourself and find ways to
protect yourself.
BIBLIOGRAPHY:
by Jim Lucas, Live Science
Contributor
