Physics
(notes)
For
Class 9
th
Written by Shahid Ahmad Bangash E-mail address: Mr_shahid_ahmad@yahoo.com
Mobil No: 0314-9132833
Chapter 1
Introduction
Physics: the branch of science concerned with the properties (‍ ) ت‏of matter and energy and the relationships between them
Branches of physics 1) Mechanic: The branch of physics that is concerned (#$%&) with the
analysis (‍ )&*)(Ű â€Źof the action of forces on matter or material systems. 2) Heat: A form of energy associated (â€ŤŰ â€Ź-$%./) with the motion of atoms or
molecules and capable of being transmitted (1-.2/) through solid and fluid media by conduction, through fluid media by convection, and through empty space by radiation. 3) Light: light is a form of energy. Its different properties like reflection,
refraction, dispersion etc. some optical instruments like microscope, telescope, camera and mirrors are also studied 4) Nuclear physics: the branch of physics concerned with the structure
and behavior (‍ )ŘąŮˆ(Ű â€Źof the nucleus and the particles of which it consists 5) Atomic physics: The branch of physics that is concerned with the
structure of the atom, the characteristics (‍ ) ت‏of the elementary particles of which the atom is composed (19.:/).
6) Biophysics: The branch of physics that is concerned with the
application of physics to biological processes (19;) and phenomena 7) Astrophysics: the branch of physics concerned with the physical
nature of heavenly (<= 9>?) bodies. 8) Electricity and magnetism: it deals with the study of electrical charge
and relationship between Electricity and magnetism.
1
Chapter 1 9) Solid state physics - the branch of physics that studies the properties
of materials in the solid state. 10) Plasma physics: it deal with study of fourth state of matter is called
plasma. Plasma is a state of matter similar to gas in which a certain
portion of the particles are ionized.
11) Elementary particle physics: The branch of physics that deals with
subatomic particles i.e. electron, proton, neutron. 12) Geophysics: the study of the earth's physical properties and of the
physical processes acting upon, above, and within (رC= )اthe earth.
13) Health physics: it deals with the study of the effect of radioactive rays
on living bodies and methods of protection against.
Importance of physics Physics has great importance in our daily life and some of them are given below. 1)
Satellite: we can watch any event from any part of the world due to satellite communication.
2) Computer: we can calculate large data in few second and
increase the
speed of work with help of computer. 3) Microscope: it is gift of physics by which we can study small things that
we cannot see by nick eye. 4) Telescope: it is now easy to study heavenly bodies with the help of telescope 5) Atomic bomb: we have been able to make strong defense by atomic
bomb. 6) Electricity: electricity has made possible all the comports of life.
2
Chapter 1
7) Engines: the inventions of different heat engines have enabled man to
run vehicles and fly airplanes. 8) Freezers: we can preserve ( FG) food in deep freezers. 9)
Physics plays an important role in health, economic (I د.K)ا development, education, energy, and the environment. Our modern world is much more connected than in previous historical times. These days we travel far and fast, communicate easily and quickly.
Scientific method Science is the organized body of knowledge there is specific method of acquiring, organizing and promoting (وغMN) this knowledge. This method is called scientific method. Following are the basic component of scientific method.
1)
Observation: this is a first step of scientific method. Observation means to examine carefully.
The ability of a measurement to match the actual value of the quantity being measured and recorded it carefully.
2) Accurate measurement:
3) Analysis: analysis starts from the recorded data. In this step we
look for a relationship among various physical quantities. 4) Hypothesis: hypothesis is based on analysis in which a few number
of assumption are made to explain the observed phenomenon.
5) Experiment: when number of hypothesis is made than it confirmed
(#(C &) by experiment.
3
Chapter 1
6) Theory: if the hypothesis found to be true with the help of
experiment. It became a theory.
7) Law: when the theory is verified by a series of experiments, it
becomes a law. Law is a comprehensive (O/ P) statement which explains the observations and experiments.
Give a brief sketch ( ) ہof the scientific achievements ( ) ںof the Muslim scientist. Yaqub kindi: He is born in 800 A.D in basra (Iraq) and after spending a useful life died in 873 A.D Contributions 1) 2) 3) 4) 5) 6) 7)
He produced extensive (O > )وresearch on meteorology and specific gravity. He worked a lot on optics specially on reflection of light He discussed music from scientific point of view and expresses (M ﮨS) the notes of music in terms of frequencies. He wrote 241 books out of which 12 were on physics. He did valuable (<.9 K) work on geometrical optics. Most of his books especially on optics are translated in Latin. He also worked a lot in the field of medicine.
Ibn-ul- haitham: ibn-ul-haitham was born in 965 A.D. after completing education he served (T/C ) in Govt office for some time. Then he went to Egypt and got admission in the great institution bait-ul-hikmat and spent his whole life in research work and writing books. He died in 1039 A.D. Contributions 1)
4
He was the first to say that light is a form of energy.
Chapter 1
2) He did research work on reflection and refraction of light and 3) 4) 5) 6) 7)
discovered laws of reflection. His most famous book kitab-ul-manazir is written on optics. He invented pinhole camera and got the image of sun eclipse. ( UﮨMV ) > رج He divided the things into luminous and non-luminous. He discussed and explained human eye in detail. He constructed the spherical mirror.
Al-Beruni: the most famous scientist of golden age of Islam, al Beruni was born in 973 A.D in a small town Berun in Afghanistan. Contributions 1) 2) 3) 4) 5) 6) 7)
He wrote 150 books on different subjects of science like chemistry, biology, geology and geography. In his famous book Qanoon-ul-massodi he discussed the shape and measurements of earth. He found the methods of calculating latitude (C$G لY) and longitude (C$G ضM;) of a place. He discussed the movement of moon, its different phases and other planets. He determined the circumference of earth. He determined the densities of different substance. He said that Indus valley was once the basin of an ocean which was gradually filled with mud.
Dr. Abdussalam: He was born at Jhang in Pakistan in 1926. He did his M.sc in physics from Govt College. He did his PhD from Cambridge. He came to Pakistan but soon went back to U.K for research work. He died in 1996 in England. Contributions 1)
5
He presented Grand unification theory and was awarded Nobel Prize for this theory in 1979.
Chapter 1
2) He devoted his life for the progress of science and technology 3) 4) 5) 6)
in developing countries. He was the director of international center for technological physics at Trieste (Italy) He was appointed as professor of physics at imperial college London. He was awarded Nishan-e- Pakistan by the Govt of Pakistan. He was of the view that atomic energy should be used for peaceful purposes
Dr. Abdul Qadir Khan: He was born in 1936 at Bhopal in India. He migrated to Pakistan in 1952, and got BSc degree from Karachi, than he went to Europe and got M.sc technology degree from Holland. He got Ph.D. degree from the University of Leaven. He come to Pakistan in 1975 and devoted his life for the nuclear program of Pakistan. Contributions 1) 2) 3) 4) 5)
He is the first known Muslim scientist. He established kahuta research laboratories. The engineering research laboratories Islamabad is renamed as A.Q khan laboratories. He has been awarded Tamgha-e-imtiaz by the Govt of Pakistan. Because of his efforts Pakistan was able to conduct atomic explosion on 28th may 1998.
Written by Shahid Ahmad Bangash E-mail address: Mr_shahid_ahmad@yahoo.com
Mobil No: 0314-9132833
6
Chapter 1
7