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WAVELENGTH MODULE
https://physics.info/waves/#:~:text=To%20propagate%20%2C%20in%20the%20sense,which%20a%20wave%20can%20propagate.
A wave is a propagating dynamic disturbance (change from
equilibrium) of one or more quantities in physics,
mathematics, and related subjects, commonly described by a
wave equation. At least two field quantities in the wave
medium are involved in physical waves. Periodic waves occur
when variables oscillate periodically around an equilibrium
(resting) value at a specific frequency. A traveling wave
occurs when the entire waveform moves in one direction; a
standing wave occurs when two superimposed periodic waves
move in opposite directions. The amplitude of vibration in a
standing wave features nulls at some points when the wave
amplitude seems reduced or even zero.
Wave
A wave is a disturbance in a medium that transports energy
without causing net particle movement. Elastic deformation,
pressure variations, electric or magnetic intensity, electric
potential, or temperature variations are all examples.
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Water waves (ripples of gravity waves, not
sound through water)
Light waves
S-wave earthquake waves
Stringed instruments
Torsion wave
A crest is the highest point of a transverse wave. It’s a trough
at the bottom.
2. Longitudinal Wave:
The movement of the particles in the medium in a longitudinal
wave is in the same dimension as the wave’s movement
direction.
Examples of longitudinal waves:
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Sound waves
P-type earthquake waves
Compression wave
Parts of longitudinal waves:
1.
2.
Compression-The particles are close together in this
case.
Rarefaction-Where the particles are dispersed
3. Electromagnetic Waves:
Figure
1. Pictorial representation of waves.
Characteristics of Waves
Waves include the following characteristics:
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The particles of the medium traversed by a wave
vibrate only slightly about their mean positions, but
they are not permanently displaced in the wave’s
propagation direction.
Along with or perpendicular to the wave’s line of
travel, each succeeding particle of the medium
performs a motion quite identical to its predecessors.
During wave motion, only energy is transferred, but
not a piece of the medium.
These are waves that are produced and propagated without the
use of a material medium, i.e., they can pass through vacuum
and any other material medium.
Examples of electromagnetic waves:
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visible light
ultra-violet light
radio waves
microwaves
Types of Waves
The several forms of waves are listed here:
1. Transverse Waves:
Figure 2. Electromagnetic waves.
Waves in which the medium moves at an angle to the wave’s
direction.
Examples of transverse waves:
4. Mechanical waves:
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Only a material medium can produce or propagate mechanical
waves. Newton’s equations of motion apply to these waves.
Examples of mechanical waves:
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waves on water surface
waves on strings
sound waves
Mechanical waves are of two types:
1.
2.
Transverse wave motion- The particles of the
medium vibrate at right angles to the wave’s
propagation direction in transverse waves. Transverse
waves include string waves, surface water waves, and
electromagnetic waves. The disturbance that travels
in electromagnetic waves (which include light waves)
is caused by the oscillation of electric and magnetic
fields at right angles to the wave’s travel direction.
Longitudinal wave motion- Particles in the medium
vibrate back and forth around their mean location
along the energy propagation direction in these sorts
of waves. They’re also known as pressure waves.
Longitudinal mechanical waves are what sound
waves are.
Frequency – The number of waves passing a spot in
a certain amount of time is referred to as the
frequency of a wave. The hertz (Hz) unit of
frequency measures one wave every second.
The frequency’s reciprocal is the period, and vice versa.
Period=1 / Frequency
OR
Frequency = 1 / Period
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Speed – The speed of an object refers to how quickly
it moves and is usually stated as the distance traveled
divided by the time it takes to travel. The distance
traveled by a specific point on the wave (crest) in a
given amount of time is referred to as the wave’s
speed. A wave’s speed is thus measured in meters per
second or m/s.
Sample Problems
5. Matter waves:
Problem 1: In a specific medium, a wave travels at 900
meters per second. Calculate the wavelength of a specific
point in the medium if 3000 waves pass through it in 2
minutes.
These waves are linked to the movement of matter particles.
Solution:
Examples of matter waves:
The speed of a wave in medium v = 900 ms-1
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electrons
protons
neutrons
Formula for Speed of Wave
It’s the entire distance a wave travels in a particular amount of
time. The formula for calculating wave speed is as follows:
Wave Speed = Distance Covered/Time taken
Properties of Waves
The following are the primary characteristics of waves:
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Amplitude – A wave is a form of energy
transmission. The amplitude of a wave is its height,
which is commonly measured in meters. It is
proportional to the quantity of energy transported by
a wave.
Wavelength – A wavelength is a distance between
identical locations in adjacent cycles of crests of a
wave. In addition, it is measured in meters.
Period – A wave’s period is the amount of time it
takes a particle on a medium to complete one
complete vibrational cycle. Because the period is a
unit of time, it is measured in seconds or minutes.
Freq. of wave = no. of waves passing per sec (n) = 3000
waves/2 min = 3000 / 2 × 60 = 25 s
Wave length (λ) = ?
v = n × (λ)
λ = v/n
= 900/25
= 36 m
Problem 2: What distinguishes the roar of our national
animal from that of a mosquito?
Solution:
The buzzing of a mosquito creates a sound of high pitch and
low intensity or loudness, but the roaring of a national animal
(tiger) produces a sound of low pitch and high intensity or
loudness.
Problem 3: Is it feasible to tell when a vessel maintained
beneath the faucet is going to overflow?
Solution:
The length of an air column is inversely related to the
frequency of the note it produces. The length of the air column
above the vessel reduces as the level of water in the vessel
rises. It generates a sound with a decreasing frequency, i.e. the
sound gets shorter. It is possible to determine whether the
vessel is filled with water based on the shrillness of the sound.
Problem 4: The bottom of a ship in the sea shoots SONAR
waves straight down into the saltwater. After 3.5 s, the
signal reflects off the deep bottom bedrock and returns to
the ship. When the ship reaches 100 km, it transmits
another signal, which is received after 2 s. Calculate the
depth of the sea in each example, as well as the height
difference between the two.
Solution:
Velocity of SONAR waves in water C = 1500 ms-1
Time taken by be wave after reflection from the bottom of sea
2t = 3.5s
REPORT 1: STANDING WAVES
What is a standing waves?
- Standing waves are formed by the superposition of
two travelling waves of the same frequency (with the
same polarisation and the same amplitude) travelling
in opposite directions.
- The animation depicts two waves moving through a
medium in opposite directions. As is the case in any
situation in which two waves meet while moving
along the same medium, interference occurs. The two
waves interfere to form a new wave pattern known as
the resultant. The resultant in the animation below is
shown in black. The resultant is merely the result of
the two individual waves added together in
accordance with the principle of superposition.
- Standing waves are called standing waves because
they look stationary, hence the word ‘standing’.
What are nodes and antinodes?
- Antinodes are points on a stationary wave that
oscillate with maximum amplitude. Nodes are points
of zero amplitude and appear to be fixed.
- NODES for no displacement
- ANTINODES for displacement (movement)
t =1.75s
Distance covered (d) = ?
C = d/t => d = c.t = 1500 × 1.75 – 2625 m
After moving 100km
The time taken by the wave = 2t = 2s
T = 2/2 = 1s
d =?
d = 1500 × l
= 1500
The difference between these two heights = 2625 – 1500
= 1125m
Problem 5: Why does a tone sound louder in an empty
room than in a room with furniture and other objects?
Solution:
Sound is an energy form. The majority of the energy is
absorbed by the furniture that acts as an obstruction. As a
result, the strength of sound decreases, yet in an empty room,
the intensity of sound remains relatively constant due to the
absence of impediments, and we perceive it as louder.
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Nodes are points of no displacement. Antinodes
oscillate between large negative and positive
displacement.
How are standing waves formed?
- Standing waves are produced whenever two waves of
identical frequency interfere with one another while
traveling opposite directions along the same medium.
Examples (everyday formation of standing waves)
- One easy example to understand standing waves is
two people shaking either end of a jump rope. If they
shake in sync the rope can form a regular pattern of
waves oscillating up and down, with stationary points
along the rope where the rope is almost still (nodes)
and points where the arc of the rope is maximum
(antinodes).
- Acoustic guitar
- The fixed strings of the guitar act as a
medium
- Whistling
- Here, the air acts as a medium
- Flute
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The body of the flute acts as a contained
medium
REPORT 2: RESONANCE
Definition
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A phenomenon in which an external force or a
vibrating system forces another system around it to
vibrate with greater amplitude at a specified
frequency of operation.
Resonance occurs when the matching vibrations of
another object increase the amplitude of an object’s
oscillations.
Examples
- Music instrument
- Swing
- Bridge
Types of resonance
1. Mechanical resonance
- Mechanical resonance occurs in physical systems
with mass and elasticity, such as mechanical
structures, musical instruments, or even bridges.
When an external force is applied at the natural
frequency of the system, it can cause the system to
vibrate with increasing amplitude, which can lead to
mechanical failure if not controlled.
- EX. A swing in a playground can exhibit mechanical
resonance. When you push the swing at the right
frequency, it starts swinging more and more with
each push. This is because the frequency of your
pushes matches the natural frequency of the swing.
2.
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3.
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Acoustic resonance
Acoustic resonance is a specific type of mechanical
resonance that occurs in sound waves. When an
object or cavity vibrates at its natural frequency, it
can produce and amplify sound waves of that same
frequency. This phenomenon is responsible for the
production of music in musical instruments like
stringed instruments, wind instruments, and the
resonance of sound in enclosed spaces like concert
halls.
EX. Musical instruments like a guitar or a violin rely
on acoustic resonance. When you pluck a guitar
string, it vibrates at its natural frequency, producing a
specific musical note due to the resonance within the
instrument's body.
Electrical resonance
Electrical resonance occurs in electrical circuits
containing inductors, capacitors, and resistors. When
the frequency of an alternating current (AC) source
matches the natural resonant frequency of the circuit,
it can lead to a significant increase in current or
voltage. This phenomenon is used in various
applications, including in radio tuning circuits and
inductively coupled plasma (ICP) spectroscopy.
EX. A common example is the tuning circuit in a
radio. The LC (inductor-capacitor) circuit in the radio
tuner resonates at the desired radio frequency. When
the circuit is tuned to the correct frequency, it allows
the radio to pick up the desired station by amplifying
its signal while rejecting others.
REPORT 3: BEAT
What is beat?
- Beat is a rhythmic pulsation that can be heard when
two sound waves with slightly different frequencies
are played together. It is created by the interference
pattern between the two waves, which causes the
amplitude of the resulting wave to oscillate at a
frequency equal to the difference between the
frequencies of the original waves.
- In other words, beat occurs when two sound waves
are out of phase with each other, causing them to
alternately reinforce and cancel each other out. This
creates a distinctive rhythmic pattern that can be
heard as a pulsing or throbbing sound.
Examples of beat
Creating rhythm and pulse
- Beat is a fundamental element of music that helps to
create rhythm and pulse in songs. It provides a
consistent underlying structure that allows listeners to
tap their feet or dance along to the music.
Drumming
- In many genres of music, the drummer plays a crucial
role in establishing and maintaining the beat. They
often use a variety of techniques, such as syncopation
and accenting, to create interesting and dynamic
rhythms.
Electronic music production
- In electronic music production, beat is often created
using software and digital instruments. Producers can
manipulate the timing, velocity, and sound of each
beat to create a unique and complex rhythm.
The physics of sound and beat creation
Sound oscillation and brain activity
- Sound is created by the vibration of an object, which
causes pressure waves in the air that our ears perceive
as sound. These pressure waves are known as sound
waves and can be analyzed in terms of their
frequency and amplitude.
- When two sound waves with slightly different
frequencies overlap, they create a beat, which is a
periodic variation in the amplitude of the sound
wave. This beat can be heard as a pulsing or
throbbing sound.
- Research has shown that listening to beats with a
frequency of around 10 Hz can entrain brain activity
to a similar frequency, resulting in a relaxed or
meditative state. This phenomenon is known as
brainwave entrainment and has been studied for its
potential therapeutic benefits.
Analysis on sound oscillation and brain activity
- Sound waves are created by the vibration of an object
that travels through a medium such as air or water.
These vibrations cause pressure changes in the
medium which our ears perceive as sound. Sound can
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be analyzed in terms of its frequency, amplitude, and
wavelength. The frequency of a sound wave is
measured in Hertz (Hz) and determines the pitch of
the sound. Amplitude is the measure of the strength
of the sound wave and determines the volume of the
sound. Wavelength is the distance between two
consecutive points on a sound wave that are in phase.
When we hear a beat, it is actually the result of the
brain processing two sound waves with slightly
different frequencies. This phenomenon is known as
binaural beats. When these two sound waves are
presented to each ear separately, the brain processes
them and produces a third tone which is the
difference between the two frequencies. This third
tone is what we perceive as the beat. Research has
shown that exposure to binaural beats can have a
positive effect on cognitive performance and mood.
The mathematics of beat
- When two sound waves with slightly different
frequencies are played simultaneously, they create a
phenomenon called beat. The frequency of the beat is
equal to the difference between the frequencies of the
two original waves. For example, if one wave has a
frequency of 440 Hz and another has a frequency of
442 Hz, the beat frequency will be 2 Hz.
- The formula for calculating beat frequency is simply
the absolute value of the difference between the
frequencies of the two waves. This can be expressed
as: f_beat = |f1 - f2|. It's important to note that the
amplitude of the beat is determined by the difference
in amplitude between the two original waves. The
greater the difference, the louder the beat will be.
Musical applications
- In music, beat is the underlying pulse or rhythm that
drives a song forward. It's what makes you tap your
foot or nod your head along to the music. Without
beat, music would feel stagnant and lifeless.
- One example of a song that utilizes beat is "Billie
Jean" by Michael Jackson. The iconic drumbeat in
the song creates a sense of urgency and excitement,
driving the melody forward. Another example is
"Stayin' Alive" by the Bee Gees. The disco beat in
this song is so infectious that it's almost impossible
not to dance along.
Practical application
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One practical application of beat is in tuning musical
instruments. When two notes played simultaneously
are slightly out of tune, a beating sound can be heard.
By adjusting the tuning of one of the notes, the beat
frequency can be eliminated, resulting in a more
harmonious sound.
Another practical application of beat is in speech
therapy. People who stutter or have difficulty with
rhythm and timing in their speech can benefit from
practicing with a metronome or other beat-keeping
device. This can help improve their fluency and
overall communication skills.
Conclusion
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In conclusion, we have explored the fascinating
world of acoustics and the physics of sound. We have
learned what beat is and how it is created, delved into
the mathematics behind it, and examined its
applications in both music and practical settings.
Understanding the physics of sound and how it
relates to beat is crucial not only for musicians and
audio engineers but also for anyone interested in
speech therapy or tuning instruments. By grasping
these concepts, we can better appreciate the
intricacies of the sounds around us and even improve
our own auditory experiences.
So let us continue to explore and learn about the
science of sound, for as physicist and musician Albert
Einstein once said, "The most beautiful thing we can
experience is the mysterious. It is the source of all
true art and all science."
REPORT 4: NATURE OF LIGHT
What is Light?
- Light is a form of energy that allows you to see the
things around you.
- Light is basic to almost all life on Earth.
- Light is a form of electromagnetic radiation.
How does light allow you to see things?
- Light travels away from its source in straight lines.
When it hits an object, it reflects (bounces off) and
travels in a new direction. If the reflected light enters
your eyes, you can see the object.
Sources of Light:
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All light comes from a luminous source. While
non-luminous objects do not emit light but may
reflect or transmit light from other sources.
Whether, its natural or artificial.
Materials
Materials can indeed be classified based on how they
respond to light incident on them. This classification typically
involves three main categories.
How does light travel?
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LIGHT TRAVELS IN STRAIGHT LINES.
When you shine a flashlight or torch at night, you can
see those light travels in a straight path.
LIGHT TRAVELS EXTREMELY FAST.
It travels at the speed of 186,000 miles or 299,792
kilometers per second in a vacuum. A vacuum is an
empty space so there is nothing that stops light from
traveling.
What are the 6 properties of light?
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Reflection of Light
This property involves the bouncing back of light
when it encounters a surface. The angle at which light strikes
the surface is equal to the angle at which it is reflected.
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Property: Reflection is the bouncing back of light
waves when they encounter a surface.
Example: A mirror reflects light, allowing you to see
your own reflection.
Refraction of Light
Refraction is the bending of light as it passes from
one medium into another, due to a change in its speed.
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Property: Refraction is the bending of light as it
passes from one medium into another, due to a
change in its speed.
Example: When light passes from air into water, it
bends, causing objects underwater to appear shifted
from their actual position.
Dispersion of Light
Dispersion is the separation of light into its
constituent colors (spectrum) based on the different
wavelengths, resulting in a rainbow effect.
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Property: Dispersion is the separation of light into its
constituent colors (spectrum) based on the different
wavelengths, resulting in a rainbow effect.
Example: When white light passes through a prism, it
separates into a spectrum of colors, as seen in a
rainbow.
Diffraction of Light
Diffraction is the bending of light waves around
obstacles or through narrow openings, causing them to spread
out.
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Property: Diffraction is the bending of light waves
around obstacles or through narrow openings,
causing them to spread out.
Example: When light passes through a narrow slit, it
diffracts, creating a pattern of light and dark bands on
the other side.
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Polarizing sunglasses reduce this reflection, known as
glare.
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Interference of Light
Interference occurs when two or more light waves
overlap and combine, either constructively (amplifying) or
destructively (canceling) each other.
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Property: Interference occurs when two or more light
waves overlap and combine, either constructively
(amplifying) or destructively (canceling) each other.
Example: In a soap bubble, interference between the
incoming and reflected light waves creates the
colorful patterns observed on its surface.
Interference in soap bubbles occurs when light waves
interact with each other as they pass through the thin film of
soap solution that makes up the bubble's surface. When light
from the sun or another light source hits the soap bubble, some
of the light is reflected from the outer surface of the bubble,
and some enters the bubble and is then reflected back from the
inner surface.
These two sets of reflected light waves can either
reinforce each other (constructive interference) or cancel each
other out (destructive interference), depending on their relative
phases. This interference creates the beautiful and colorful
patterns you often see on soap bubbles. The colors change as
the thickness of the soap film changes, causing variations in
the path lengths of the reflected light waves and, consequently,
changes in the interference patterns and colors observed. This
colorful phenomenon is a result of the interference of light
waves and is a great example of the wave nature of light.
These properties of light are fundamental in
understanding its behavior and are utilized in various
applications, from everyday phenomena like mirrors and
rainbows to advanced technologies such as fiber optics and
lasers.
REPORT 5: ELECTROMAGNETIC SPECTRUM
Colors of Light
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Polarization of Light
Polarization refers to the orientation of the
oscillations of light waves in a specific direction, restricting
the vibration to a single plane.
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Property: Polarization refers to the orientation of the
oscillations of light waves in a specific direction,
restricting the vibration to a single plane.
Example: Polarized sunglasses use filters to block
light waves vibrating in certain directions, reducing
glare from surfaces like water or roads.
Polarized lenses have a special chemical applied to
them to filter light. The chemical's molecules are
lined up specifically to block some of the light from
passing through the lens.
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Light is made up of wavelengths of light, and each
wavelength is a particular color. The color we see is a
result of which wavelengths are reflected back to our
eyes.
The color of light is determined by its wavelength.
When white light, which contains all visible wavelengths,
passes through a prism or a diffraction grating, it
separates into its component colors, creating a spectrum.
Electromagnetic Spectrum
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The electromagnetic spectrum is the continuum of all
electromagnetic waves, which are transverse waves
composed of oscillating electric and magnetic fields
propagating through space.
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These waves do not require a medium and can travel
through a vacuum. The spectrum includes a vast
range of wavelengths and frequencies, from the
longest radio waves to the shortest gamma rays.
The electromagnetic spectrum is divided into separate
bands, and the electromagnetic waves within each
frequency band are called by different names.
The different types of electromagnetic radiation that
make up the electromagnetic spectrum.
Key Components of the Electromagnetic Spectrum:
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Radio Waves: Radio waves have the longest
wavelengths in the spectrum, ranging from several
millimeters to hundreds of meters. They are used in
radio broadcasting, wireless communication, and
radar systems.
Radio waves are also emitted by stars and gasses in
space.
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Microwaves: Microwaves have shorter wavelengths
than radio waves, typically between a millimeter and
a meter. They are used in microwave ovens, satellite
communication, and certain wireless technologies.
Infrared (IR) Radiation: Infrared radiation lies just
beyond the visible spectrum, with wavelengths
ranging from about 750 nanometers to 1 millimeter. It
is used in heat sensing, remote controls, and infrared
photography.
Night vision goggles pick up the infrared light
emitted by our skin and objects with heat. In space,
infrared light helps us map the dust between stars.
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Visible Light: Visible light is the portion of the
spectrum that is visible to the human eye. It ranges
from approximately 380 nanometers (violet) to 750
nanometers (red) and consists of various colors.
Visible light may be a tiny part of the electromagnetic
spectrum, but there are still many variations of
wavelengths. We see these variations as colors.
On one end of the spectrum is red light, with the
longest wavelength. Violet light has the shortest
wavelength. White light is a combination of all colors
in the color spectrum. It has all the colors of the
rainbow.
The colors of the visible light spectrum can be
remembered by the mnemonic "Roy G Biv" for red,
orange, yellow, green, blue, indigo, and violet.
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Ultraviolet (UV) Radiation: UV radiation has shorter
wavelengths than visible light, ranging from 10 to
400 nanometers. It has applications in disinfection,
forensics, and astronomy.
Ultraviolet radiation is emitted by the Sun and are the
reason skin tans and burns. "Hot" objects in space emit
UV radiation as well. UV energies are too high for human
eyes to see. UV light traces the hot glow of stellar
nurseries and is used to identify the hottest, most
energetic stars.
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X-Rays: X-rays have very short wavelengths,
typically between 0.01 to 10 nanometers. They are
used extensively in medical imaging, materials
analysis, and airport security.
X-rays come from the hottest gas that contains atoms.
They are emitted from superheated material
spiraling around a black hole, seething neutron stars, or clouds
of gas heated to millions of degrees. A dentist uses X-rays to
image your teeth, and airport security uses them to see through
your bag. Hot gasses in the Universe also emit X-rays.
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Gamma Rays: Gamma rays have the shortest
wavelengths and highest frequencies in the spectrum,
measuring less than 0.01 nanometers. They are
produced in nuclear reactions and are used in cancer
treatment and astrophysics.
Gamma rays have the highest energies and shortest
wavelengths on the electromagnetic spectrum. They come
from free electrons and stripped atomic nuclei accelerated by
powerful magnetic fields in exploding stars, colliding neutron
stars, and supermassive black holes.
Ionizing Radiation
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Energy Levels: Ionizing radiation has very high
energy levels
Examples: Types of ionizing radiation include
X-rays, gamma rays, and certain particles like alpha
and beta particles.
Effect on Matter: Ionizing radiation can ionize atoms
and molecules by stripping away tightly bound
electrons, creating charged ions. This can damage or
alter the chemical structure of materials and
biological tissues.
Health Risks: Exposure to ionizing radiation carries
health risks, including an increased risk of cancer and
damage to DNA.
Non-Ionizing Radiation
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Energy Levels: Non-ionizing radiation has lower
energy levels, with longer wavelengths compared to
ionizing radiation.
Examples: Types of non-ionizing radiation include
visible light, infrared (IR), UV rays, microwaves, and
radio waves.
Effect on Matter: Non-ionizing radiation does not
have enough energy to ionize atoms or molecules. It
can, however, cause heating effects when absorbed
by materials (e.g., microwave ovens heat food).
Health Risks: Non-ionizing radiation is generally
considered safe at typical exposure levels.
Significance and Applications
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Communication
Medicine
Scientific Research
Consumer Electronics
Security and Defense
Technological Innovation
Exploration of the Universe
REPORT 6: REFLECTION
Geometric Optics
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Our lives are filled with light.
light can evoke spiritual emotions.
Life itself could not exist without light’s energy.
Optics is the branch of physics that deals with the
behavior of visible light and other electromagnetic
waves.
It has two major parts based on the size of objects
that light encounters: geometric optics, which deals
with interactions with objects that are larger than the
light's wavelength, and wave optics, which deals with
interactions with smaller objects.
Ray Aspect of Light
1.
2.
3.
Light reaches the upper atmosphere of Earth traveling
through empty space directly from the source.
Light can travel through various media, such as air
and glass, to the person.
Light can also arrive after being reflected, such as by
a mirror.
Two laws govern how light changes direction when it interacts
with matter:
1.
2.
Law of reflection, for situations in which light
bounces off matter.
Law of refraction, for situations in which light passes
through matter.
Law of Reflection
Whenever we look into a mirror, or squint at sunlight
glinting from a lake, we are seeing a reflection. Large
telescopes use reflection to form an image of stars and other
astronomical objects.
The law of reflection shows how the angles are
measured relative to the perpendicular to the surface at the
point where the light ray strikes.
Key Components of Reflection
1. Incident Ray
2. Refracted Ray
3. Normal Line
4. Angle of Incidence (i)
5. Angle of Refraction (r)
From a less dense to a denser medium
example: from air to glass
From a denser to a less dense medium
example: from water to air
Refraction in Water
- Light rays change direction at the surface of the
water.
- The image of the chest appears to be more shallow
than the actual chest
Refraction of Light
If ray of light enters from rare into denser medium it bends
towards the normal. But when it enters from denser into rare
medium it bends away from normal
Practical Application of Refraction
Optics: Lenses, such as those in eyeglasses or cameras, rely on
refraction to focus light and correct vision or capture images.
Astronomy: Refraction by Earth's atmosphere affects the
apparent position of celestial objects, leading to phenomena
like atmospheric dispersion and the Green Flash.
Prism Spectroscopy: Prisms use refraction to disperse light
into its constituent colors, enabling the study of spectra and
the identification of elements in stars.
Mirage Formation: Refraction of light in the Earth's
atmosphere causes mirages, where distant objects appear
distorted or displaced.
Underwater Vision: Snorkelers and divers experience
refraction when light passes from water into air, making
objects underwater appear closer and larger than they are
REPORT 8: PLANE MIRRORS
REPORT 9: SPHERICAL MIRRORS
REPORT 7: REFRACTION
What is Refraction?
- The bending of light rays as they pass between two
different media
- Refraction occurs due to changes in speed of light in
different mediums
- Different media slow down light by different amounts
the more that light slows down, the more the light is
refracted.