Loading presentation...

Present Remotely

Send the link below via email or IM

Copy

Present to your audience

Start remote presentation

  • Invited audience members will follow you as you navigate and present
  • People invited to a presentation do not need a Prezi account
  • This link expires 10 minutes after you close the presentation
  • A maximum of 30 users can follow your presentation
  • Learn more about this feature in our knowledge base article

Do you really want to delete this prezi?

Neither you, nor the coeditors you shared it with will be able to recover it again.

DeleteCancel

Make your likes visible on Facebook?

Connect your Facebook account to Prezi and let your likes appear on your timeline.
You can change this under Settings & Account at any time.

No, thanks

MODERN PHYSICS APPLICATION IN LIGHT

No description
by

nuraqilah mramli

on 6 April 2015

Comments (0)

Please log in to add your comment.

Report abuse

Transcript of MODERN PHYSICS APPLICATION IN LIGHT

X-RAY
MODERN PHYSICS APPLICATION IN LIGHT
Introduction to Light
NATURAL

From sun
Eg : UV light

ARTIFICIAL
Made by man
Eg : fluorescent, laser, halogen lamp, L.E.D, etc
Applications of Light
Medicine

Light therapy
X-ray

Household
Solar cell

Radar

Light Detection and Ranging (LiDAR)
INTRODUCTION
Classical
Modern
1800's
Mechanics, thermodynamics, electricity and magnetism, optics
1900's
Atomic and nuclear, quantum mechanics, particle Physics, condensed matter, relativity and cosmology
USES :
a way to treat seasonal affective disorder (SAD).
help with other types of depression and sleep disorder.
to increase the effectiveness of antidepressant medication.
HOW IS IT
DONE?
During light therapy sessions,you sit near or work near
PRECAUTIONS!
talk to a doctor for advice
look for a light therapy that emits as little UV light as possible
do not use tanning beds as an alternative in light therapy
RISKS :
eyestrain
headache
nausea
irritability or agitation
hyperactivity
PHOTOTHERAPY
SOLAR CELL
HOW SOLAR CELL WORKS?
Photons
(from sunlight) hit the solar panel
These
photons
are absorbed by semiconducting materials, e.g ; silicon.

Absorption of
photons
cause electrons to be excited from their current molecular/atomic orbital.

The excited electron may either dissipate energy as heat and return to its orbital OR travel through the cell until it reaches an electrode.

Current flows through the material to cancel the potential and this electricity is captured.

An array of solar cells converts solar energy into a usable amount of direct current (DC) electricity.

An inverter can convert the power to alternating current (AC).
ADVANTAGES
FOC – Free of charge

Doesn`t cause pollution

Can be used in remote areas where it is too expensive to extend the electricity power grid.

Many everyday items can be powered by solar energy
e.g : calculators

Renewable source
SOLAR CELL?
an
electrical device

which converts light energy directly into electricity.

this devise possesses electrical characteristics ;
- current
- voltage
- resistance

known as
photovoltaic device
(very sensitive to light) ; regardless whether it is sunlight or artificial light

used as
photodetectors
; to detect light or other electromagnetic radiation near the visible range or measuring light intensity.
e.g ; infrared detectors
DISADVANTAGES
... Building of machine and equipment are costly
… Manufacturing of these machine and equipment in factories cause pollution
… Large areas of land are required to capture the sun energy.
Solar power stations can be built but they do not match the power output of similar sized conventional power stations.
… Solar power charges batteries so that devices can be used at night. the batteries are large, heavy, need storage space, & need to be replaced from time to time.
... Can only be harnessed during daytime and sunny.
LiDAR
LIGHT DETECTION AND RANGING
remote sensing method used to examine the earth's surface

can be measured in 3 different ways:
HOW IS IT DONE?
LiDAR system records the time it takes for the light energy to travel to the ground and back
1. Airplane
3. Space
2. Ground
1. Airplane
uses a laser to scan the earth from side to side as the plane flies

ONLY use either green light (532nm) or near infrared light (1062nm) because they reflect strongly after vegetation
2. GPS Retriever
tracks the altitude and X,Y location of the airplane

allows us to figure out where LiDAR reflections are on the ground
3. IMU (Inertial Measurement Unit) System
tracks the tilt of the plane in the sky as it flies
4. Computer
records all the data that the LiDAR collects as it scans the earth's surface
PARTS OF LiDAR SYSTEM
Distance
= (Time travel x Speed of light) / 2
Ground Elevation
= Altitude - Distance
INTRODUCTION
X-ray and gamma ray are exactly same as the nature of light
X-ray and gamma ray have shorter wavelength than light
X-ray and gamma ray can penetrate materials that light cannot
HISTORY
For investigating the structure of matter
Generated about potential applications of rays as an aid in medicine and surgery
X-rays were used little outside the realms of medicine and dentistry
American Society of Mechanical Engineers (ASME) permitted X-ray approval of fusion welded pressure vessels
PRESENT
We still capture a shadow image on film using similar procedures and processes
Electronics and computers allow technicians to now capture images digitally
Technology has evolved allowing radiography to be widely used in numerous areas of inspection
Radiography industry to inspect not only welds and castings, but to radiographically
PROPERTIES OF X-RAY AND GAMMA RAY
Not detected by human senses
Travel in straight lines at the speed of light.
Cannot be changed by electrical or magnetic fields
Can be diffracted to a small degree
Degree of penetration depends on their energy
CONCLUSION
WHY WE USE MODERN PHYSICS?
Modern physics
provides a wider compared to classical physics.So,there are more accurate picture of behaviour of the universe.
Classical physics
is easier to understand and use so it remains valuable in several situasions.Its directly related to everyday experience.
There are many application of modern physics in light.For example in medicine, a light therapy (photoyherapy) is using for healing.It is a way to treat seasonal affective disorder (SAD) which is type of depression that occurs at a certain time each year usually in the fall or winter by exposure to artificial light.
The light therapy is very helpful to society especially society in UK and Ireland as they are more susceptible to SAD as they are situated in the higher latitudes of the northern hemisphere.
It shows that application of modern physics gives impact to the society and it proves that the important of physics in our daily life.
the system uses the speed of light to calculate the distance between the top of that object andplane
BENEFITS
can be used create map because of its high resolution and accuracy

able to predict canopy bulk density and canopy base height

a useful tools when designing and constructing new building
Full transcript