ppt

1. PHYSICS I 15-10248
Dominado , Jerick Brent D. Monday-Thursday
BSIT 2-2 5:30 - 7:00
1st Semester PB306
Doc. Randy M. Estigoy
 PHYSICS
The word physics has been derived from the Latin word physica, which means
natural thing. Though, there are many definitions of physics, yet it can be defined
as “The study of the properties of matter, energy and their mutual relationship is
called physics.” According to Microsoft Encarta, “Physics, major science, dealing
with the fundamental constituents of the universe, the forces they exert on one
another, and the results produced by these forces. Sometimes in modern physics
a more sophisticated approach is taken that incorporates elements of the three
areas listed above; it relates to the laws of symmetry and conservation, such as
those pertaining to energy, momentum, charge, and parity.” It means that physics
is the branch of science, which deals with the properties of matter and emery and
the relationship between them. It also tries to explain the material world and the
natural phenomena of the universe. The scope of physics is very wide and vast. It
deals with not only the tinniest particles of atoms, but it also dwells upon natural
phenomenon like galaxy, milky way, solar and lunar eclipse etc.
 Branchesof Physics
Classical Physics
A branch of physics, which is mainly concerned with the laws of motion and
gravitation of Sir Isaac Newton and James Clark Maxwell’s Kinetic theory and
thermodynamics, is called classical physics. Classical physics is mainly concerned
with matter and energy. In classical physics energy and matter are considered as
separate entities. Acoustics, Optics, Classical mechanics and electromagnetics are
the traditional branches of classical physics. Moreover, any theory of physics, which
is considered null and void in the modern physics, automatically falls under the
realm of classical physics.

2. Modern Physics
Modern physics is the branch of physics, which is mainly concerned with the theory
of relativity and quantum mechanics. Albert Einstein and Max Plank were the
pioneers of modern of physics. They were the first scientists who laid down the
foundations of modern physics by introducing the theory of relativity and quantum
mechanics respectively. In modern physics energy and matter are not considered as
separate entities; rather they are considered as different forms of each other.
Nuclear Physics
Nuclear physics is the branch of physics which deals with constituents, structure,
behaviour and interactions of atomic nuclei. Encarta dictionary defines the nuclear
physics as “the branch of physics in which the structure, forces, and behavior of the
atomic nucleus are studied.” In the modern age, nuclear physics has got a very wide
scope. It is used in power generation, nuclear weapons, medicines etc.
Atomic Physics
Atomic physics is the branch of physics which deals with the composition of
atom apart from nucleus. It is mainly concerned with the arrangement and
behaviour of electrons in the shells around the nucleus.
Geophysics
Geophysics is the branch of physics which deals with the study of earth. It is
mainly concerned with the shape, structure and composition of earth. It also
studies the gravitational force, magnetic fields, earthquakes, magmas, eruption of
volcanoes etc.
Biophysics
Encarta Encyclopedia defines biophysics as “Biophysics, interdisciplinary study of
biological phenomena and problems, using the principles and techniques of
physics.” Biophysics studies only the biological problems and structure of
molecules in living organism in light of the techniques derived from physics. One of
the best achievements of biophysics is the structure of DNA (Deoxyribonucleic Acid).

3. Mechanics
Mechanics is the branch of physics which deals with the motion of material objects
under the influence of forces. Mechanics has been divided into two main branches:
Classical mechanics and Quantum mechanics. Classical mechanics deals with the
laws of motion of physical objects and the forces that cause the motion, while
quantum mechanics is the branch of physics which deals with the behaviour of
smallest particles i.e., electrons, neutrons and protons. According to Encarta
dictionary, “Quantum mechanics is the study evolved in an effort to explain the
behavior of atoms and subatomic particles, which do not obey the laws of classical
Newtonian mechanics.”
Acoustics
The word acoustics has been derived from a Greek word akouen, meaning to hear.
Hence, we can define acoustics as a branch of physics, which studies how sound is
produced, transmitted, received and controlled, is called acoustics. It also deals with
the effects of sounds in various mediums i.e., gases, liquids and solids.
Optics
Optics is the branch of physics, which deals with the propagation, behaviour and
properties of light. Encarta Encyclopedia defines Optics as “a branch of physical
science dealing with the propagation and behavior of light. In a general sense, light is
that part of the electromagnetic spectrum that extends from X rays to microwaves
and includes the radiant energy that produces the sensation of vision.”
Thermodynamics
Thermodynamics is the branch of physics, which deals with the study of heat and its
relation with energy and work. According to National Aeronautics and Space
Administration, USA, “Thermodynamics is the study of effects of work, heat and
energy on a system. Thermodynamics is only concerned with large scale
observations.”
Astrophysics
The word astrophysics is a combination of two words astro which means star,
while the word phisis means nature. Thus, astrophysics can be defined as a
branch of astronomy which is concerned with the study of universe i.e., stars,
galaxies and planets using the laws of physics.

4. Blaise Pascal was a French
mathematician and physicist who laid the foundation for
the modern theory of probabilities. A multi-faceted
personality, he was also a Christian philosopher, inventor,
and writer. Born as the son of a talented mathematician, he
received his primary education from his father, who
through his unorthodox curriculum, wanted to ensure that
his bright young son grew up in an intellectually
stimulating environment. The boy started displaying signs
of brilliance at an early age and was regarded as a child
prodigy. He was just 16 when he wrote a significant
treatise on the subject of projective geometry and started
working on other serious mathematical concepts as well.
While still in his teens he began building calculating
machines which later became known as Pascal’s
calculators. The calculators, which he had developed with
the aim of helping his father in calculating taxes, became
Pascal’s first claim to fame. Over the next several years he
researched and wrote extensively on mathematical
theories and also experimented in physical sciences.
Throughout his life he made numerous great contributions
to the philosophy of mathematics and the physical
sciences. As a Christian philosopher, his most influential
theological work is considered to be the ‘Pensées’ which
unfortunately he could not complete before illness claimed
him at the relatively young age of 39.
Blaise Pascal
Marie Curie
She was responsible for coining the term
radioactivity and theorizing the concept, in addition
to discovering two elements polonium and radium
and finding techniques for isolating radioactive
isotopes.

5. Law of Inertia
The law of inertia states that an object at rest stays at rest and an object in
motion stays in motion with the same speed and in the same direction unless
acted upon by an unbalanced force. The law of inertia is sometimes referred to as
Newton's first law of motion.
Sir Isaac Newton presented his three laws of motion for the first time in 1686 in
"Principia Mathematica Philosophiae Naturalis." The first law, the law of inertia,
states that an object's velocity will change only if there is an external force
making it change.
A good example of this law as seen in everyday life is that of a kite flying in the
sky. The kite will remain in the air, at its current velocity unless it is changed by
the speed or direction of the wind. Another excellent example of Newton's first
law is seen when a package is dropped out of a moving airplane. The package will
continue falling at the speed at which the airplane was moving until an external
force, in this case, gravity, makes velocity change.
If an object has no velocity, that object remains at rest. Nothing will change that
unless an external force moves it. The amount of change that object is subjected
to is explained by Newton's second law of motion which states that a force is
equal to the change in momentum.
Law of Acceleration
Newton's first law of motion predicts the behavior of objects for which all existing forces
are balanced. The first law - sometimes referred to as the law of inertia - states that if
the forces acting upon an object are balanced, then the acceleration of that object will
be 0 m/s/s. Objects at equilibrium (the condition in which all forces balance) will not
accelerate. According to Newton, an object will only accelerate if there is
a net or unbalanced force acting upon it. The presence of an unbalanced force will
accelerate an object - changing its speed, its direction, or both its speed and direction.
Newton's second law of motion pertains to the behavior of objects for which all existing
forces are not balanced. The second law states that the acceleration of an object is
dependent upon two variables - the net force acting upon the object and the mass of the
object. The acceleration of an object depends directly upon the net force acting upon
the object, and inversely upon the mass of the object. As the force acting upon an
object is increased, the acceleration of the object is increased. As the mass of an object
is increased, the acceleration of the object is decreased.

6. Law of Interaction
Sir Isaac Newton's third law states that for every action (force) in nature, there is an
equal and opposite reaction. In other words, if object A exerts a force on object B, then
object B also exerts an equal and opposite force on object A. Notice that the forces are
exerted on different objects.. For aircraft, the principal of action and reaction is very
important. It helps to explain the generation of lift from an airfoil. In this problem, the air
is deflected downward by the action of the airfoil, and in reaction the wing is pushed
upward. Similarly, for a spinning ball, the air is deflected to one side, and the ball reacts
by moving in the opposite direction. A jet engine also produces thrust through action
and reaction. The engine produces hot exhaust gases which flow out the back of the
engine. In reaction, a thrusting force is produced in the opposite direction.
A force is a push or a pull upon an object that results from its interaction with another
object.
Technology that is a product of Physics
LIQUID CRYSTAL DISPLAY MATERIALS
Liquid crystals are materials in which the molecules
show a preference for alignment with their neighboring
molecules even though they can be in a liquid state
having no long-range translational order. The molecules
in these liquid crystalline phases are easy to orient by
the application of an electric field and so can be made
to act as a switch for light if they are placed between
crossed polarizers and electrodes. Fundamental
research on the physics and phase transitions of liquid
crystals began in the 1920s, but it was not until the early
1970s that the first liquid crystal displays were
developed. Flat-panel liquid crystal displays have only
been manufactured in great volume in the last decade.
Active-matrix liquid crystal displays used for the highest
performance laptops today have high resolution and
brightness as well as full color at high speed due to the
separate electrical switching elements for each of about
1 million separate picture elements or pixels in the
display. Extensive research being carried out today will
eventually allow high-performance flexible displays on
plastic substrates, with higher resolution and at lower
manufacturing cost, which will in turn drive new
technology, markets, and applications.