Physics class 11 topic no.1

1. PHYSICAL
WORLD
• By…….Vidya gaude

2. Rainbow (Dispersion of light) Lightning (electrical discharge) Gravitational force
Planatery motion (Kepler’s law)
Study Basic laws
of nature
Presented it
in terms of
theories

3. WHAT IS PHYSICS ?
Physics is a study of basic laws of nature and their
manifestation in different phenomena's.
Manifestation: the action or fact of showing something
(Display, demonstration, exhibition, presentation,
illustration, etc)
 The word Physics comes from a Greek word (ἡ φύσις) meaning nature.
 Its Sanskrit equivalent is Bhautiki ( to the study of the Physical world)

4. SCIENTIFIC METHOD
It includes steps :
• Observations
• Controlled experiments,
• Qualitative and quantitative reasoning,
• Mathematical modeling,
• Prediction
• Verification or falsification of theories.
Law of
gravitation
𝑭 =
𝑮𝒎 𝟏 𝒎 𝟐
𝑹 𝟐

5. There are two domains :
 Macroscopic: includes phenomena at the laboratory, terrestrial and
astronomical scales.
 Microscopic: includes atomic, molecular and nuclear phenomena

6. Physics
Classical
Physics
Mechanics Optics
Electromag
netism
Thermodyn
amics
Modern
physics
Atomic
Physics
Quantum
Physics
Nuclear
Physics
Branches of physics

7. EXCITEMENT OF PHYSICS
What we know is a drop,
what we don't know is an ocean.”
― Isaac Newton
EX:
 The states of matter
* Solids, Liquids, Gases,
* Plasma,
* Bose-Einstein Condensate
 Why does the sky sometimes
appear purple?

8. PHYSICS, TECHNOLOGY AND SOCIETY PHYSICS TECHNOLOGY
Silicon Chip Technology-
(Integrated circuit IC)
Triggered the computer revolution.
The Wireless Communication Technology-
(laws of electricity and magnetism)
Cellphones, Tablets, computers & internet, TV, Radio
Nuclear Technology-
(Phenomenon of neutron-induced fission of uranium.)
Nuclear power reactors and nuclear weapons
Tarapur nuclear powerKudankulam Nuclear Power Plant
Agni-V missile
( Defence Research and
Development Organisation DRDO)

9. SOME PHYSICISTS AND THEIR MAJOR CONTRIBUTIONS-
1. Isaac Newton ( U.K)
 Universal law of gravitation,
 Laws of motion,
 Reflecting telescope
2. Albert Einstein (Germany)
 Explanation of photoelectric effect,
 Theory of relativity
E = mc2.
“Anyone who has never made a mistake
has never tried anything new.”

10. J.J Thompson
the discovery of the
electron
Niels Bohr
the Bohr model
of the atom
Charles-Augustin de Coulomb
the Columb’s law, which explains the
electrostatic attraction and repulsion.
Georg Simon Ohm
the “Ohm’s Law”
John Clerk Maxwell
Electromagnetism
Nikola Tesla
Alternating current (AC) system
Michael Faraday
Electromagnetic induction and came up with
the idea for first electrical transformer

11. Explaining Black holes and Advances on the General
Theory of Relativity and Quantum mechanics
Stephen Hawking
He has also published several books including
 A brief History of Time,
 Black Holes and Baby Universes
 The Universe in a Nutshell
“Although I cannot move
and I have to speak
through a computer, in
my mind I am free.”

12. Sir. C.V. Raman (India)
Inelastic scattering of light by molecules
The Nobel Prize in Physics 1930 for his
work on the scattering of light.
The discovery of the effect named after him.
“Raman effect” (“Raman scattering”)
(discovered on 28 February 1928 )
The day is celebrated by the Government of
India as the National Science Day every year.

13. Satyendra Nath Bose
Theory of the
Bose–Einstein condensate
Vikram Sarabhai
Father of the
Indian Space Program
Homi J. Bhabha
known as
"father of the Indian nuclear programme"
Bhabha was also the founding director of the Atomic
Energy Establishment, Trombay (AEET) which is now
named the Bhabha Atomic Research Centre in his honour

14. FUNDAMENTAL FORCES IN NATURE
1. Strong nuclear force
2. Electromagnetic force
3. Weak nuclear force
4. Gravitational force
Strongest
Weakest

15. CREDITS
• wikipedia.org
• wikipedia.org/wiki/Physicist ( slide no. 9 to 13)
• https://themuslimtimesdotinfodotcom.files.wordpress.com/2019/08/apple-hitting-
newtons-head-animation.gif?w=650&zoom=2 ( slide no. 4 )
• https://www.google.co.in/url?sa=i&url=https%3A%2F%2Fwww.freepik.com%2Ffree-
vector%2Fboy-throwing-ball-
white_6829919.htm&psig=AOvVaw2XZ2dsI6uxfwOwncAGsT4R&ust=15994975641760
00&source=images&cd=vfe&ved=0CAIQjRxqFwoTCPitmPX-
1OsCFQAAAAAdAAAAABAD
( slide no. 4 )