Electromagnetic waves are transverse waves that are created by oscillating electric and magnetic fields. They exhibit properties of reflection, refraction, and energy transfer. Electromagnetic waves vary in wavelength from long radio waves to very short gamma rays, with shorter wavelengths corresponding to higher energy. The electromagnetic spectrum maps all electromagnetic waves according to their frequency and wavelength, ranging from radio to gamma rays. Examples of uses of different electromagnetic waves include communication with radio waves, cooking with microwaves, infrared for TV remotes, visible light, ultraviolet from the sun, x-rays for medical imaging, and gamma rays for cancer treatment.

1. ELECTROMAGNETIC WAVES

2. What is an Electromagnetic wave?
Electromagnetic waves or EM waves are
waves that are created as a result of
vibrations between an electric field and a
magnetic field. In other words, EM waves are
composed of oscillating magnetic and electric
fields.

3. Properties of Electromagnetic waves
Electromagnetic waves are transverse waves.
Electromagnetic waves can travel through a vacuum.
Electromagnetic waves travel at the same speed in a
vacuum, the speed of light.

4. Properties of Electromagnetic waves
It can be reflected
It can be refracted
Transfers Energy

5. Types of Electromagnetic waves in
terms of there wavelengths.
One thing that differentiates electromagnetic
waves is their wavelength. The wavelength is
defined as the distance between one wave
crest to the next. Electromagnetic waves vary in
size. Their sizes range from very long radio
waves to very short gamma rays. The amount
of energy produced depends on the size of the
wavelength. The smaller the wavelength, the
higher the energy. Examples of smaller
wavelength-higher energy are x-rays and
gamma rays. Examples of bigger wavelength-
lower energy are microwaves, radio waves, and
television waves.

6. An electromagnetic
spectrum is the entire
distribution of
electromagnetic
radiation according to
frequency or
wavelength.

7. • A spectroscope is an
instrument that can be
use for visual
observations. The first
person to observe the
spectrum of a comet
was Giovanni Battista
Donati who was an
Italian astronomer.

8. Sources of electromagnetic waves
• Electromagnetic waves are waves that consist of vibrating
electric and magnetic fields. They transfer energy through
matter or across space. The transfer of energy by
electromagnetic waves is called electromagnetic radiation.
Electromagnetic waves are formed when an electric field
couples with a magnetic field. The magnetic and electric fields
of an electromagnetic wave are perpendicular to each other and
the direction of the wave.

9. Types of Electromagnetic
waves

10. Radio Waves
These are the longest wavelength
electromagnetic waves that are used for
communicating information from radio,
satellites, and radar. They range from almost
around a foot long to several miles long.

11. Microwaves
• These waves are estimated in centimetres
and are used for communicating data and
for cooking food. Moreover, radar helps in
forecasting the climate. Microwaves are
valuable in communication since they can
enter clouds, smoke, and light rain. The
universe is loaded with cosmic microwave
background radiation that researchers
accept are hints to the origin of the universe
they call the Big Bang.

12. Infrared Waves
These waves are also called all-over infrared. The human
body is an example of a body that radiates infrared waves. In
between microwaves and visible light are infrared waves.
Infrared waves are sometimes classified as "near" infrared and
"far" infrared. Near to infrared waves are the waves nearer to
visible light in frequency. These are the infrared waves that are
used in our TV remote to change channels. Far infrared beams
are further away from visible light in wavelength. Far infrared
waves are warm and radiate heat. Anything that emits heat
radiates infrared waves. This also includes the human body!

13. Visible Light
The visible light range covers the frequencies
that should be visible to the human eye.
Visible light wavelength ranges between 390
and 700 nm.

14. Ultraviolet waves
Ultraviolet waves are acquired from the Sun.
Ultraviolet waves have the following shortest
frequency after visible light. Ultraviolet beams
from the Sun cause sunburns. We are
safeguarded from the sun's ultraviolet rays by
the ozone layer. A few insects, like honeybees,
can see ultraviolet light. Ultraviolet light is used
by strong telescopes like the Hubble Space
Telescope to see faraway stars.

15. X-Rays
• X-rays: These light beams are used for
medical purposes to take pictures of
bones. X-rays have much shorter
frequencies than ultraviolet rays. At this
point in the electromagnetic range,
researchers consider these rays more as a
greater number of particles than waves. X-
rays were found by German researcher
Wilhelm Roentgen. They can enter delicate
tissue like skin and muscle and are utilised
to take X-ray pictures of bones in
medication.

16. Gamma Rays
These beams are the shortest waves in the
electromagnetic spectrum. As the
frequencies of electromagnetic waves get
shorter, their energy increases. Gamma rays
are the shortest waves in the spectrum and,
accordingly, have the most energy. Gamma
rays are sometimes used in treating cancer
and in taking detailed pictures for diagnostic
medication. Gamma rays are created in high-
energy nuclear blasts and cosmic explosions.

17. Thank you for listening
to our presentation!