Physical Word

Physical Word Science (“To know” ) is a systematic attempt to (i) Unification :understand natural phenomena in as much detail and Unification means attempting to explain diverse depth as possible and use the knowledge so gained physical phenomena in terms of few concepts and to predict, modify and control phenomena”. laws. The scientific method involves several interconnected (ii) Reductionism :steps : Reductionism means attempting to explain derive the properties of a bigger, more complex system from 1. Systematic Observations the properties of its constituent simpler parts. 2. Controlled Experiments 3. Quantitative & Qualitantive Reasoning SCOPE AND EXCITMENT OF PHYSICS 4. Mathematical modelling 5. Prediction Scope of physics can be explained in its 2 sub disciplines :- 6. Verification of Theories 1. Macroscopic Domain 2. Microscopic Domain PHYSICS Physics is a branch of science which comes from greek word “fusis” meaning nature. “Physics can be described as a study of a basic laws of nature & their manifestation in different natural phenomena.” 1. Macroscopic Domain :- Macroscopic Domain includes phenomena at labouratory, terestrial and astronomical scales. 2. Microscopic Domain :- Microscopic Domain includes atomic, molecules and nuclear phenomena 2Basic Principles of Physics :(i) Unification (ii) Reduction Classic physics deals mainly with macroscopic phenomena eg - Mechanics, Electro dynamics, optics and thermodynamics. Physical Word Microscopic domain of physics deal with the constitution and structure of matter at the minute scales of atoms and nuclei and their interaction with other particles. PHYSICS, TECHNOLOGY & SOCIETY The domain intermediate between the macroscopic and the microscopic domain is called mesoscopic domain. Physics is the study of nature and natural phenomena, physicists try to discover the rules that are operating in nature on the basis of observation, experimentation and analysis some of these rules concerning their discover names are :- S.No. Name Discovery Country 1. Archimedes Principle of buoyancy Greece 2. Galileo galille Law of Inertia Italy 3. Christian Huygens Wave theory of light Holland 4. 5. 6. Laws of electromagnetic Induction Electromagnetic Theory, lightJames Clerk Maxwell an Electromagnetic wave Jagdish Chandra Ultra Short radio waves Bose Michael Faraday U.K. U.K. India LINK BETWEEN TECHNOLOGY AND PHYSICS S. NO. TECHNOLOGY SCIENTIFIC PRINCIPLES 1. Steam Engine Laws of Thermodynamics 2. Radio & Television Generation, Propagation & detection of Electromagnetic waves 3. Computer Digital logic 4. Lasers Light amplification by stimulated emission of radiation. 5. Rocket Populism Newton’s laws of motion 6. Electric Generator Faraday law of electromagnetic induction 7. Aeroplane Bernoulli’s principle in fluid dynamics FUNDAMENTAL FORCE IN NATURE Physical Word For moving condition :- Both electric and magnetic fields are produced which gives rise to a force on 1. 4 fundametal natural forces are found in nature :- moving charge. Gravitational forces :- It is a Universal force. It is a mutual attraction force between any two objects by virtue of their masses. it plays a key role in the large scale phenomena of the universe, such as formation and evolution of stars, galaxies and galactic clusters. It was explained by Newton thats why it is called. Newtons laws of gravitation. Electric & magnetic effects are generally inseperable F= GM1 M 2 r2 thats why it is called Electromagnetic force. It acts over large distance and does not need any intervening medium. It is a stronger force than gravitational force. It may be attractive or repulsive force. F= K q1 q 2 r2 There F = Gravitation Force G = Gravitational constant = 6.67  10-11 Nm2/kg2 M1= Mass of Earth M2= Mass of object/planet r = Distance between Earth & Object/planet. F = Electromagnetic force q1 = Charge1 q2 = Charge2 r = Distance between both charges. 9 K = 9  10 This force is weakest force in nature. It is always an attractive force. Nm 2 c2 Strong Nuclear Force :Force which binds protons and neutrons in a nucleas. It is charge independent and acts equally between a proton and a proton, neutron and a neutron and a proton and a neutron. These force have the shortest range. The gravitional forse causes the apple to fall as well Weak Nuclear forces :as planets to resolve around the sun The weak nuclear forces are the forces of interaction 2. Electromagnetic Force :- It is force between charged particles between unlike charges attraction force works and between like charges repulsion force works. For rest condition :- Charges produce only electric field. between elementary particles of short life times. These forces were discovered during the study of the phenomenon of  -decay in radioactivity.. FG : FW : FE : FS = 1 : 1025 : 1036 : 1038