The document is an educational assessment focused on electromagnetic waves and their properties, including questions about the visible spectrum and wave characteristics. It explains the electromagnetic wave theory, the production and propagation of different wave types, and their applications in daily life. Additionally, it provides objectives for students to understand and compare electromagnetic waves, as well as activities for engagement and learning.

5. Instruction: Choose the letter of the correct
answer.
Pretest - Assessment
1. Which two waves lie at the ends of the
visible spectrum?
a. Infrared and Ultra-violet rays
b. Radio waves and Microwaves
c. Radio waves and X-rays
d. X-rays and Gamma rays

6. 2. In the visible spectrum, which color has the longest wavelength?
a. Blue
b. Green
c. Red
d. Violet
3. Which property spells the difference between infra-red and ultra-
violet radiation?
a. Color
b. Speed in vacuum
c. Wavelength
d. None of the above

7. 4. A certain radio station broadcasts at a frequency of 675 kHz. What
is the wavelength of the radio waves?
a. 280 m
b. 324 m
c. 400 m
d. 444 m
5. What type of electromagnetic waves is used in radar?
a. Infrared rays
b. Microwaves
c. Radio waves
d. Ultra-violet rays

8. Directions: Show a pictures
of different communication
devices such as radio,
cellphones, TV and medical
equipment’s such as x -ray.
Ask the uses of it.

9. Next avatar

12. Direction: A group
of students will
arrange the
scramble words to
the correct
terminologies and
give a short
description about

13. Magneto electric CRUMPETS
ELEECTROMAGNETIC
SPECTRUM

14. DISAVOWERS
RADIO WAVES

15. MMGAA YASR
GAMMA RAYS

16. ERDANIFR YARS
INFRARED RAYS

17. OASCIRWEMV
MICROWAVES

18. spectrum with the
same group of
students. Create a
graphic organizer
indicating the list of
the wavelength,
frequency and
energy of each
electromagnetic
waves.

19. ELECTROMAGNETIC SPECTRUM

20. Explain the
following
questions that
refers to the
last activity we
had.

21. 1. Which among the EM waves has the highest
frequency? _________________
2. Which among the EM waves has the lowest frequency?
__________________Q3.
3. The energy of an EM wave also depends on its
frequency, which means waves with higher frequency
has higher energy too. Which among the EM waves has
the highest energy? __________________________
4. Which among the EM waves has the lowest energy?
_____________________
5. What happens to the frequency of the electromagnetic
waves as it progresses? Does the frequency of the EM
waves increase or decrease as we go from radio wave
to gamma ray? _______________________

22. ELECTROMAGNETIC
SPECTRUM
-JEALLEA S. AENLLE

23. Objectives
At the end of this lesson, the students can:
a. describe how electromagnetic wave is
produced and propagate;
b. compare the relative wave of different
forms like wavelengths, frequencies, and
energies of the different regions of
electromagnetic spectrum;
c. appreciate the useful application of
electromagnetic waves in daily life activities

24. The concept known as electromagnetic wave
theory originated with the work of James Clerk
Maxwell and Heinrich Hertz. According to the
electric and magnetic equations postulated by
Maxwell, electromagnetic fields resemble a wave in
both structure and action. Electromagnetic waves
coincide with the measurement of the speed of
light, making light an electromagnetic wave
itself.
ELECTROMAGNETIC WAVE THEORY

25. The electromagnetic wave theory states that any acceleration of
an electric charge or change in the magnetic field produces
radiation. This radiation can come in the form of either a wave or a
particle. Velocity, wavelength and frequency are the factors
associated with waves.

26. Electric field, an electric property associated
with each point in space when charge is
present in any form. The magnitude and
direction of the electric field are expressed
by the value of E, called
electric field strength or electric field
intensity or simply the electric field.
Magnetic fields - is a picture that we use
as a tool to describe how the magnetic
force is distributed in the space around
and within something magnetic. arise
from permanent magnets and electric
charges in motion. Magnetic fields
ultimately are the result of the motion
of charges.

27. Basic properties of waves:
Amplitude, wavelength, and
frequency

28. All electromagnetic waves can travel
through a medium but unlike other types of
waves, they can also travel in vacuum. They
travel in vacuum at a speed of 3X10 m/s and
denoted as c the speed of light The wave
speed, frequency, and wavelength are
related by the following equation:
v=λf
where v is the wave speed or c (speed of
light) expressed in meters per second, the
frequency f is expressed in Hertz and the
wavelength A is expressed in meters

29. Since all the EM waves have the same speed
and that is equal to the speed of light, as
wavelength decreases, the frequency of the
wave increases
Through the years the advancement on the
knowledge about electromagnetic waves
led us to a modern technological world

30. Radio Waves
Refers to electromagnetic radiation with
wavelengths greater than about 0.1 m. Radio
waves are commonly used for audio
communications (i.e., for radios), but the term is
used for electromagnetic waves in this range
regardless of their application. Radio waves
typically result from an alternating current in
the wires of a broadcast antenna.
1. They cover a very broad wavelength range
and are divided into many subranges,
including microwaves, electromagnetic

31. Microwaves
The highest-frequency electromagnetic waves that can be
produced by currents in macroscopic circuits and devices.
Their high frequencies correspond to short wavelengths
compared with other radio waves hence the name
“microwave.” Microwaves also occur naturally as the cosmic
background radiation left over from the origin of the universe.
Along with other ranges of electromagnetic waves, they are
part of the radiation that any object above absolute zero
emits and absorbs because of thermal agitation, that is, from
the thermal motion of its atoms and molecules.
1. Most satellite-transmitted information is carried on
microwaves. Radar is a common application of microwaves.
2.
3. Other application includes: WiFi, Bluetooth and RFID (radio
frequency identification)
4.

32. Infrared Radiation “below red”
generally produced by thermal motion, and the
vibration and rotation of atoms and molecules.
Electronic transitions in atoms and molecules
can also produce infrared radiation. About half
of the solar energy arriving at Earth is in the
infrared region, with most of the rest in the
visible part of the spectrum.
Applications: Reconnaissance satellite, infrared
lamps and remote controls

33. Visible light
the narrow segment of the electromagnetic
spectrum between about and about to which
the normal human eye responds.
Red light has the lowest frequencies and longest
wavelengths, whereas violet has the highest
frequencies and shortest wavelengths.
Blackbody radiation from the Sun peaks in the
visible part of the spectrum but is more intense
in the red than in the violet, making the sun

34. Ultraviolet Radiation
Ultraviolet means “above violet.” The electromagnetic
frequencies of ultraviolet radiation (UV) extend upward from
violet, the highest-frequency visible light. The highest-
frequency ultraviolet overlaps with the lowest-frequency X-
rays. The wavelengths of ultraviolet extend from down to
about at its highest frequencies.
Low-intensity ultraviolet has applications such as providing
the energy to cause certain dyes to fluoresce and emit
visible light, for example, in printed money to display hidden
watermarks as counterfeit protection.

35. X-rays
have wavelengths from about to They have shorter
wavelengths, and higher frequencies, than ultraviolet, so that
the energy they transfer at an atomic level is greater.
The widest use of X-rays is for imaging objects that are opaque
to visible light, such as the human body or aircraft parts

36. Gamma Rays
The most penetrating nuclear radiation, the gamma ray, an
extremely high-frequency electromagnetic wave. Gamma rays
have characteristics identical to X-rays of the same frequency
—they differ only in source. The name “gamma rays” is
generally used for electromagnetic radiation emitted by a
nucleus, while X-rays are generally produced by bombarding a
target with energetic electrons in an X-ray tube. At higher
frequencies, gamma rays are more penetrating and more
damaging to living tissue.
They have many of the same uses as X-rays, including cancer
therapy. Gamma radiation from radioactive materials is used in
nuclear medicine