Indian Railways, Railway Reservation, pnr status.

Indian railways, the world’s fourth largest rail network, was founded in 1857, much before Indian Independence. Lets dig out more about Indian Railways, railway reservation and how to book train tickets online.

Indian Railways (IR) is operated by government of India. Every day, millions of people travel via trains and loads of trains run daily including rajdhani, super fast express, cargo, local and metro trains. The entire network has given jobs to millions of people. There are more than 7000 stations in India. Indian Railways have been divided into several zones and subzones including Southern railway, central railway, etc.

Types of Railway Reservation

• 1A – The first class Ac train reservation is the most costly of all types ofrailway reservation. Also such tickets are provided only on popular and metropolitan routes. Such coaches have full cabin like features, sleeping facilities and privacy like personal coupes.
• 2A -AC – Two tier – Less expensive than 1A. Provided with sleeping berths, curtains, bedding and fooding.
• FC – First class – This is same as 1 A without ac facility.
• 3A – AC – Three tier – Less expensive than 2A. Air conditioned coaches. Sleeping berths.
• 3E – AC three tier Economy – Air conditioned coaches with sleeping facility but cheaper than 3A present in Garib Rath trains (Fully Air conditioned train with affordable fair for common man.)
• CC - ac chair car – for traveling between cities as it come with seating facility only.
• SL – The most common railway reservation type. People sit in these coaches during daytime while they sleep during nights. It is inexpensive, affordable and most widely preferred by Indian population.
• 2S – Same as AC car but without air conditioning.
• UR - Unreserved – Entry into these coaches are guaranteed if you have a ticket but seat is not. This type of ticket is the cheapest one and always available to buy or book.

Depending upon the train and reservation types and distance, the fare varies.

How to check PNR status ?

• TO check pnr status, just go to http://indianrail.gov.in/pnr_Enq.html
• Enter your pnr number in the given box
• Hit on Get status. This will show your current status be it confirm, rac, chart not prepared, etc.

How to make railway reservation online :

Official website for making railway reservation online is http://irctc.co.in

• Just go and register on this website.
• Plan your travel. Chose from and to destination.
• Chose reservation type.
• continue to payment page where you can pay via credit cards, debit cards, cash cards, atm cards, netbanking, etc.
• Print the eticket
• Note: on your journey, don’t forget to bring a photo id proof or a driving license for verification purpose.

Happy Journey.
.

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Some of the common computing or computer technology

Some of the common computing or computer technology related abbreviations and their full-forms :

ADSL – Asymmetric Digital Subscriber Line
AGP – Accelerated Graphics Port
ALI – Acer Labs, Incorporated
ALU – Arithmetic Logic Unit
AMD – Advanced Micro Devices
APC – American Power Conversion
ASCII – American Standard Code for Information Interchange
ASIC – Application Specific Integrated Circuit
ASPI – Advanced SCSI Programming Interface
AT – Advanced Technology
ATI – ATI Technologies Inc.
ATX – Advanced Technology Extended

— B —
BFG – BFG Technologies
BIOS – Basic Input Output System
BNC – Barrel Nut Connector

— C —
CAS – Column Address Signal
CD – Compact Disk
CDR – Compact Disk Recorder
CDRW – Compact Disk Re-Writer
CD-ROM – Compact Disk – Read Only Memory
CFM – Cubic Feet per Minute (ft�/min)
CMOS – Complementary Metal Oxide Semiconductor
CPU – Central Processing Unit
CTX – CTX Technology Corporation (Commited to Excellence)

— D —

DDR – Double Data Rate
DDR-SDRAM – Double Data Rate – Synchronous Dynamic Random Access Memory
DFI – DFI Inc. (Design for Innovation)
DIMM – Dual Inline Memory Module
DRAM – Dynamic Random Access Memory
DPI – Dots Per Inch
DSL – See ASDL
DVD – Digital Versatile Disc
DVD-RAM – Digital Versatile Disk – Random Access Memory

— E —
ECC – Error Correction Code
ECS – Elitegroup Computer Systems
EDO – Extended Data Out
EEPROM – Electrically Erasable Programmable Read-Only Memory
EPROM – Erasable Programmable Read-Only Memory
EVGA – EVGA Corporation

— F —
FC-PGA – Flip Chip Pin Grid Array
FDC – Floppy Disk Controller
FDD – Floppy Disk Drive
FPS – Frame Per Second
FPU – Floating Point Unit
FSAA – Full Screen Anti-Aliasing
FS – For Sale
FSB – Front Side Bus

— G —
GB – Gigabytes
GBps – Gigabytes per second or Gigabits per second
GDI – Graphical Device Interface
GHz – GigaHertz

— H —
HDD – Hard Disk Drive
HIS – Hightech Information System Limited
HP – Hewlett-Packard Development Company
HSF – Heatsink-Fan

— I —
IBM – International Business Machines Corporation
IC – Integrated Circuit
IDE – Integrated Drive Electronics
IFS- Item for Sale
IRQ – Interrupt Request
ISA – Industry Standard Architecture
ISO – International Standards Organization

— J —
JBL – JBL (Jame B. Lansing) Speakers
JVC – JVC Company of America

- K —
Kbps – Kilobits Per Second
KBps – KiloBytes per second

— L —
LG – LG Electronics
LAN – Local Area Network
LCD – Liquid Crystal Display
LDT – Lightning Data Transport
LED – Light Emitting Diode

— M —
MAC – Media Access Control
MB � MotherBoard or Megabyte
MBps – Megabytes Per Second
Mbps – Megabits Per Second or Megabits Per Second
MHz – MegaHertz
MIPS – Million Instructions Per Second
MMX – Multi-Media Extensions
MSI – Micro Star International

— N —
NAS – Network Attached Storage
NAT – Network Address Translation
NEC – NEC Corporation
NIC – Network Interface Card

— O —
OC – Overclock (Over Clock)
OCZ – OCZ Technology
OEM – Original Equipment Manufacturer

— P —
PC – Personal Computer
PCB – Printed Circuit Board
PCI – Peripheral Component Interconnect
PDA – Personal Digital Assistant
PCMCIA – Peripheral Component Microchannel Interconnect Architecture
PGA – Professional Graphics Array
PLD – Programmable Logic Device
PM – Private Message / Private Messaging
PnP – Plug ‘n Play
PNY – PNY Technology
POST – Power On Self Test
PPPoA – Point-to-Point Protocol over ATM
PPPoE – Point-to-Point Protocol over Ethernet
PQI – PQI Corporation
PSU – Power Supply Unit

— R —
RAID – Redundant Array of Inexpensive Disks
RAM – Random Access Memory
RAMDAC – Random Access Memory Digital Analog Convertor
RDRAM – Rambus Dynamic Random Access Memory
ROM – Read Only Memory
RPM – Revolutions Per Minute

— S —
SASID – Self-scanned Amorphous Silicon Integrated Display
SCA – SCSI Configured Automatically
SCSI – Small Computer System Interface
SDRAM – Synchronous Dynamic Random Access Memory
SECC – Single Edge Contact Connector
SODIMM – Small Outline Dual Inline Memory Module
SPARC – Scalable Processor ArChitecture
SOHO – Small Office Home Office
SRAM – Static Random Access Memory
SSE – Streaming SIMD Extensions
SVGA – Super Video Graphics Array
S/PDIF – Sony/Philips Digital Interface

— T —
TB – Terabytes
TBps – Terabytes per second
Tbps – Terabits per second
TDK – TDK Electronics
TEC – Thermoelectric Cooler
TPC – TipidPC
TWAIN – Technology Without An Important Name

— U —
UART – Universal Asynchronous Receiver/Transmitter
USB – Universal Serial Bus
UTP – Unshieled Twisted Pair

— V —
VCD – Video CD
VPN – Virtual Private Network

— W —
WAN – Wide Area Network
WTB – Want to Buy
WYSIWYG – What You See Is What You Get

— X —
XGA – Extended Graphics Array
XFX – XFX Graphics, a Division of Pine
XMS – Extended Memory Specification
XT – Extended Technology

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IIT-JEE Syllabus

Physics Syllabus: General: Units and dimensions, dimensional analysis; least count, significant figures; Methods of measurement and error analysis for physical quantities pertaining to the following experiments: Experiments based on using Vernier calipers and screw gauge (micrometer), Determination of g using simple pendulum, Young’s modulus by Searle’s method, Specific heat of a liquid using calorimeter, focal length of a concave mirror and a convex lens using u-v method, Speed of sound using resonance column, Verification of Ohm’s law using voltmeter and ammeter, and specific resistance of the material of a wire using meter bridge and post office box. Mechanics: Kinematics in one and two dimensions (Cartesian coordinates only), projectiles; Uniform Circular motion; Relative velocity. Newton’s laws of motion; Inertial and uniformly accelerated frames of reference; Static and dynamic friction; Kinetic and potential energy; Work and power; Conservation of linear momentum and mechanical energy. Systems of particles; Centre of mass and its motion; Impulse; Elastic and inelastic collisions.  Law of gravitation; Gravitational potential and field; Acceleration due to gravity; Motion of planets and satellites in circular orbits; Escape velocity. Rigid body, moment of inertia, parallel and perpendicular axes theorems, moment of inertia of uniform bodies with simple geometrical shapes; Angular momentum; Torque; Conservation of angular momentum; Dynamics of rigid bodies with fixed axis of rotation; Rolling without slipping of rings, cylinders and spheres; Equilibrium of rigid bodies; Collision of point masses with rigid bodies. Linear and angular simple harmonic motions. Hooke’s law, Young’s modulus. Pressure in a fluid; Pascal’s law; Buoyancy; Surface energy and surface tension, capillary rise; Viscosity (Poiseuille’s equation excluded), Stoke’s law; Terminal velocity, Streamline flow, equation of continuity, Bernoulli’s theorem and its applications. Wave motion (plane waves only), longitudinal and transverse waves, superposition of waves; Progressive and stationary waves; Vibration of strings and air columns;Resonance; Beats; Speed of sound in gases; Doppler effect (in sound). Thermal physics: Thermal expansion of solids, liquids and gases; Calorimetry, latent heat; Heat conduction in one dimension; Elementary concepts of convection and radiation; Newton’s law of cooling; Ideal gas laws; Specific heats (Cv and Cp for monoatomic and diatomic gases); Isothermal and adiabatic processes, bulk modulus of gases; Equivalence of heat and work; First law of thermodynamics and its applications (only for ideal gases);  Blackbody radiation: absorptive and emissive powers; Kirchhoff’s law; Wien’s displacement law, Stefan’s law. Electricity and magnetism: Coulomb’s law; Electric field and potential; Electrical potential energy of a system of point charges and of electrical dipoles in a uniform electrostatic field; Electric field lines; Flux of electric field; Gauss’s law and its application in simple cases, such as, to find field due to infinitely long straight wire, uniformly charged infinite plane sheet and uniformly charged thin spherical shell. Capacitance; Parallel plate capacitor with and without dielectrics; Capacitors in series and parallel; Energy stored in a capacitor. Electric current; Ohm’s law; Series and parallel arrangements of resistances and cells; Kirchhoff’s laws and simple applications; Heating effect of current. Biot–Savart’s law and Ampere’s law; Magnetic field near a current-carrying straight wire, along the axis of a circular coil and inside a long straight solenoid; Force on a moving charge and on a current-carrying wire in a uniform magnetic field. Magnetic moment of a current loop; Effect of a uniform magnetic field on a current loop; Moving coil galvanometer, voltmeter, ammeter and their conversions. Electromagnetic induction: Faraday’s law, Lenz’s law; Self and mutual inductance; RC, LR and LC circuits with D.C. and A.C. sources. Optics: Rectilinear propagation of light; Reflection and refraction at plane and spherical surfaces; Total internal reflection; Deviation and dispersion of light by a prism; Thin lenses; Combinations of mirrors and thin lenses; Magnification.  Wave nature of light: Huygen’s principle, interference limited to Young’s double-slit experiment. Modern physics: Atomic nucleus; Alpha, beta and gamma radiations; Law of radioactive decay;  Decay constant; Half-life and mean life; Binding energy and its calculation; Fission and fusion processes; Energy calculation in these processes. Photoelectric effect; Bohr’s theory of hydrogen-like atoms; Characteristic and continuous X-rays, Moseley’s law; de Broglie wavelength of matter waves.

Chemistry Syllabus: Physical chemistry General topics: Concept of atoms and molecules; Dalton’s atomic theory; Mole concept; Chemical formulae; Balanced chemical equations; Calculations (based on mole concept) involving common oxidation-reduction, neutralisation, and displacement reactions; Concentration in terms of mole fraction, molarity, molality and normality. Gaseous and liquid states: Absolute scale of temperature, ideal gas equation; Deviation from ideality, van der Waals equation; Kinetic theory of gases, average, root mean square and most probable velocities and their relation with temperature; Law of partial pressures; Vapour pressure; Diffusion of gases. Atomic structure and chemical bonding:  Bohr model, spectrum of hydrogen atom, quantum numbers; Wave-particle duality, de Broglie hypothesis; Uncertainty principle; Qualitative quantum mechanical picture of hydrogen atom, shapes of s, p and d orbitals; Electronic configurations of elements (up to atomic number 36); Aufbau principle; Pauli’s exclusion principle and Hund’s rule; Orbital overlap and covalent bond; Hybridisation involving s, p and d orbitals only; Orbital energy diagrams for homonuclear diatomic species;  Hydrogen bond; Polarity in molecules, dipole moment (qualitative aspects only); VSEPR model and shapes of molecules (linear, angular, triangular, square planar, pyramidal, square pyramidal, trigonal bipyramidal, tetrahedral and octahedral). Energetics: First law of thermodynamics; Internal energy, work and heat, pressure-volume work; Enthalpy, Hess’s law; Heat of reaction, fusion and vapourization; Second law of thermodynamics; Entropy; Free energy; Criterion of spontaneity. Chemical equilibrium:  Law of mass action; Equilibrium constant, Le Chatelier’s principle (effect of concentration, temperature and pressure); Significance of ΔG and ΔG° in chemical equilibrium; Solubility product, common ion effect, pH and buffer solutions;  Acids and bases (Bronsted and Lewis concepts); Hydrolysis of salts. Electrochemistry: Electrochemical cells and cell reactions; Standard electrode potentials; Nernst equation and its relation to ΔG; Electrochemical series, emf of galvanic cells; Faraday’s laws of electrolysis; Electrolytic conductance, specific, equivalent and molar conductivity, Kohlrausch’s law; Concentration cells. Chemical kinetics:  Rates of chemical reactions; Order of reactions; Rate constant; First order reactions; Temperature dependence of rate constant (Arrhenius equation). Solid state: Classification of solids, crystalline state, seven crystal systems (cell parameters a, b, c, α, β, γ), close packed structure of solids (cubic), packing in fcc, bcc and hcp lattices; Nearest neighbours, ionic radii, simple ionic compounds, point defects. Solutions:  Raoult’s law; Molecular weight determination from lowering of vapour pressure, elevation of boiling point and depression of freezing point. Surface chemistry:  Elementary concepts of adsorption (excluding adsorption isotherms); Colloids: types, methods of preparation and general properties; Elementary ideas of emulsions, surfactants and micelles (only definitions and examples). Nuclear chemistry:  Radioactivity: isotopes and isobars; Properties of α, β and γ rays; Kinetics of radioactive decay (decay series excluded), carbon dating; Stability of nuclei with respect to proton-neutron ratio; Brief discussion on fission and fusion reactions. Inorganic Chemistry Isolation/preparation and properties of the following non-metals: Boron, silicon, nitrogen, phosphorus, oxygen, sulphur and halogens; Properties of allotropes of carbon (only diamond and graphite), phosphorus and sulphur. Preparation and properties of the following compounds: Oxides, peroxides, hydroxides, carbonates, bicarbonates, chlorides and sulphates of sodium, potassium, magnesium and calcium; Boron: diborane, boric acid and borax; Aluminium: alumina, aluminium chloride and alums; Carbon: oxides and oxyacid (carbonic acid); Silicon: silicones, silicates and silicon carbide;  Nitrogen: oxides, oxyacids and ammonia; Phosphorus: oxides, oxyacids (phosphorus acid, phosphoric acid) and phosphine; Oxygen: ozone and hydrogen peroxide; Sulphur: hydrogen sulphide, oxides, sulphurous acid, sulphuric acid and sodium thiosulphate; Halogens: hydrohalic acids, oxides and oxyacids of chlorine, bleaching powder; Xenon fluorides. Transition elements (3d series): Definition, general characteristics, oxidation states and their stabilities, colour (excluding the details of electronic transitions) and calculation of spin-only magnetic moment; Coordination compounds: nomenclature of mononuclear coordination compounds, cis-trans and ionisation isomerisms, hybridization and geometries of mononuclear coordination compounds (linear, tetrahedral, square planar and octahedral). Preparation and properties of the following compounds: Oxides and chlorides of tin and lead; Oxides, chlorides and sulphates of Fe2+, Cu2+ and Zn2+; Potassium permanganate, potassium dichromate, silver oxide, silver nitrate, silver thiosulphate. Ores and minerals: Commonly occurring ores and minerals of iron, copper, tin, lead, magnesium, aluminium, zinc and silver. Extractive metallurgy: Chemical principles and reactions only (industrial details excluded); Carbon reduction method (iron and tin); Self reduction method (copper and lead); Electrolytic reduction method (magnesium and aluminium); Cyanide process (silver and gold). Principles of qualitative analysis: Groups I to V (only Ag+, Hg2+, Cu2+, Pb2+, Bi3+, Fe3+, Cr3+,  Al3+, Ca2+, Ba2+, Zn2+, Mn2+ and Mg2+); Nitrate, halides (excluding fluoride), sulphate and sulphide. Organic Chemistry Concepts: Hybridisation of carbon; Sigma and pi-bonds; Shapes of simple organic molecules; Structural and geometrical isomerism;  Optical isomerism of compounds containing up to two asymmetric centres, (R,S and E,Z nomenclature excluded); IUPAC nomenclature of simple organic compounds (only hydrocarbons, mono-functional and bi-functional compounds); Conformations of ethane and butane (Newman projections); Resonance and hyperconjugation; Keto-enol tautomerism; Determination of empirical and molecular formulae of simple compounds (only combustion method); Hydrogen bonds: definition and their effects on physical properties of alcohols and carboxylic acids; Inductive and resonance effects on acidity and basicity of organic acids and bases; Polarity and inductive effects in alkyl halides; Reactive intermediates produced during homolytic and heterolytic bond cleavage;  Formation, structure and stability of carbocations, carbanions and free radicals. Preparation, properties and reactions of alkanes: Homologous series, physical properties of alkanes (melting points, boiling points and density); Combustion and halogenation of alkanes; Preparation of alkanes by Wurtz reaction and decarboxylation reactions. Preparation, properties and reactions of alkenes and alkynes: Physical properties of alkenes and alkynes (boiling points, density and dipole moments); Acidity of alkynes; Acid catalysed hydration of alkenes and alkynes (excluding the stereochemistry of addition and elimination); Reactions of alkenes with KMnO4 and ozone; Reduction of alkenes and alkynes; Preparation of alkenes and alkynes by elimination reactions; Electrophilic addition reactions of alkenes with X2, HX, HOX (X=halogen) and H2O;  Addition reactions of alkynes; Metal acetylides. Reactions of benzene: Structure and aromaticity; Electrophilic substitution reactions: halogenation, nitration, sulphonation, Friedel-Crafts alkylation and acylation; Effect of  o-, m- andp-directing groups in monosubstituted benzenes. Phenols: Acidity, electrophilic substitution reactions (halogenation, nitration and sulphonation); Reimer-Tieman reaction, Kolbe reaction. Characteristic reactions of the following (including those mentioned above):  Alkyl halides: rearrangement reactions of alkyl carbocation, Grignard reactions,  nucleophilic substitution reactions;  Alcohols: esterification, dehydration and oxidation, reaction with sodium, phosphorus halides, ZnCl2/concentrated HCl, conversion of alcohols into aldehydes and ketones; Ethers:Preparation by Williamson’s  Synthesis; Aldehydes and Ketones: oxidation, reduction, oxime and hydrazone formation; aldol condensation, Perkin reaction; Cannizzaro reaction; haloform reaction and nucleophilic addition reactions (Grignard addition);  Carboxylic acids: formation of esters, acid chlorides and amides, ester hydrolysis; Amines: basicity of substituted anilines and aliphatic amines, preparation from nitro compounds, reaction with nitrous acid, azo coupling reaction of diazonium salts of aromatic amines, Sandmeyer and related reactions of diazonium salts; carbylamine reaction; Haloarenes: nucleophilic aromatic substitution in haloarenes and substituted haloarenes (excluding Benzyne mechanism and Cine substitution). Carbohydrates: Classification; mono- and di-saccharides (glucose and sucrose); Oxidation, reduction, glycoside formation and hydrolysis of sucrose. Amino acids and peptides: General structure (only primary structure for peptides) and physical properties. Properties and uses of some important polymers: Natural rubber, cellulose, nylon, teflon and PVC. Practical organic chemistry: Detection of elements (N, S, halogens); Detection and identification of the following functional groups: hydroxyl (alcoholic and phenolic), carbonyl (aldehyde and ketone), carboxyl, amino and nitro; Chemical methods of separation of mono-functional organic compounds from binary mixtures.

Mathematics Syllabus: Algebra: Algebra of complex numbers, addition, multiplication, conjugation, polar representation, properties of modulus and principal argument, triangle inequality, cube roots of unity, geometric interpretations. Quadratic equations with real coefficients, relations between roots and coefficients, formation of quadratic equations with given roots, symmetric functions of roots. Arithmetic, geometric and harmonic progressions, arithmetic, geometric  and harmonic means, sums of finite arithmetic and geometric progressions, infinite geometric series, sums of squares and cubes of the first n natural numbers. Logarithms and their properties. Permutations and combinations, Binomial theorem for a positive integral index, properties of binomial coefficients. Matrices as a rectangular array of real numbers, equality of matrices, addition, multiplication by a scalar and product of matrices, transpose of a matrix, determinant of a square matrix of order up to three, inverse of a square matrix of order up to three, properties of these matrix operations, diagonal, symmetric and skew-symmetric matrices and  their properties, solutions of simultaneous linear equations in two or three variables. Addition and multiplication rules of probability, conditional probability, Bayes Theorem, independence of events, computation of probability of events using permutations and combinations. Trigonometry: Trigonometric functions, their periodicity and graphs, addition and subtraction formulae, formulae involving multiple and sub-multiple angles, general solution of trigonometric equations. Relations between sides and angles of a triangle, sine rule, cosine rule, half-angle formula and the area of a triangle, inverse trigonometric functions (principal value only). Analytical geometry: Two dimensions: Cartesian coordinates, distance between two points, section formulae, shift of origin. Equation of a straight line in various forms, angle between two lines, distance of a point from a line; Lines through the point of intersection of two given lines, equation of the bisector of the angle between two lines, concurrency of lines;  Centroid, orthocentre, incentre and circumcentre of a triangle. Equation of a circle in various forms, equations of tangent, normal and chord. Parametric equations of a circle, intersection of a circle with a straight line or a circle, equation of a circle through the points  of  intersection of two circles and those of a circle and a straight line. Equations of a parabola, ellipse and hyperbola in standard form, their foci, directrices and eccentricity, parametric equations, equations of tangent and normal. Locus Problems. Three dimensions: Direction cosines and direction ratios, equation of a straight line in space, equation of a plane, distance of a point from a plane. Differential calculus: Real valued functions of a real variable, into, onto and one-to-one functions, sum, difference, product and quotient of two functions, composite functions, absolute value, polynomial, rational, trigonometric, exponential and logarithmic functions. Limit and continuity of a function, limit and continuity of the sum, difference, product and quotient of two functions, L’Hospital rule of evaluation of limits of functions. Even and odd functions, inverse of a function, continuity of composite functions, intermediate value property of continuous functions. Derivative of a function, derivative of the sum, difference, product and quotient of two functions, chain rule, derivatives of polynomial, rational, trigonometric, inverse trigonometric, exponential and logarithmic functions. Derivatives of implicit functions, derivatives up to order two, geometrical interpretation of the derivative, tangents and normals, increasing and decreasing functions, maximum and minimum values of a function, Rolle’s Theorem and Lagrange’s Mean Value Theorem. Integral calculus: Integration as the inverse process of differentiation, indefinite integrals of standard functions, definite integrals and their properties, Fundamental Theorem of Integral Calculus. Integration by parts, integration by the methods of substitution and partial fractions, application of definite integrals to the determination of areas involving simple curves. Formation of ordinary differential equations, solution of homogeneous differential equations, separation of variables method, linear first order differential equations. Vectors: Addition of vectors, scalar multiplication, dot and cross products, scalar triple products and their geometrical interpretations.

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WHAT IS A PSEUDO FORCE?

 PSEUDO FORCE

STATEMENT:

If a body is at rest or in uniform motion in a straight line it will continue to do so unless compelled by an external unbalanced force.

==>The above statement is valid only when you observe from non-accelerated frames.

==>If you observe the motion from earth , the above statement is valid at earth , so at earth above statement is known as NEWTONsinglequotes FIRST LAW.    


==>Mean above statement is a definition of frame in which law of Inertia is valid and these frames are known as Inertial frames (Non accelerated Frames)
    
==>Means If we are not observing the motion from inertial frame ,above statement will not valid.

==>Such  a frames are known as Non Inertial Frames (Accelerated Frame)

==>Actually Newton Wanted  to apply the above Condition (Give in the Statement) ,So he gives the concept of PSEUDO FORCE.


==>First of all you must know that PSEUDO FORCE is a Imaginary force ,it is not  a real force (Like ,Gravitational force ,Electromagnetic force ).

==> We will understand PSEUDO FORCE  through an .....

EXAMPLE :

                                

==>We have two observers A and B and two boxes A and B .Person B and box B are on Platform (at rest ) and Person A and Box A are in the train (At rest with respect to train).

==>Train is moving towards right with constant acceleration .

==>Now we will observe Boxes A and  B from two frames (train and Platform)

            

You can observe that from trainsinglequotes frame  is not valid(Quantitative relation between      and  , as said in NEWTONsinglequoteS first law).

=> Note 

You must know that Real Force on box A in the horizontal direction is static friction (f_s) and  is acceleration of train .

=>Newton introduced PSEUDO force so that one could apply   , even from accelerated frames(Non Inertial Frames)

=>SEE HOW : 

If person A observe Box A...........
        , From expression (1)

                                        

Note:

(-) Sign shows that  is towards left.

==>Now you can observe PSEUDO FORCE when person (A) observe box (B)

            
 
In this way we can understand How to apply PSEUDO force.

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