Scope and Career Opportunities through Physics
School Science 49 (2) March 2011
A.
K. Mody.
Department of Physics,
VES College of Arts, Science
and Commerce,
Sindhi Society, Chembur,
Mumbai 400 071
atul_mody@rediffmail.com
Abstract: This article discusses what
Physics encompasses as a subject up to +2 level and application it can lead to
as one pursue the same beyond +2 level. It also touches upon career
opportunities available to Physics Graduates. The purpose of the article is to
illustrate for students of +2 Science stream and physics undergraduate
students, possible opportunities which physics offers as a discipline and also
to motivate undergraduate physics students who may otherwise be pursuing
graduation in absence of any (so called) better opportunity, just for sake of
graduation, a most likely contemporary scenario.
Physics is broadly classified
into mechanics, heat and thermodynamics, waves, optics, electromagnetism and
modern physics as taught up to +2 level in present system. One often encounters
a phenomenon that deals with more than one of these areas simultaneously. In
this article we want to see what are the different phenomena and applications
physics deals with. Many of the phenomena that are discussed in this article
may require one to go beyond the +2 level techniques though fundamental
principles remain mostly same. Therefore it becomes important to go through
scope to appreciate importance of the subject.
Primary objective of mechanics is
to deal with motion, different laws that govern motion, cause and effect. Well,
cause and effect is at the foundation of any science. Mechanics tries to
understand motion in terms of Newton’s laws and conservation principles. For
this it defines and deals with physical quantities like position, momentum,
force, energy etc….
Laws of
mechanics are used to understand what happens in sports: e.g., in cricket:
spin, swing, trajectory while throwing and similarly in football, base ball
etc… Well-known scientist Hemholtz used analogy of a pump to explain mechanism
of heart. As students learn: motion is
possible only due to action reaction forces (for example that of rockets) and
friction (in day to day life). Understanding centre of mass and motion of and
around centre of mass are very important for machines and structures. It is
important to give thought to how boomerang works, how we balance our self or
how animals use their tail while in different state of motion. The recent
Hollywood animation film ‘Avatar’ shows tails of aliens fairly
accurately. One must note here that stunt sequences in Hindi films are
often unrealistic from the point of view of Physics.
Study of motion
of projectiles is important from the point of view of sports, launching
missiles and firing rockets. This also requires rotational motion of earth to
be taken into consideration (Using pseudo force called Coriolis force).
Coriolis force is useful in understanding cyclones, water currents, whirlpools
and weather pattern. Circular and rotational motions cover wide range of
interesting areas. These include design of curved roads and racetracks, motion
of divers and ice skaters, and balancing in different parts of machines that
uses motors. Gyroscopes are used in navigation for ships, planes and automatic
guiding systems, including missiles.
Interaction
between two different objects in motion is a useful study from the point of
view of indoor games like carom, billiards to guiding planetary probes using
gravity of a planet (as in case of pioneer and voyager) and scattering of
elementary particle. One such experiment by Rutherford in late 19th
century of scattering of alpha particles by Gold foil lead to understanding of
atomic structure and latest LHC to understand mysteries of fundamental force
and origin of universe.
Study of simple
oscillation turns out to be useful in understanding of vibration of different
structures, machines to acoustics. At molecular level, using quantum nature of
the world one can understand properties of material and design new materials.
Motion in
presence of gravitational field applies to motion of planets and satellites, to
galaxies and launching of man-made satellites. Understanding gravitation in
finer detail is important for GPS (Geo-positioning system) to mobile
communication. Satellites not only have application for communication and military
purpose but also for spying for economic benefits in this globalised economy.
Most of these are taken for granted by present generation students.
Understanding of
sound/mechanical waves are not only important for musical instruments but
extends to acoustic design of auditorium, to ultrasonic for medical diagnosis,
to Doppler radar for prediction of calamities like tsunami, weather forecasting
and use by traffic police for measuring speed of vehicles. Different types of
waves generated during earthquake allow to locate its epicenter from any where
on the earth.
Study of
elasticity is useful in structural strength and design, to designing strong
materials for various applications.
Understanding
properties of fluids has an interesting event in the life of Archimedes. This
is of course related to loss of weight or floating objects. Surface tension is
important in plants, detergent and it has also been used in understanding of
nuclear property in liquid drop model. Change in melting and boiling point of
liquid with impurity has interesting application in freezing mixtures,
anti-freeze solvents, to cooking food. Other than static fluid it is extremely
interesting to understand fluids in motion. This has application in sports
(remember reverse swing in Cricket), generation of wind power, aerodynamic
design of simple automobiles to aeroplanes and space launch vehicles, flow of
blood in veins to flow of fluids through different systems in plants and those
in machines like automobile engines. Magneto-hydrodynamics is an important
branch in astrophysics and is also useful in controlling plasma especially for
controlled fusion reaction. Computational fluid dynamics has turned out to be
extremely rewarding branch with variety of applications.
Thermal properties of substances
have their roots in motion of atoms and molecules. We have made sufficient
progress to control and manipulate these properties to use it for our benefit.
Expansion properties of metals are used in bimetallic strip of starters, that
of liquids are used in simple thermometers and that of gases have been used for
example in storage of liquid petroleum gas for house hold cooking purpose.
Refrigerators, water heaters, air conditioners are also similar examples. These
properties and laws also help us understand and predict weather patterns and
understand effect of pollution on weather conditions. Changing properties of
substances as melting point using salt (to melt snow) or boiling point using
pressure (as in pressure cooker), antifreeze in lubricants and fuels are such
examples. Understanding the relationship between various parameters also helps
in designing new materials with designed properties. Invention of heat engine
has changed the history and geography of mankind.
Thermal conductivity helps us designing
engines and other materials. As an example copper bottom vessels have been
designed keeping in mind high conductivity of copper. Understanding convection
is useful in understanding climatic changes, ocean currents, weather pattern
etc. As a simple application, one needs to understand need of intermitten stirring when heated using
microwave as compared to traditional cooking on stoves.
Black body
radiation curve matches with spectrum from (i) tungsten filament (ii) Sun (iii) nuclear explosion (iv) any type of
flame and (v) microwave background radiation. Colour and brightness are related
to temperature by Wien’s law (lmT = 0.29 cm oK ). This has direct
application in Colour Physics. Understanding of black body radiation curve has
also allowed understanding of evolution of universe.
Thermodynamics
deals with macroscopic properties of fluids that can be understood as due to
collective behaviour of »1026 molecules.
This is understood in terms of kinetic theory of matter and its success is direct
evidence of atomicity.
Study of
behaviour of Specific heat has led to discovery of super-conductivity-fluidity.
It helps understanding climate of Mumbai (island city) as compared to other
inland cities in terms of high specific heat of water. Discontinuity in
specific heat of H2 is direct evidence of quantisation and
equipartition of energy. It is also an evidence of rotation and vibration of
molecules.
Low temperature physics involves
thermodynamics of molecular and nuclear magnetic systems. Possibility is seen
of manipulating atoms in a phenomenon called Bose-Einstein condensation at nano
Kelvin temperature that can help develop exotic materials.
Thermodynamics is used in design
of internal combustion engines, conventional and nuclear power plants,
Propulsion system for rockets, missiles, aircraft, ships and land vehicles. It
helps in designing fuel efficient, energy/cost saving systems.
Thermodynamic principles are also
applied to communication and information theory, and to chemical and biological
systems. In the latest development, Einstein’s General relativity is viewed as
thermodynamic limit of statistical theory with atoms of space-time being the
microscopic constituents.
Optics deals with light in two
ways. One, its propagation through different media, what is known as
geometrical optics; and Second, physics of its interaction with itself and to
different configuration of optical devices, known as physical optics. Lenses,
camera, microscopes, telescopes etc. are devices that work on these
principles. Diffraction,
interference and polarization are the physical phenomena involved in
interaction of light that helps us understand molecular and crystal structures. LASER has its application in
medicine, surgery, defence, entertainment etc… LASERs also have found their way
into our homes through CD/DVD players.
Electricity has been blessing and
at the same time has been a problem for production to meet its demand.
Electromagnetic waves are used in microwave range for cooking as well as for
telecommunication. They are also used in missile and rocket guiding systems.
Magnets and electromagnets have found their way into speakers, magnetic door
catchers and in medical applications. Photocopiers, smoke precipitators,
electric shockguns are a few common examples where principles of
electromagnetic theory are used.
Progress in communication has
been possible due to understanding of production, propagation and detection of
waves of different kinds. One needs to understand various parameters of wave
which are involved and how they are related. Today we are able to talk
across continents using mobile phones,
know our position with geopositioning system (GPS) and transfer large amount of
data using internet which may use wireless or optical cable transmission.
Electromagnetic waves in
different domains are used for various applications. Radio waves are used for
telecommunication and navigation. Microwaves are used for cooking, mobile links
and telecommunications. Infra-red are used in sensors, imaging, night vision
etc. Visible range is the one to which our eyes are sensitive. X- rays are used
for study of crystal structures, security systems, medical application and even
detecting cracks in the rocks. Gamma rays are used for radiation therapy to
treat disease like cancer.
Laws of physics
are different in the domain of atoms and molecules. The atomic world exhibits
quantum nature. It is our understanding of these laws that allowed us to
manipulate crystal structures to reach present stage of development of
electronics, which has revolutionized quality of our life. Attempts are being
made to manipulate atoms to reach power of tera-flop computers.
Photosynthesis
and response of eye are based on photoelectric effect. Spin flip transition of
outermost electron of Cs133 is used to calibrate 1 second. This is
what we call atomic standard clock. Wave nature of electron beam is used in
electron microscope to view substance at micrometer level. Scanning Tunneling
Microscope (STM) and Atomic Force Microscope (AFM) are based on quantum
tunneling effect and are used to observe at atomic level and study biological
processes respectively.
Study of matter
at nuclear dimensions exhibit two new types of forces, namely, strong and weak
nuclear force. Strong nuclear force has direct relation to nuclear energy,
which has civilian as well as military use. Weak force holds keys to some of
the cosmic mysteries that we are trying to understand through experiments like
large hadron colliders (LHC).
Description of
scope of physics as discussed above is suggestive and not exhaustive and one
can add many such examples.
Purpose of any
physics course/curriculum would be to introduce students to these phenomenon
and laws governing them. Expectations from any physics graduate would be that
s/he would be capable to take these human legacies further. This requires
students to have grasped the basic concepts well enough and acquired necessary
skills involved to be able to contribute.
The
processes one has to deal with at frontier level are too complex and involves
large number of phenomena to be addressed simultaneously. Any physics course
should aim at giving flavour and necessary competence to students so that they
become capable to contribute to the society.
What a
physics graduate need to do is identify the area of interest and then develop
extraordinary skill in that area along with capability in physics by the time
they graduate. Many extraordinary career options are available to students who
would like to pursue physics at frontier level as career. In the preceding
paragraphs, applications described also gives indication of possible areas
available for one to contribute. A professional physicist is expected to invent
new physics, study new phenomenon, understand new processes and develop new
applications for the benefit of mankind.
However
those who do not want to be a researcher also can have excellent career
opportunities after becoming physics graduate. Physics learned in the right
spirit develops analytical abilities which are very useful in those career
which look for such abilities rather than background training in a specific
area. Software development, data analysis in knowledge industry (financial
services), banking and management etc… are good examples of this. One may need
to do post graduation in these specific subjects like MBA,MCA etc... In
industry like software, physics graduates are much valued manpower due to
analytical abilities they acquire while doing their graduation. In fact game
physics has emerged as an important area which is important for those
developing computer games and programmes like driving and flight simulation.
Teaching
is another area where physics graduates and post graduates are expected to have
extra-ordinary career in time to come due to Information and Communication
Technology based education that is likely to take over.
Government
services like public service (like IAS, IPS…) and allied services like banking,
railways and public sector companies do recruit physics graduates and post
graduates. All these jobs require people with good analytical and problem
solving abilities and not merely those who have passed their exams. Students
who are careful in preparing themselves through physics can have a career
equally challenging, rewarding, and satisfying as any engineer, doctor or any
other professional. Most of those who have done B.Sc. Physics are found with
very successful career in one of those fields described above. All what is
required from students is focus on the career that they would want to pursue as
a physics graduate. Success is bound to follow.
