Physics

	Wavelength (m)	Frequency (Hz)	Energy (J)
Radio	> 1 x 10-1	< 3 x 109	< 2 x 10-24
Microwave	1 x 10-3 - 1 x 10-1	3 x 109 - 3 x 1011	2 x 10-24- 2 x 10-22
Infrared	7 x 10-7 - 1 x 10-3	3 x 1011 - 4 x 1014	2 x 10-22 - 3 x 10-19
Optical	4 x 10-7 - 7 x 10-7	4 x 1014 - 7.5 x 1014	3 x 10-19 - 5 x 10-19
UV	1 x 10-8 - 4 x 10-7	7.5 x 1014 - 3 x 1016	5 x 10-19 - 2 x 10-17
X-ray	1 x 10-11 - 1 x 10-8	3 x 1016 - 3 x 1019	2 x 10-17 - 2 x 10-14
Gamma-ray	< 1 x 10-11	> 3 x 1019	> 2 x 10-14

SRILANKA BROADCASTING CORPORATION BROADCASTS ITS PROGRAMME ON THE 25M BAND.THE FREQUENCY OF BROADCASTING IS 12 MEGA HERTZ

DIMENSION'S OF PLANCK'S CONSTANT ARE SAME AS DIMENSIONS OF ANGULAR MOMENTUM

CYCLE TUBES WELL INFLATED AND LEFT IN SUN BRUST OPEN BECOS THE VOLUME OF AIR INSIDE THE TUBE INCRESES DUE TO RISE IN ITS TEMPERATURE


GALVANIZED IRON IS COATED WITH THIN COATING OF ZINC

SOUND TRAVELS IN ------- VACCUM

LONGEST WAVELENGTH-----VIOLET


THE HEATER ELEMENT IN ELECTRIC IRON IS MADE OF NICHROME

IF WOOLEN CLOTH OF RED COLOUR IS SEEN IN LIGHT OF MERCURY VAPOUR LAMP, THN CLOTH WILL APPEAR BLACK IN COLOUR

RADIANT ENERGY OF SUN RESULTS FROM NUCLEAR FUSION

IMAGE FORMED IN RETINA OF EYE IS REAL AND INVERTED

TRANSVERSE NATURE OF LIGHT IS SHOWN BY POLARISATION OF LIGHT

SURFACE OF WATER IN A LAKE IS JUST GOING TO FREEZE. WHAT IS THE TEMPERATURE OF WATER AT THE BOTTOM-----4 DEGREE C
DENSITY OF WATER IS MAXIMUM AT  4 DEGREE C

IF U FLOAT ON YOUR BACK ON WATER , YOUR WEIGHT IS ZERO

COAL TAR IS THE MOST VISCOUS MEDIUM

IN A BUNSEN BURNER , USE IS MADE OF BERNOULLI'S THEOREM


BOYLE'S LAW

SURFACE TENSION

ARCHEMIDES PRINCIPLE---

RAILWAY TRACKS ARE BANKED ON CURVES SO THAT NECESSARY CENTRIPETAL FORCE MAY BE OBTAINED FROM THE HORIZONTAL COMPONENT OF THE WEIGHT OF THE TRAIN


OIL RISES UP THE WICK IN A LAMP BECOS OF THE SURFACE TENSION PHENOMENON


SPACE TRAVELLOR ON MOON IN DAY LUNAR SKY APPEARS BLACK

THE READING OF CENTIGRADE AND FARENHEIT COINCIDES AT -40 DEGREE

INSTRUMENT CONNECTED WITH THE RECORDING AND REPRODUCTION OF SOUND IS CALLED GRAMOPHONE

A MIRAGE IS THE RESULT OF INCREASE IN REFRACTIVE INDEX OF ATMOSPHERE WITH HEIGHT

HYPERMETROPIA----

POND OF CLEAR WATER APPEARS LESS DEEP THAN IT REALLY IS. DUE TO REFRACTION

SPEED OF LIGHT FIRST MEASURED BY---ROMER

earth's satelitte  IS KEPT MOVING DUE TO CENTRIPETAL FORCE  ---IT IS PROVIDED BY THE GRAITATIONAL ATTRACTION OF EARTH ON THE SATELITTEE

THE PHENOMENON OF RADIOACTIVITY IS ASSOCIATED WITH DECAY OF THE NUCLEUS

CONVERSION OF HEAT INTO ELECTRICAL ENERGY CAN BE ACHEIVED BY USING THERMOCOUPLE

MEN TALKING IN MOON CANNOT HEAR THE SOUND OF EACH OTHER

THEORY OF ELECTROLYSIS-----FARADAY

PRIMARY COLOUR, SECONDARY COLOUR, TERITARY COLOUR

KINETIC ENERGY IS THE ENERGY POSSESSED BY THE BODY BY VIRTUE OF ITS MOTION, POTENTIAL ENERGY IS POSSESSED  BY IRTUE OF ITS POSITION OR SHAPE


WATER IN ALL DIRECTIONS EXERTS PRESSURE

WELDING IS TO JOIN TWO PEICES OF METAL BY RAISING TEMP AT THE JOINT BY MEANS OF EXTERNAL HEAT OF HEAVY ELECTRIC CURRENT SOLDERING IS TO USE AN ALLOY FOR  JOINING METAL


TWO OBJECTS LOSING THE SAME WEIGHT WHEN IMMERSED IN WATER MUST HAVE THE SAME VOLUME

COSMIC RAYS ORIGINATES OUTSIDE THE EARTH

SHORT RADIO WAVES  ARE NOT DANGEROUS

JET ENGINES ARE REACTION ENGINES

MAGNETIC INSTRUMENT CAN BE SHEILDED VERY EFFECTIVELY FROM OUTSIDE fields by placing IT INSIDE A BOX OF SOFT IRON OF HIGH PERMEABILITY.

TEMPERATURE BELOW WHICH A GAS SHOULD BE COOLED BEFORE IT CAN BE LIQUIFIED BY PRESSURE ONLY, IS TERMED AS THE CRITICIAL POINT.


WATER IS USED IN HOT WATER BOTTLES BECOS IT HAS HIGH SPECIFIC HEAT.


A NUMBER OF IMAGES OF A CANDLE FLAME CAN BE SEEN IN A THICK MIRROR. THE BRIGHTEST IMAGE IS SECOND.

HYDROGEN BOMB IS BASED ON PHENOMENON OF NUCLEAR FUSION

THE RATE OF LOSS OF HEAT BY A HOT BODY DEPENDS UPON--ITS RADIATING AREA, ITS TEMPERATURE, ITS NATURE OF RADIATING SURFACE.

COMETS ARE LUMINOUS CELESTIAL BODIES MOVING AROUND THE SUN

IT TAKES LESS TIME TO COOK IN PRESSURE COOKER BECOS THE BOILING POINT OF WATER INCREASES.


THE PROCESS IN WHICH NO HEAT CHANGE TAKES PLACE IS ADIABATIC PROCESS


ENTROPIC PROCESS

TWO PEICES OF GOLD AND SILVER WEIGHING 100 GM EACH IMMERSED IN A LIQUID. THEN THE GOLD PEICE WILL WEIGH MORE


TRANSFORMER IS A DEVICE TO CONVERT LOW VOLTAGE A.C INTO HIGH VOLTAGE
A.C

IN DIESEL ENGINE  THE HIGH TEMPERATURE NEEDED TO IGNITE THE FUEL IS ACHEIVED BY COMPRESSING AIR IN THE CYLINDER.

THE DEVICE USED FOR CONVERTING ALTERNATING CURRENT TO DIRECT CURRENT IS CALLED AS RECTIFIER

WATER PIPES ARE APT TO BURST IN COLD WEATHER BECAUSE THE WATER IN THE PIPE FREEZES INTO ICE AND EXPANDS.

WOOLEN CLOTHES KEEP US WARM BECAUSE THEY PREVENT HEAT OF BODY FROM ESCAPING


A SEXANT USED TO MEASURE HEIGHT OF AN OBJECT

IMAGE OF ANYTHNG SEEN THROUGH ORDINARY LOOKING GLASS IS LATERALLY INVERTED.

THE BOILING POINT OF WATER IS NOT AFFECTED BY TEMPERATURE OF HEAT SOURCE

SCALAR QUANTITY, VECTOR QUANTITY


MAN CIRCLES ROUND THE EARTH IN A SATELLITE THEN HIS MASS REMAINS CONSTANT BUT WEIGHT BECOMES ZERO.

THE COLOUR OF A STAR IS AN INDICATION OF ITS TEMPERATURE

THE DENSE MASS OF SMALL WATER DROPS ON SMOKE OR DUST PARTICLES IN LOWER LAYERS OF THE ATMOSPHERE IS FOG.


WHEN WATER FREEZES ITS DENSITY DECREASES.

FOR STABLE EQUILIBRIUM OF A FLOATING BODY IT IS NECESSARY THAT ITS METACENTRIC SHOULD BE ABOVE ITS CENTER OF GRAVITY.


 

PARSEC----MEASURES ORBITAL VELOCITY OF GIANT STARS
DOUBLE CONVEX AIR BUBBLE IN WATER WOULD BEHAVE AS A DIVERGENT LENS
























































RAINBOW----CAUSED BY DISPERSION


DOPLLER EFFECT---RELATED TO SOUND

AT CONSTANT TEMP THE ,PRESSURE OF GIVEN MASS OF GAS IS PROPORTIONAL TO ITS VOLUME INVERSLY






WILLOWING A CARPET THE DUST IS REMOVED---NEWTON FIRST LAW





ARCHIMEDES----GREECE
ALEXANDER GRAHAM BELL-------BRITAIN
NICOLAS COPERNICUS----POLAND
ALBERT EINSTEIN-----GERMANY





SOUND MAX VELOCITY IN STEEL

RED COLOUR HAS MAXIMUM ENERGY


AIR IS A MIXTURE

NON METAL WITH ELECTRICAL CONDUCTIVITY----GRAPHITE


FIRST INSECTICIDE MANUFACTURED IN INDIA-----BHC



C IS THE VELOCITY OF LIGHT AND y IS THE FREQUENCY OF THE PHOTON, THE MOMENTUM ASSOCIATED WITH THE PHOTON-------hc/y


A DISADVANTAGE OF THE LASER PRINTER IS----NONE OF THE BELOW
IT IS QUIETER THAN AN IMPACT PRINTER
THE OUTPUT IS OF A LOWER QUALITY
IT IS VERY SLOW



THE PROPOGATION OF LIGHT THGH OPTICAL FIBRES IS BASED ON TOTAL INTERNAL REFLECTION




NEWTON'S LAW OF COOLING IS A SPECIAL CASE OF STEFAN'S LAW

PLANCK'S LAW--------------
KIRCHHOFF'S LAW---------
WIEN'S DISPLACEMENT LAW------



PLANIMETER----TO KNOW THE SURFACE AREA ON A MAP

RDX---IS CALLED AS CYCLONITE



J.J. THOMSON----
ROBERT MILLIKAN-----MEASUREMENT OF THE ELECTRONIC CHARGE
EINSTEIN----EXPLANATION OF THE PHOTO ELECTRIC EFFECT
SEEBECK-----THERMOELECTRICITY








THE NET RESISTANCE OF A VOLTMETER SHOULD BE LARGE TO ENSURE THAT IT DOES NOT DRAW EXCESSIVE CURRENT




AN OBSERVOR ON THE GROUND HE COULDNT SEE A SECONDARY BOW WHEN THE SUN'S ATTITUDE IS 54 DEGREE





CRITICAL ANGLE OF GLASS IS 41.8 CALCULATE REFRACTIVE INDEX---1.501

LEAST DISTANCE OF DISTINCT VISION IS 25 CM

ORDER OF MOLECULAR RANGE --- 10 ^-8

OERSTED DISCOVERED MAGNETIC FIELD


COLUMB'S LAW GIVES THE MAGNITUDE OF ELECTRIC FORCE BETWN 2 CHARGES


SPECIFIC HEAT CAPACITY OF MERCURY----138 J/KG/K



HELIOCENTRIC THEORY ---15 AD BY NICOLAUS COPERNICUS


MOVIE FRAME IS DISPLACED THE TIME OF 1/24 SECOND

RELATIVE HUMIDITY-----m/M * 100%


BIFOCAL LENS INVENTED BY BEJAMIN FRANKLIN


WHEN A RADIOACTIVE NUCLUES DISINTEGRATES BY EMITTING A BETA PARTICLE ITS ATOMIC NUMBER INCREASES BY ONE

ASCENDING ORDER OF WAVELENGTH RANGE----RADIO WAVES, MICROWAVES, X-RAYS, GAMMA RAYS


PIT VIPER HAVE SPECIALLY DESIGNED SENSE ORGANS. THEY ARE SITUATED  IN POT  ON EITHER SIDE OF THEIR ON THE FRONT OF ITS FACE


IN HOUSE WE GET 220 VOLTS ALTERNATING CURRENT 220 REPRESENTS EFFECTIVE VOLTAGE

THE VALUES OF COEFFICIENT OF VISCOITY IN OLIVE OIL----0.84 POISE

THE TERMINAL VELOCITY IS ABOUT 200 KM/HR FOR SKY DIVER WITH AN OPENED PARACHUTE


KEPLERS FIRST LAW---LAW OF ORBITS

FLEMING'S RIGHT AND RULE IS USED TO FIND THE DIRECTION OF INDUCED E.M.F


ALPHA RAYS NOT A ELECTRO MAGNETIC IN NATURE

MICROWAVES------MAGNETRON ELECTRONIC DEVICE
INFRARED WAVES-----INCREASED BLOOD CIRCULATION
RADIO WAVES------LONGEST WAVELENGTH
X RAY------RADIOGRAPHY



WHICH HEAVY ELEMENTS/ SUBSTANCE X-RAY CANT THEY PASS THROUGH THE LEAD

MOVING COIL GALVANOMETER BE CONVERTED INTO A AMMETER--BY CONNECTION A SUITABLE LOW RESISTANCE IN PARALLEL

WHEN LIQUID EVAPORATES ITS TEMPERATURE FALLS

WHEN WATER SOLIDIFIES TO ICE----VOLUME INCREASE, HEAT IS RELEASED,TEMP NO CHANGES



IRON--- 480 J/KG/K
ICE--2130J/KG/K
PARAFFIN WAX---2900 J/KG/K
WATER---4180 J/KG/K


PITOT TUBE-------TO FIND THE VELOCITY OF A FLUID IN MOTION

LAPLACE GAVE AN EXPLANATION OF THE SURFACE TENSION ON BASIS OF MOLECULAR THEORY


ULTRA CENTRIFUGES WITH SPEEDS OF THE ORDER OF  5 * 10 ^5  rpm
ARE USED TO CONCENTRATE VIRUS IN SOLUTION

MANGANESE STEEL USED FOR MAKING HELMETS

THE PROJECTION ANGLE IS 45 DEGREE FOR MAXIMUM RANGE

IN INDIA, AN EFFLORESCENT CALLED SAJIMATI

GLASS TYPES----- ORDINARY----ELECTRIC BULB
PERFORANS LIGT-----MICROSCOPE PRODUCTS
PYREX--------AMPOULES
FLINT-----BEAUTY SUBSTANCES


THE APPROXIMATE COMPOSITION OF ORDINARY GLASS IS GIVEN BY THE FORMULA-----NA2 O. CAO. 6SIO2

GASTRIC JUICE---1.0---3.0
SOFT DRINKS----3.0
MILK---6.5
SEA WATER-----8.5



IN EXCESS OF IRON IN OUR BODY LEADS TO  SIDEROSIS


THE OXIDE THAT IS PRESENT IN MAXIMUM PORTION IN CEMENT IS CaO

RESPIRATION IS AN IMPORTANT EXOTHERMIC REACTION



BRONSTED AND LOWRY THEORY

AN ACID IS THE SUBSTANCE THAT HAS THE TENDENCY TO LOSE A PROTON

A BASE IS A SUBSTANCE THAT HAS THE TENDENCY TO ACCEPT A PROTON

BUT ITS NOT  AN ACID IS A SUBSTANCE WHICH GIE HYDROGEN IONS IN ITS AQUEOUS SOLUTION . A BASE IS A SUBSTANCE WHICH GIVE HYDROXYL IONS IN ITS AQUEOUS SOLUTION.



IN THE MANUFACTURE OF NITRIC ACID BY OSTWALD'S PROCESS

WASHING SODA IS USED IN SOFTENING OF HARD WATER

ARTIFICIAL RADIO ACTIVITY IS DISCOVERED BY JOLIOT CURIE, FREDERIC CURIE


IN PLANTS THE USE OF RADIO PHOSPHORUS  P 32 TO DETERMINE THE ABSORPTION RATE OF FERTILIZERS

IF DOSE IN ROENTGEN RANGE IS 600 ABOVE THE EFFECT IS 100% CHANCES OF DEATH



BRASS---CU AND ZN
BRONZE----CU AND TIN
SOLDER-----LEAD AND TIN
TYPE METAL----ANTIMONY, LEAD AND TIN


1986----RUSSIA CHERNOBYL NUCLEAR ACCIDENT



CONTROL RODS----CADMIUM
MODERATOR------ GRAPHITE
COOLANT-------LIQUID SODIUM

ACIDS----THEY ARE SOUR IN TASTE, THEY TURN BLUE LITMUS RED, SOLUTIONS CONDUCT ELECTRICITY,  REACT WITH BASES TO FORM SALT AND WATER








































ELEPHANT WILL PRODUCE AND DETECT ULTRASONICS

TEMPERATURE------KELVIN
ELECTRIC CURRENT-----AMPERE
AMOUNT OF SUBSTANCE----MOLE
LUMINOSITY----CANDELA



WAVES PRODUCED ON THE SURFACE OF WATER-----TRANSVERSE


CONCAVE IS USED TO OBTAIN REAL IMAGE OF THE SIZE


HARMONIC SERIES IN OPEN ORGAN PIPE-------1:2:3





MELTING PT OF MERCURY------  -39 DEG C
FREEZING PT OF ALCHOL------  -117 DEG C
ABSOLUTE ZERO-----    -273 DEG C
PLATINUM MELTING POINT-------    2045K


60 DEG C  = 333K


CAESIUM -133    WIDELY USED IN ATOMIC CLOCKS

NON CONVENTIONAL SOURCE OF ENERGY ---GEOTHERMAL

THE RENEWABLE SOURCE OF ENERGY--- TIDAL WAVE


WHAT FORCE WOULD BE NEEDED TO PRODUCE AN ACCELERATION OF 1 m/s on a ball of mass 1kg------ 1N

ACTION AND REACTION DO NOT BALANCE EACH OTHER BECOD THEY ACT ON DIFFERENT BODIES


THE NORMAL VALUE OF ACCELERATION DUE TO GRAVITY IS 9.8M/S2

A MOTOR VEHICLE TRAVELS 180 KM IN 3 HRS. FIND ITS VELOCITY---16.6 M/S

LEAST COUNT OF VERNIER CALIPER ------0.01CM


THE INTERNATIONAL SYSTEM OF UNITS IS THE VERSION OF THE METRIC SYSTEM ESTABLISHED BY AN WORLD AGREEMENT ------1971





















PRINCIPAL FOCUS OF A SPHERICAL MIRROR IS BETWEEN P AND C


ONE MACH IS EQUAL TO VELOCITY OF AN OBJECT TRAVELLING WITH THE VELOCITY SOUND 340 m/s

the ideal gas equation is pv=t constant

the maximum displacement of a particle in the upward direction is crest

THE AUDIO TAPE IS A STRIP OF PLASTIC COATED WITH CHROMIUM DI OXIDE

                                            Physics

I.FUNDAMENTALS

-PHYSICAL QUANTITIES ARE DIVIDED INTO----1.FUNDAMENTAL  2.DERIVED

FUNDAMENTAL QUANTITIES----LENGTH , MASS, TIME

DERIVED QUANTITES----ARE BASED ON THE OTHER PHYSICAL QUANTITIES

EG: SPEED, DENSITY,…

-PHYSICAL QUANTITIES ARE DIVIDED INTO 2 CLASSES 1. SCALAR, 2.VECTOR

SCALAR--- HAS ONLY MAGNITUDE EG: MASS, SPEED,TIME

VECTOR—HAS MAGNITUDE AND DIRECTION.EG: VELOCITY, ACCELERATION,FORCE

IN 1960, THE GENERAL CONFERENCE OF WEIGHTS AND MEASURES RECOMMENDED

THAT METRIC SYSTEM OF MEASUREMENT CALLED INTERNATIONAL SYSTEMS OF UNITS (SI UNITS) ,TO USE IT UNIVERSALLY.

UNIT OF LENGTH

SI UNIT OF LENGTH- m

ASTRONOMICAL DISTANCES

1 LIGHT YEAR= 9.46*10 POWER OF -15 m , USED TO MEASURE DISTANCE OF STARS

1 ASTRONOMICAL UNIT= 1.495*10 POWER OF 11 m , MEAN DISTANCE FROM CENTRE OF EARTH TO CENTRE OF SUN

1 PARSEC= 3.084*10 POWER OF 16 m, DISTANCE AT WHICH A.U SUBTENDS AN ANGLE OF ONE SECOND OF ARC

UNIT OF MASS

SI UNIT OF MASS KG

1 TONNE= 10,000KG

UNITS

1. Length - Metre

2. Mass - Kg

3. Time - Second

4. Current - Ampere

5. Temperature - Kelvin

6. Luminous intensity - Candela

7. Amount of substance - Mole

8. Plane angle - Radian

9. Solid angle - Stradcan

Derived Units

1. Area – (Metre)2

2. Velocity – Metre/Second

3. Accelaration – Metre/Second2

4. Density – Kg/m3

5. Weight – (mg)kg

6. Momentum – kgm/sec

7. Pressure – Pascal (Newton/m2)

 8. Force(ma) – Newton

9. Energy – Joule

10. Work – Joule or Newton/meter

11. Moment of force – Force x distance

 12. Heat Capacity – Joule/k

13. Specific heat capacity – Joule/kg/k

14. Power – work/time (watt)

15. Kinetic energy – ½ mv2

16. Potential energy – mgh

17. Mechanical advantage – Load/Power

 18. Efficiency of engine – Mechanical advantage/velocity ratio x 1005

19. C = (F – 32) 5/9 20. k = C + 273

21. Absolute zero – -273C 0K

22. Celsius equal to Farenheit at - -40

23. Power of lens – Dioptre

 24. Intensity of light, Wavelength of Light– A or Nanometer

25. Intensity of sound – Decibel

26. Frequency – Hertz

27. Wavelength – Metre

28. Velocity of Sound – metre/sec (330m/s)

29. Magnetic pole strength – Amperemetre

30. Magnetic moment – Ampere metre2

31. Permeability – Henry/metre

32. Potential difference – Volt

33. Electrical Conductivity – Mho

34. Electrical Resistance – Ohm

35. Electric Charge – Column

36. Electrical Capacitance – Farad

37. Electrical Inductance – Henry

38. Energy of Electron – Electron volt

39. Atmospheric pressure – Bar (1 Bar = 76mmHg)

40. Distance used in navigation – Nautical Mile (6080 feet) or 1837 m

41. Depth of Sea – Fathom (1 Fathom = 6feet)

42. Speed of supersonic flight – Mac No (One Mac No = 760 miles per hour)

43. Parsec (Largest unit to measure distance between celestial bodies) – 3.2light years.

44.RELATIVE DENSITY- NO UNIT

BRITISH SYSTEM OF UNITS(F.P.S)

UNIT OF LENGTH IS FOOT, UNIT OF MASS IS POUND, TIME IS SAME

1 FOOT = 0.3048 m

1 POUND = 0.4536 kg

MOTION

MECHANICAL MOTION 2 TYPES---1. ROTATIONAL (SPIN) AND  2. TRANSLATIONAL(LINEAR)

CONCEPTS IN MOTION-

SPEED— SCALAR QUANTITY

SPEED=DISTANCE/TIME

UNIT= m/s

VELOCITY—VECTOR QUANTITY

SPEED IN A SPECIFIC DIRECTION. UNIT IS m/s

ACCELARATION—(ZERO AT THE CENTRE OF THE EARTH)

RATE OF CHANGE OF VELOCITY. VELOCITY/TIME.. UNIT=m/s*s

ACCELERATION IS USED IF VELOCITY INCREASES, IF IT DECREASES THEN DECELERATION OR RETRADATION IS USED.

ACCELERATION DUE TO GRAVITY

A BALL DROPPED FROM TOP OF THE  BUILDING---

ITS ACCELERATION DUE TO GRAVITY IS ALWAYS SAME g=9.8m/s2

Its velocity changes

EQUATIONS OF MOTION

  v=u+at

  S=ut+ 1/2at2

  v2-u2=2as

WHEEL BARROW SECOND ORDER LEVER EXAMPLE

Force

NEWTON’S LAW OF UNIVERSAL GRVITATION

F=G m1m2/r2

G= 6.67*10 POWER OF -11

VISCOUS FORCE IS DIRECTLY PROPORTIONAL TO VELOCITY GRADIENT

CENTRIPETAL FORCE

CENTRIFUGAL FORCE

WEIGHT= MASS*g

FRICTION

Air friction is much less than liquid… i.e hovercraft less frictional force than boat
any moving object on earth finally comes to rest by friction

NEWTON’S LAW OF MOTION

FIRST LAW

MOMENTUM= MASS* VELOCITY

SECOND LAW

F=ma

THIRD LAW

IMPULSE

CHANGE IN MOMENTUM= FORCE * TIME (IMPULSE)

CRICKETER CATCHING THE BALL

WORK ---SCALAR

FORCE*DISTANCE

SI UNIT—JOULE

POWER

WORK DONE /TIME TAKEN

SI UNIT-W (watt)

Energy

CAPCITY TO DO WORK

UNIT OF ENERGY----JOULE

KINETIC ENERGY

K.E= ½ mv2

POTENTIAL ENERGY

P.E=mgh

Conservation of energy

SURFACE TENSION----OIL POURED ON THE SURFACE OF WATER ITS SURFACE TENSION DECREASES.

COHESIVE FORCE

ADHESIVE FORCE

SURFACE TENSION

CAPILLARITY---BLOTTING PAPER ABSORBS INK BECOS OF CAPILLARY ACTION

HEAT

SALT ADDED TO ICE DECREASES THE MELTING POINT

WAVE MOTION

ELECTRO MAGNETIC RADIATION

LIGHT

PROPAGATION OF LIGHT THGH OPTICAL FIBRES IS BASED ON TOTAL INTERNAL REFLECTON

DIGITAL CAMERA IS AN INPUT DEVICE MAINLY USED TO CONVERT IMAGES.

WHEN LIGHT IS  PASSED THROUGH CRYSTAL DOUBLE REFRACTION OCCURS CALCITE (CALCIUM CARBONATE)

FOCAL LENGTH OF 2 LENS IN CONTACT=1/F=1F1+1/F2

Some representative refractive indices
Material	λ (nm)	n	Ref.
Vacuum		1 (per definition)
Air at STP		1.000277
Gases at 0 °C and 1 atm
Air	589.29	1.000293	[1]
Carbon dioxide	589.29	1.00045	[2] [3] [4]
Helium	589.29	1.000036	[1]
Hydrogen	589.29	1.000132	[1]
Liquids at 20 °C
Arsenic trisulfide and sulfur in methylene iodide		1.9	[5]
Benzene	589.29	1.501	[1]
Carbon disulfide	589.29	1.628	[1]
Carbon tetrachloride	589.29	1.461	[1]
Ethyl alcohol (ethanol)	589.29	1.361	[1]
Silicone oil		1.52045	[6]
Water	589.29	1.3330	[1]
Solids at room temperature
Titanium dioxide (also called Titania or Rutile )	589.29	2.496	[7]
Diamond	589.29	2.419	[1]
Strontium titanate	589.29	2.41
Amber	589.29	1.55	[1]
Fused silica (also called Fused Quartz)	589.29	1.458	[1]
Sodium chloride	589.29	1.544	[8]
Other materials
Liquid helium		1.025
Water ice		1.31
Cornea (human)		1.373/1.380/1.401	[9]
Lens (human)		1.386 - 1.406
Acetone		1.36
Ethanol		1.36
Glycerol		1.4729
Bromine		1.661
Teflon		1.35 - 1.38
Teflon AF		1.315	[10]
Cytop		1.34	[11]
Sylgard 184		1.43
Acrylic glass		1.490 - 1.492
Polycarbonate		1.584 - 1.586
PMMA		1.4893 - 1.4899
PETg		1.57
PET		1.5750
Crown glass (pure)		1.50 - 1.54
Flint glass (pure)		1.60 - 1.62
Crown glass (impure)		1.485 - 1.755
Flint glass (impure)		1.523 - 1.925
Pyrex (a borosilicate glass)		1.470	[12]
Cryolite		1.338
Rock salt		1.516
Sapphire		1.762–1.778
Sugar Solution, 25%		1.3723	[13]
Sugar Solution, 50%		1.4200	[13]
Sugar Solution, 75%		1.4774	[13]
Cubic zirconia		2.15 - 2.18
Potassium Niobate (KNbO3)		2.28
Moissanite		2.65 - 2.69
Cinnabar (Mercury sulfide)		3.02
Gallium(III) phosphide		3.5
Gallium(III) arsenide		3.927
Zinc Oxide	390	2.4
Germanium		4.01
Silicon	590	3.96	[14]

 

SOUND

PITCH AND FREQUENCY

LOUDNESS

SPEED OF SOUND

REFLECTION OF SOUND, ECHO

REFRACTION OF SOUND

RESONANCE

DOPPLER EFFECT

SONIC BOOM

MUSIC SCALE

NOISE REDUCTION  IN RECORDING MEDIA

Uses

SONAR—USED BY NAVIGATORS


HYDROPHONES----USED TO LISTEN AND RECORD UNDERWATER SOUNDS

MAGNETISM

STATIC ELECTRICITY

What causes power grid failure?

2012-08-02 20:08:07 puneet

Recently, East, North and North-East regions of India went through a severe

blackout for several hours after the sudden collapse of the northern grid.

This article endeavors to answer some general questions pertaining to Power grid.

What constitutes a Power grid?

An electricity or power grid is a network of power lines that withdraws electricity from

a generating station. It has 3 main constituents:

Generating stations- The electric power generated is enhanced to a higher

voltage-at which it connects to the transmission network.

Transmission lines - The transmission network will carry the power long

distances–often across state lines, and sometimes across international

boundaries, until it reaches its wholesale customer (usually the company that

owns the local distribution network).

Substations - Here, the power is reduced to a lower voltage—from a

transmission level voltage to a distribution level voltage. As it leaves the

substation, it enters the distribution wiring. Finally, upon arrival at the service

location, the power is stepped down again from the distribution voltage to the

required service voltage(s).

How does it function?

The grid functions in a narrow frequency band of 49.5Hz to 50.2Hz.

The frequency and voltage of the grid is monitored by the load dispatch center

on the basis of the drawl schedule of the respective states of every region.

When there is excess drawl or less generation of power the grid frequency

falls and it increases when there is excess supply or the less drawl.

What is the reason behind grid collapse?

A grid fails when the frequency plunges below the lower limit of the (49.5-

50.2Hz) band or shoots up beyond the upper limit.

As a result, transmission lines stop accepting power supply and other grid

constituents, including the generating stations go out of order.

How is it restored?

Power restoration is a complicated process which involves all the grid

constituents.

The grid management authorities start restoring the transmission lines and at

the same time make alternative arrangements for electricity supply.

Generating stations are restarted.

Among all power projects, coal-based plants take the longest to resume

operations.

How is the fault detected?

The task is difficult as the authorities have to analyze the details of per-second

consumption and supply by each constituent of the grid at the time of the

failure.

As a regular exercise, the regional load dispatch center authorities keep

warning states and regulatory authorities at regular intervals about possible

collapse due to over drawl or less drawl of electricity

ELCTRICITY BY FRICTION

LIGHTINING CONDUCTOR

INSULATORS

CONDUCTORS

SUPERCONDUCTORS

SEMICONDUCTORS

TRANSISTORS

INTEGRATED CIRCUITS

CURRENT ELECTRICITY

GENERATOR IS A DEVICE TO CONVERT MECHANICAL ENERGY INTO ELECTRIC ENERGY

Galvanometer converted into voltmeter by connecting high resistence in series

Galvanometer converted into ammeter by connecting low resistence in parallel

ELECTRIC CURRENT---FLOW OF ELECTRIC CHARGE

ELECTRO MOTIVE FORCE--- PROVIDED BY CELL IS ESSENTIAL TO MAINTAIN A CONTINUOUS FLOW OF CURRENT IN CIRCUIT

ELECTRIC RESISTANCE

CURRENT FLOWS THROUGH CONDUCTOR IT OFFERS SOME OBSTRUCTION TO THE CURRENT.TIHS OBSTRUCTION IS CALLED ELECTRIC RESISTANCE,IT DEPENDS ON LENGTH(l) AND AREA OF CROSS SECTION( a), p IS THE CONSTANT RESISTIVITY.

R=pl/a

ELECTRIC CELL

EFFECTS OF ELECTRIC CURRENT—

MAGNETIC EFFECT

CHEMICAL EFFECT

ELECTROPLATING

HEATING EFFECT

MOTOR EFFECT

LOUDSPEAKER

MICROPHONE

ELECTRIC GENERATOR(DYNAMO)

INVERTER

POWER GENERATION AND TRANSMISSION

TRANSFORMER

DOMESTIC ELECTRIC INSTALLATION

FUSE--- FUSE WIRE IS A WIRE OF HIGH RESISTANCE AND LOW MELTING POINT.

TIN AND LEAD USED AS SOLDERING MATERIAL

EARTH--- TO SAFEGAURD AGNT SHOCKS

FLEXIBLE CABLES---RED OR BROWN (LIVE CONNECTION), BLUE OR BLACK(NEUTRAL CONNECTION) GREEN OR YELLOW(EARTH CONNECTION)

 PLUGS, SOCKETS SWITCHES

ELECTRIC LIGHT

ATOMIC PHYSICS

METALS MORE FREE ELECTRONS

HYDROGEN BOMB—PRINCIPLE OF NUCLEAR FUSION

NUCLEAR PHYSICS

ISOTOPES- SAAME ATOMIC NUMBER DIFF MASS NUMBER

RADIOACTIVITY

UNSTABLE NUCLEI DISINTEGRATES AND EMITS ALPHA ,BETA AND GAMMA RAYS

ALPHA—POSITIVELY CHARGED HELIUM NUCLEI

BETA- NEGATIVELY CHARGED ELECTRONS

GAMMA—CHARGELESS PHOTONS

ALPHA,BETA,GAMMA  ALL AFFECT THE PHOTOGRAPHIC PLATE

KLYSTRON PRODUCES MICROWAVES

X-RAYS CANT PASS THGH GOLD

laws--

kepler's law----motion of planets around sun





VENTURIMETER----MEASURE RATE OF FLOW OF FLUIDS

TERMS

HALF LIFE—TIME TAKEN FOR HALF THE NO OF ATOMS TO DIS INTEGRATE

TRANSMUTATION- CHANGING ONE ELEMENT INTO ANOTHER

RADIOACTIVE ISOTOPES

USES

FUEL CELLS ARE USED IN SPACE  CRAFTS

ASTRONOMY AND SPACE SCIENCE

1. Astronomy is the study of the heavenly bodies

2. Giant clusters of stars are called Galaxies

3. Megullonic clouds are Galaxies

4. Our sun belongs to Milky Way

5. Milky way is spiral shaped galaxy

6. The sun is about 30,000 light years from the center of the galaxy

7. The diameter of the Milky Way is nearly 1,20,000 light years

8. The spectra of light from these galaxies show a frequency shift towards the red

known as the ‘red shift’

9. Red shift indicates that the galaxies are moving away. It is due to Doppler Effect

10. All galaxies burst out from a single point.

11. This explosion that resulted in the expansion of the universe is called Bre Bang

12. The age of the Universe is estimated to be around (1-2) * 1010 years

13. Nebulae are cloudy, luminous patches in the heaven consisting of clusters of stars

and gaseous cloud. These are a number of nebulae within the Milky Way itself

Stars are formed out of condensing gases within these nebulae

14. One can note that Stars within certain groups are so arranged as to look like

familiar objects or animals. These groups are called constellation.

15. E.g., Vrsa Major (Great Bear), Ursa Minor (Little Bear). Orion (Giant Hunter).

Cygnus (Swan), Hydra (Sea Serpent) are Constellations.

16. It is interesting to note that Vega is a brightest Star in the constellation Lyra

17. Vega would be the second star to have planets. The first of course being the sun.

18. There are 89 constellations; Hydra is the largest of these.

19. In Universe, certain objects appear smaller than any galaxy, yet they emit more

energy than all the stars of the Milky Way. Since they resembled stars. They were

called quasars

20. The north can be identified using the pole star by the ship mariner

21. If we look at the northern sky, at an elevation equal to the latitude of our place.

We will be able to locate the pole star.

22. Stars are formed out of the condensing gases within the Nebulae which form part

of most galaxies.

23. The condensing process goes on, until the star is without shrinking further and the

central part of the star become so hot that fusion reaction start and the star emits

radiation into space.

24. The process of the death of a star begins, when fuel in its core run out.

25. The collapsing core, during the death of star, imparts so much energy to the

exterior of the star that it explodes with an increase in its luminosity 10000 times

or even more. This stage is referred to as super nova explosion.

26. After the supernova explosion, the highly dense residual core of the small star is

called a white dwarf.

27. A star with a mass of less than 1.4 solar masses will end its life as a white dwarf.

This is called the Chandrasekhar limit.

28. The extremely dense core left after the explosion of a bigger star is known as

neutron star.

29. Neutron stars spin very fast while spinning. Neutron stars radiate all kinds of

electromagnetic radiations. When this happens, the star is known as a pulser.

30. Bigger star (mass greater than 5 solar masses) are believed to end up as black hole

after the explosion.

31. The gravitation field of a black hold is believed to be so intense that no matter or

radiation can escape from it.

32. The sun is our nearest star. The sun is a hot spheres of gas – 74% hydrogen. 25%

helium and 1% other elements

33. The sun as it is visible to us is actually the photosphere. The photosphere has a

surface temperature of 5800 K.

34. The Chromo sphere is the solar atmosphere just above the photosphere. The

temperature in the Chromospheres rises from 4300 K to above 4,00,000 K

35. The Corona is the outermost layer of the sun. It is very hot. The rise of its

temperature is even upto 50000 K.

36. There are nine planets revolving around the sun. Compared to the sun, the planets

are quite small and relatively cool. They are not self-luminous.

37. In order of their proximity to the sun, these are Mercury, Venus, Earth, Mars,

Jupiter, Saturn, Uranus, Neptune and Pluto

38. Mercury is nearer to the Sun and it is too hot. It is a very small planet. It has no

satellites.

39. Venus appears to be the brightest of all the planets. Venus along with Neptune

revolves in almost circular orbit. All other planet revolves in elliptical orbit.

Venus along with Mars has more Carbon di oxide in their atmosphere. It has no

satellite.

40. Earth takes 365 days for its one revolution and 24 hrs for its one rotation. It is

fifth in the size of planets. Earth’s atmosphere contain 79% Nitrogen, 20%

Oxygen, 1% Argon, 0.03% Carbon-di-oxide etc.

41. Moon, the only satellite of Earth takes same time for its rotation and revaluation

so, we can see only one face (59%) of the moon

42. Mars is called as Red Planet. It has 2 satellites (moons). They are Phobas. Tumas

43. Jupiter is the biggest planet. It has 16 moons. Ganymede, Callisto, Europa, lo are

the moons of Jupiter. Ganymede is the largest satellite in solar system.

44. Saturn has very prominent rings around it. It has 22 satellites. It has a great

gravitational pull. Titan, Zapetus, Dione, Rhea and Tethys are the satellites of

Saturn. Titan of Saturn is the second largest moon.

45. William Sharshal discovered Uranus.

46. Pluto is the farthest planet. It is the coolest and smallest planet of solar system. It

has one moon. It is the coolest.

8

47. The earth’s age is estimated to be 4.6 * 109 years.

48. In the belt, which lies between Mars and Jupiter, there are thousands of minor

planets called asteroids. Ceres, the largest known asteroid has a diameter of any

about 1000 km.

49. As a result of collision between two asteroids, a small lump of material may be

thrown off. When such lumps enter the earth’s atmosphere, they produce blazes of

light. Some of the earth’s surface is called meteorites.

50. Comets are the debris left over from the formation of the outer planets. They orbit

elliptically in the solar system.

51. A comet has a central core of icy material. When a comet comes nearer to the sun,

the light from the sun affects the head icy region. A portion of the gas leaves the

head altogether forming tail, which always points away from the sun.

52. The period of Halley’s comet is 76 years. Its 33rd appearance was February 9th

1986.

53. Since a comet loses its icy material by evaporation, it ends up in small chunks and

tiny sand-like particles. These chunks and tiny-sand like particles keep orbiting

the sun. when such particle enters the earth’s atmosphere, it evaporates almost

immediately and produces trail of hot gas often visible at night. These are meteors

or shooting stars.

54. Sputnik – 1 is the first artificial satellite launched by the USSR in 1957

55. The US space probe ‘Voyager’ transmitted very clear pictures of Neptune. These

pictures showed six moons around Neptune.

56. The USA developed the Strategic Defence Initiatives (SDI) programme dubbed as

star wars system. If successful, this system will be capable of destroying enemy

nuclear warheads on ground or in space, before they reach their targets.

57. Troposphere is the lower most layer of atmosphere. Mountains, Clouds, rains are

present in this space. 9/10 of total air is in this region. This region covers upto 15

kms from the earth.

58. Stratosphere is the second Layer. This region covers from 15 to 75 kms above the

earth. It is the region of constant temperature, constant horizontal winds with very

little air. It is difficult to breath here. Explorations are done with balloons. The

Ozone layer is in this region.

59. Ionosphere is the next Layer. This region comes from 75 to 250 km above the

earth. Exploration is done with sounding rockets. The sky is black even when the

sun is shinning. Radio waves are reflected from this region.

60. Exosphere is the Top Layer of atmosphere. This region covers from 250 to 900

km above the earth. No gases or air is in this region which is very dark.

61. In 1981, India too successfully put into orbit is first experimental geostationary

communication satellite, Apple, launched in French Guyana.

62. The ionosphere consists of two layers of ionized air. The outer one is 200

kilometers from the earth and is known as the Appleton layer named after its

discoverer.

63. Aryabatta is the first Indian satellite named after the great Indian astronomer of

the 5th century AD as launched from Russian Cosmodraome on April 19, 1975.

9

64. Cosmic Rays are extremely high-energy high-speed proton capable of causing

severe burns or even death. Invented by Millican.

65. Explorer I was the first United States artificial satellite to enter earth’s orbit on

31st January 1958. It was responsible for the discovery of the Van Allan radiation

belts.

66. The Star (other than the sun) nearest to the earth is proximate century.

67. The nearest star (other than the sun), which is visible to the naked eye is Alpha

Centuari

68. Mars is the red planet. Mercury is the closest planet and the hottest planet. Venus

is the brightest planet. Pluto is the farthest Planet. Jupiter is the biggest Planet.

Mercury and Venus do not have planet.

69. Stars appear to move from east to West because the earth is rotating from west to

east.

70. On the moon, an astronaut cannot drink lemonade with the help of straw. Because

there is no atmosphere on the moon.

KEPLERS LAWS OF MOTION

FIRST LAW (LAW OF ORBITS)

PERIGEE(A), APOGEE (L)

SECOND LAW (LAW OF AREAS)

THIRD LAW (LAW OF PERIODS)

T2DIRECTLY PROPORTIONAL TO R3

R-MEAN DISTANCE OF PLANET FROM SUN

T-PERIOD OF REVOLUTION

SATELLITES

FIRST ARTIFICIAL SATELITTE LAUNCHED IN 1956 IS SPUTNIK BY USSR

INDIA LAUNCHED 1^ST SATELITE  ARYABHATTA IN 19,APRIL,1975.

S- BAND 2GHZ TO 4 GHZ

IN A BAROMETER MERCURY IS PREFERRED OVER WATER BECOS MERCURY HAS HIGH DENSITY AND LOW VAPOUR PRESSURE

Longitudinal waves do  not exhibit--- polarization

Diamagnetic material—

Sound travels fastest in iron

Moderator in nuclear reactor--- heavy water

Coolant--water

MOST SIGNIFICANT REVOLUTION IN PHYSICS IN 20^TH CENTURY IS QUANTUM MECHANICS

ELECTRIC BULB FILAMENT--- MADE OF TANTALUM, OSMIUM, TUNGSTEN  NOT POSSIB BY NICHROME.

SUPER CONDUCTIVITY RESULTS WHEN MATTER COOLED TO VERY LOW TEMP

DEBROGILE WAVELENGTG

DIFF BETWN NUCLEAR REACTOR AND ATOMIC BOMB—THE CHAIN REACTION IN NUCLEAR REACT IS CONTROLLED.

ASTIGMATISM—CYLINDRICAL LENS

CATARACT—OBJECT IN LENS

HYPERMETROPIA---CONVEX LENS

MYOPIA—CONCAVE LENS

CONVEX MIRROR—REAR VIEW COS ERECT IMAGE AND SMALL SIZE

Long sight—convex

Principle behind submarine—archemedis

Electric capacity--faraday

Electric current-ampere

Electromotive force-volt

Electric resistance-ohm

Mass energy relation—einstein

Energy of photon—planck

Uncertainity principle-heisenberg

Spin multiplicity---pauli

AT -40 DEGREE THE READINGS OF CENTIGRADE AND FAHRENHEIT ARE THE SAME

CHARGE OF ELECTRON—1.6810 POWER OF -19 C

27 DEGREE C EXPRESSED AS 300K

RELATION AMONG VELOCITY,FREQUENCY,WAVELENGTH --- V=n

SPECIFIC VOLUME OF WATE MINIMUM AT  4 DEGREE C

I KILO WATT HOUR---3.6*10,OOOOOO JOULE

VALUE OF UNIVERSAL GRAVITATIONLA CONSTANT—6.67*10 POWER OF -11 NM2 KG-2

Newton--- laws of gravitation

Galileo—moons of Jupiter

Kepler- laws of planetary motion

KEPLERS SECOND LAW- LAW OF AREAS

Copernicus-heliocentric theory

Plimsoll line (a line on a ship's hull indicating the maximum safe draft, and therefore the minimum freeboard for the vessel in various operating conditions)

NOISE IS 120 DB

Galvanometer converted in to voltmeter by connecting high resistence in series

Periscope

Spectroscope

Camera

Cinema-persistance of vision(how many sec?

Viscocity-

VISCOCITY OF WATE R IS 0.018 POISE

Surface tension-newton/m

Young’s modulus-

Rigidity modulus-

VOLTMETER—MEAS OF POTENTIAL DIIFF

AMMMETER—MEASUREMENT OF ELEVTRIC CURRENT

GALVANOMETER—DETECTION OF ELECTRIC CURRENT

POTENTIOMETER—MEAS OF E. M. F

TIME OF LIGHT OF PROJECTILE---THROWN AT AN ANGLE---2uSINo/g

TEMP OF FREZZING MIXUTRE OF SALT AND ICE---3:1

THROWING BALL UPWARD ---- ACCELARATION REMains CONSTANT

OPTICAL FIBRES USED IN ENDOSCOPY

CHIMNEY USED IN KITCHEN IS BASED ON CONVECTION

JOULES’LAW

Electromagnetic waves---ELECTRON MICROSCOPE

Xrays

Microwaves

Infrared

Ultraviolet

ELASTIC WAVES—MUSICAL INSTRUMENT

MATTER WAVES—SURGERY USING LASER

LONGITUDINAL WAVES—ACOUSTIC RADAR

SHIP RISES AS IT ENTERS THE SEA FROM RIVER BECOS---DENSITY OF SEA WATER HIGHER THAN RIVER WATER.

Adding little antimony to germanium we get n-type semiconductor

The material in which resistivity becomes zero at low temperature are superconductors

Mho—is unit of conductivity

Gold mixed with copper to make it hard

Petrol is called as black gold

Principle behind hydrogenbomb is nuclear fusion

soft iron used in electro magnets making

 magnectic effect of  current discovered by orsted

electro magnetic induction-- faraday

Problems

The resistance of a wire that must be placed parallel with a 12? Resistance to obtain a combined resistance of 4.    6 ANS

KDM 916 MEANS--- 91.6% PURE GOLD