HUMIDITY

*The amount of water vapour present in air is called
Ans : Humidity
*When humidity occurs, perspiration is 
Ans : Maximum
*Humidity indicates perspiration, dew or fog etc

MELTING POINT

*The process by which a substance is changed from solid state to liquid state is, called
Ans : Melting
*The fixed temperature at which a substance is changed from solid state to liquid state is called 
Ans : Melting point 
*Melting point of ice can be raised by the decrease of
Ans : Pressure

■ MELTING 

*Mercury -    -39 degree C
*Alcohol -    -114 degree C
*Ice -    -0 degree C

BOILING POINT

*When liquid boils and changes itself into vapour at standard atmospheric pressure is called
Ans : Boiling point 
*When pressure increases boiling point 
Ans : Increases 
*Boiling point of water 
Ans : 100°C
*Water inside a pressure cooker boils at a temperature of
Ans : 120°C

SUBLIMATION

*Sublimation is the process of conversion of a solid directly into
Ans: Vapour 
eg : camphor
*Sublimation occurs when boiling point is less than
Ans : Melting point

EVAPORATION

*The process of conversion of liquid into vapour at any temperature 
Ans: Evaporation 
*Evaporation causes 
Ans : Cooling
*Rate of evaporation increases with increase in temperature, surface area and decrease in
Ans : Pressure
*While sweating under a fan we feel cool because of
Ans : Evaporation

BLACK BODY

*A perfectly black body absorbs all types of
Ans : Heat radiations
*Absorption power of perfectly black body is
Ans : 1
*Device used to measure the temperature of Sun
Ans : Pyroheliometer
*Study of high temperature
Ans : Pyrology
*The radiation emitted from a black body is called
Ans : Black body radiation

ELECTRICITY

*The rate of flow of charge through a conductor per second is called
Ans : Current
(Q - Quantity of charge t - charge flowing in second I - current)
*SI unit is of current
Ans : Ampere (A)
*Electric charge was first observed in a substance called
Ans : Amber
*Unit of electric charge
Ans : Coulomb
*1 coulomb (c) = 6.24 x 1018 electrons
*Charge of an electron = 1.6 x 10'19C
*The region which surrounds the electrically charged particles
Ans : Electric field
*The term electricity is coined by
Ans : Gilbert
*Law of electrolysis were formulated by
Ans : Michael Faraday
*The process of splitting up of a chemical substance when an electric current flows through it
Ans : Electrolysis
*A good conductor of electricity
Ans : Mercury
*The capacity of an electric field to do work on an electric charge
Ans : Electric potential
*Pure water is a bad conductor of electricity because pure water does not dissociate into
Ans : Ions
*Electro magnetism was discovered by
Ans : Hans Christian Oersted
*Positively charged particles lose
Ans : Electrons
*Negatively charged particles gain
Ans : Electrons
*Electricity is divided into two
Ans : (1)Static electricity
         (2)Dynamic electricity
*The electric charge built upon a material as a static mode
Ans : Static electricity
*The type of electric charge flows from one point to another through the conductors, cables etc
Ans : Dynamic electricity
*Dynamic electricity are of two types
(a)Alternating current (AC)
(b)Direct current (DC)

ALTERNATING CURRENT (AC)

*It is the continuous flow of current
*It reverse its direction and magnitude with respect to time
*Electricity supplying for domestic use is
Ans : Alternating Current

DIRECT CURRENT (DC)

 
*Unidirectional flow of electric charge
Ans : Direct Current
*It does not reverse its direction with respect to time
*DC is formerly known as
Ans: Galvanic current
*Batteries, solar cells etc produce
Ans : DC
*AC is used more widely than DC
*The device used to convert AC to DC
Ans : Rectifiers
*The device used to convert DC to AC
Ans : Oscillator
*The device which conducts DC but blocks AC is
Ans : Inductor
*When one coulomb charge is carried from one place to another, the work done is called
Ans : Electric potential difference
*SI unit of electrical potential difference is
Ans : Volt
*The e.m.f or potential difference measured in volt is called
Ans : Voltage

OHM'S LAW

*The potential difference (V) is directly proportional to strength of current flowing through a conductor
Ans : VaI 
V = RI
*Property of some crystals to develop an electromotive force when subjected to mechanical stress is called
Ans : Piezo Electricity
*Quartz Crystal in watches work on the principle of
Ans : Piezo Electricity
*Piezo Electricity was discoverd by
Ans : Pierre Curie and Jacques Curie

RESISTANCE

*The property of a material due to which it opposes the flow charge through it
Ans : Resistance
*Unit of resistance is
Ans : ohm
1 siemens = -1/ohm= ohm-1 or mho
*The metal having lowest resistance
Ans : Silver
*The instrument used to control the resistance
Ans : Rheostat
*Nichrome is used as heating element in many appliances because of
Ans : High resistivity Resistance

SUPER CONDUCTIVITY

*Super conductivity was discovered by 
Ans : Kamerlingh Onnes 
*At very low temperature, super conductivity possesses
Ans : Zero resistance 
*A super conductor above 100 K 
Ans : Ceramics

FUSE

*Fuse is used to avoid
Ans : Overloading of current in electric circuit 
*Fuse is made from an alloy of 
Ans : Lead and Tin
*Fuse has low melting point and high resistivity
*When a charged body is connected to the earth it gets neutralised. It is called 
Ans : Earthing
*A number of cells connected together are called
Ans: Battery
*A source of emf containing two or more cells is called 
Ans: A battery
*Rechargeable batteries like mobile phones torches uses
Ans : Nickel and Cadmium 
*The negative electrode in a drycell is 
Ans : Cathode 
eg : zinc
*The positive electrode in a drycell is
Ans : Anode
eg: carbon rod 
*Cell was first invented by 
Ans : Alessandro Volta 
*Cell is otherwise known as 
Ans : Voltaic Cell 
*Dry cell was invented by 
Ans : Carl Gassner
*In primary cell, chemical energy is converted into
Ans : Electrical energy 
eg : Daniel cell, Dry cell etc 
*Potential difference measured in volt is called
Ans : Voltage
*Colour of positive wire in domestic circuits
Ans : Red / Brown
* Colour of neutral wire in domestic circuit
Ans : Black/Blue
*Colour of earth wire in domestic circuit
Ans : Green

EMF (ELECTROMOTIVE FORCE)

*The electrical potential for a source in a circuit is called 
Ans : EMF
*The emf of a voltaic cell 
Ans : 1 volt 
*Emf of mercury cell 
Ans : 1.35 volt
*The emf of a dry cell
Ans : 1.5volt
*Voltage of a torch cell
Ans : 1.5volt
*Emf of Lithium ion battery
Ans : 3.6volt

ELECTRICAL POWER TRANSMISSION

*The rate of production of electrical energy per unit time
Ans : Electric power
*Electricity supplied for domestic use is
Ans : Alternating Current (AC)
*Electricity for domestic purpose is measured in
Ans : Kilowatt hour (Kwh)
*Kilowatt hour is commonly called as
Ans : Units
1 KWh = 1000 watt x 3600 seconds
*The commercial unit of electrical energy is also
Ans : KWh
*The technique used in the electric circuits in household purpose to protect appliances
Ans : Short Circuiting
*Instrument used to measure the amount of electric energy used by a consumer
Ans : Watt hour meter
*Electric power transmission was developed by
Ans : Thomas Alva Edison
*The supply voltage produced in India
Ans : 11KV (Kilovolt) or 11000 volt
*Voltage range for household purpose 
Ans : 220-230 volt
*The frequency of household electric current in India is
Ans : 50 Hertz

ELECTRONICS

*The study of nature, control and application of electrons
Ans : Electronics
*Vacuum tubes work on the principle of 
Ans : Thermionic emission 
*The simplest form of a vacuum tube 
Ans : Diode
*The device used to convert alternating current (AC) to Direct Current (DC) 
Ans : Rectifiers 
*The device which converts DC energy into AC energy
Ans : Electronic oscillator 
*The process which makes the current to pass in the same direction is called 
Ans : Rectification
*Now thermionic valves are completely replaced by
Ans : Transistors
*Miracle child of electronics 
Ans : Transistor 
*Triode was invented by 
Ans : Lee De Forest 
*Element used in solar cells 
Ans : Silicon

SEMI CONDUCTORS

*Materials whose conductivity lies between conductors and insulators
Ans : Semi conductors
*Examples of semiconductors are
Ans : Germanium, Silicon
*Semi conductor in pure state is called
Ans : Intrinsic Semiconductors
*In intrinsic, number of holes is equal to number of
Ans : Electrons
*The process to improve conductivity 
Ans : Doping
*Process of adding controlled impurities to a pure semiconductor is known as 
Ans : Doping
*The substances used for doping 
Ans : Dopants
*An intrinsic semiconductor undergoes doping, change into
Ans : Extrinsic semiconductor 
*Extrinsic are of two types:
(1)N-type semiconductor
(2)P-type semiconductor In N-type, charge carriers are
Ans : Electrons
*An intrinsic semiconductors have
*Trivalent impurity (eg: Boron, Gallium)
*Pentavalent impurity (eg: Antimony, Arsenic)



■

SEMI CONDUCTORS ARE USED MAINLY IN

 
* Solar cells (silicon)    *transistors
*diodes    *Integrated circuits (IC)

DIODE

*The electronic device which has semiconducting property that allows current to flow in one direction 
Ans : Diode
*Diode is mostly used to convert 
Ans : AC to DC 
*Diode is used as a 
Ans : Rectifier
*Zener diode is used as 
Ans : Voltage regulator

TRANSISTOR

*A semiconductor device used to amplify or switch electronic signals and electrical power
Ans : Transistor
*Transistor is operated at low temperatures and voltages.
*Three regions of a transistor
Ans : Emitter, Base, Collector 
*Transistor transfers a signal from a low resistance to
Ans : High resistance 
*Transistor was invented by
Ans : John Bardeen, W.H. Brattain and William Shockley 
*Electronic intelligene is called 
Ans : ELINT

INTEGRATED CIRCUITS (IC)

*The circuits that act as transistors, diodes, resistors etc is called
Ans : Integrated Circuits 
*'IC' chips are made up of
Ans : Silicon or Germanium 
*IC was invented by 
Ans : Jack Kilby
*IC chip using Silicon was invented by 
Ans : Robert Noyce

GATES

*The electronic circuit which works only on two voltage levels (0 and 1) is called 
Ans : Gates

LOGIC GATES ARE

1. AND Gate 
2. OR Gate 
3. NOT gate
* Universal logics are - NAND, NOR
*Voltage levels In a circuit is either represented by
Ans : '1' or '0'
*The level '1' represents
Ans : High voltage level
*The level '0' represents
Ans : Zero voltage level

TELECOMMUNICATION

*Wireless radio communication was developed by
Ans : Guglielmo Marconi
*First telecommunication device was
Ans : Telegraph
*The frequencies transmitted by TV station is called
Ans : Channel
*For radio transmission BBC uses
Ans : Short waves
*Short waves ranging from 14m to 60m are used for
Ans : International communication
*The waves which travel long distances without loss in intensity
Ans : Short waves (14m to 60m)
*Short waves ranging from 14m to 60m are used for
Ans : International communication
*The waves which travel long distance without loss in intensity
Ans : Short waves (14m to 60m)

VERY HIGH FREQUENCY (VHF)

* Electro magnetic spectrum between 30MHz and 300 MHz is called
Ans:VHF
*VHF is used in
Ans:Radio Transmission and Radar

ULTRA HIGH FREQUENCY (UHF) 

*Frequency ranging from 300 MHZ to 3GHz is called
Ans : VHF
*VHF is used in 
Ans : Ratio Transmission and Rader

ULTRA HIGH FREQUENCY

*Frequency ranging from 300MHZ to 3GHz is called
Ans : UHF
*UHF is used in
Ans : T.V, Communication of satellite etc.
*Telex
Ans : Teleprinter Exchange
*The device used for communicating the text and images through telephone lines
Ans : Fax machine
*The device used to convert audio frequency signals into sound
Ans : Loudspeaker
*The instrument which has ability to convert sound into magnetic energy
Ans : Tape recorder

LCD AND LED

*LCD - Liquid Crystal Display  
*LED - Light Emitting Diode
*LED is used as monitor, clocks, watches, calculators, telephones etc.
*LED was invented by
Ans : Oleg Losev and Nick Holonyak
*Working principle of LED
Ans : Electroluminescence

MAGNETISM

*The phenomenon of attraction of a substance by a magnet is called 
Ans : Magnetism 
*Magnetic substances are
Ans : Iron, Nickel, Cobalt and certain alloys
*A naturally occurring magnet 
Ans : Lodestone
*Magnetism was first discovered in 
Ans : Lodestone
*Every magnet has two poles
Ans : A North pole and a South pole Like poles repel and unlike pole attract
*The field around a magnet where its magnetic effect is felt 
Ans : Magnetic field
*Permanent magnet is made up of 
Ans : Alnico
*Electromagnet is made up of 
Ans : Pure Iron
*Molecular theory of magnetism was proposed by 
Ans : Weber
*The magnetism of a substance decreases while on
Ans : Heating or hammering
*In a magnet the magnetic line of force are from
Ans : North to South pole 
*Artificial magnets made by the use of electricity are called
Ans : Electromagnets
*The instruments which are dependent of magnetic power of electricity are 
Ans : Fan, telephone receiver, dynamo etc
*The scientist who stated that the earth behaves as a huge magnet 
Ans : William Gilbert
*A Magnetic force of attraction at the centre of bar magnet
Ans : Zero
*A coil of insulated wire bound on a rod shaped form made of solid iron is called
Ans : Solenoid
*The unit of magnetic flux density 
Ans : Tesla
*Unit of magnetic flux
Ans : Weber

FERROMAGNETIC SUBSTANCES

*Substances acquire strong magnetism in the direction of magnetic field
Ans : Ferromagnetic substances 
eg: Nickel, Iron, Cobalt 
*Strongest type of magnetism 
Ans : Ferro magnetism 
*Refrigerator magnet is 
Ans : Ferro magnet
*Ferro magnetism was discovered by 
Ans : Louis Neel

PARAMAGNETIC SUBSTANCES

*Substance acquire feeble magnetism in the direction of magnetic field is called 
Ans : Paramagnetic Substances 
eg: Platinum, Oxygen, manganese etc
*Paramagnetic substances is temperature dependent

DIAMAGNETIC SUBSTANCES

*Substances acquire weak magnetism in the direction opposite to the magnetic field is called
Ans : Diamagnetic substances
eg : inert gases, alcohol, copper, gold, water, hydrogen etc.
* Diamagnetic substances is independent of temperature
* Substance used for making electromagnets
Ans : Soft iron
* Electromagnets are used in 
Ans : Electric bells, telephones and telegraphs 

PERMANENT MAGNET

*An object made from a material that is magnetized and creates its own persistent magnetic field is called
Ans : Permanent magnet 
eg: Refrigerator magnet
*Powerful permanent magnets are made from
Ans : Alnico
* Alnico is an alloy of
Ans : Aluminium, Nickel, Cobalt and Iron
* Some organisms can detect magnetic field called
Ans : Magnetoception
* Technique using a powerful magnetic field to diagnose and treat diseases
Ans : MRI (Magnetic Resonance imaging)
* A magnet made by binding insulated copper wire over a. soft iron piece and passing an electric current through the wire is called 
Ans : Electro magnet (temporary magnet)

LAMPS

*Bulbs are usually called as
Ans : Filament lamps or Incandescent lamps
*Gases used to fill inside a filament lamp
Ans : Argon, Nitrogen
*Life-span of filament lamp
Ans : 1000 hours
*The material used for making filament of the bulb
Ans : Tungsten
*Examples of discharge lamps are
Ans : Compact fluorescent lamp, Tube lights, vapour lamps
*Life span of fluorescent lamps
Ans : 5000 hours
*A mixture of Argon and Mercury gases are filled in
Ans : Fluorescent lamps
*Phosphor - coating material used in
Ans : Fluorescent lamps
*Lamps used in advertisement boards
Ans : Neon vapour lamps
*Energy efficient in lamps means they consume
Ans : Low energy
*Electric bulb was invented by 
Ans : Thomas Alva Edison 
*Electrical oscillation was invented by:
Ans : Heinrich Hertz
*National energy conservation day 
Ans : December 14
*The electricity carrying cables buried underground made of 
Ans : Copper

VAPOUR LAMPS & COLOURS

*Argon vapour lamp - Purple
*Chlorine vapour lamp - Green
*Mercury vapour lamp - White
*Nitrogen vapour lamp - Red
*Neon vapour lamp - Orange
*Sodium vapour lamp - Yellow
*Hydrogen vapour lamp - Blue

ELECTROMAGNETIC INDUCTION

*The production of an electromotive force (voltage) across an electrical conductor due to its dynamic interaction with a magnetic field is called
Ans : Electromagnetic Induction 
*Electromagnetic induction was proposed by 
Ans : Michael Faraday
*Transformers, Microphones, Induction coil, Generators, Motors, Induction coil work on the principle of
Ans : Faraday's law of Electromagnetic Induction

MUTUALINDUCTION

*A charge of current in neighbouring coil will induce (contribute) a voltage (emf) in a coil is termed as
Ans : Mutual Induction
*The coil in which current is changed is called
Ans : Primary coil
*The coil in which the e.m.f is produced is called
Ans : Secondary coil
*Transformer, Generators works on the principle of
Ans : Mutual Induction

ENERGY CONVERSION

*Wax Candle- Chemical Energy to Heat and Light energies 
*Electric Bell- Electrical to Sound energy
*Dynamo - Mechanical to Electrical energy
*Battery - Chemical to Electrical energy
*Electric fan - Electrical to Mechanical energy
*Solar cell - Solar to Electrical energy
*Electric oven- Electrical to Heat energy
*Motor- Electrical to Mechanic energy
*Gas stove - Chemical energy to light and Heat energies
*Loud Speaker- Electrical energy to Sound energy
*Microphone - Sound energy to Electrical energy
[nww]

NUCLEAR PHYSICS

*The strongest force of nature 
Ans : Nuclear force
*Nuclear force acts between the 
Ans : Nucleons
*Father of Nuclear Physics   
Ans : Ernest Rutherford  
*Father of Nuclear Physics in India 
Ans : Homi.J.Bhabha 
*Radio activity was invented by 
Ans : Henry Becquerel
*Artificial radio activity was invented by
Ans : Irene Curie and Frederick Curie
*The process of changing nucleus of one element into other by the spontaneous emission of certain radiation 
Ans : Radio activity
*SI unit of Radioactivity
Ans : Curie
*1 becquerel = 1 decay / second 
*1 curie = 3.7 x 1010 Bq
*Radioactive substances emit 3 types of radiation
Ans : Alpha, Beta and Gama 
*The device used for detecting and measuring radiation 
Ans : Gieger counter 
*Product of Natural radioactivity 
Ans : Lead
*Particle with highest ionization energy
Ans : Alpha
*Particle with least ionization energy 
Ans : Gamma
*Particle with highest penetrating power
Ans : Alpha
*Particle with highest velocity
Ans : Gamma
*Particle with least velocity
Ans : Alpha 
*Ionisation energy
Ans : alpha>beta>gamma
*Penetrating power
Ans : gamma>beta>alpha 
*Velocity
Ans : gamma>beta>alpha 

Particle

Discovered by

Charge

Velocity

       

Equivalent

 
Alpha (a) Ernest Rutherford Positive 1       5 x 106m/s          helium nucleus
Beta (ß)         Ernest Rutherford Negative  27 x 107 m/s       electrons
Gama (y) Paul.U.Williard          No charge  3 x 108 m/s         electromagnetic waves



*Radioactive elements used as medicine
Ans : Phosphorous 32, Iodine 131, Oxygen 15
*Compound used as heavy water 
Ans : Deuterium Oxide (D2O)
*Deuterium is known as
Ans : Heavy hydrogen
*The radio active isotope used for the treatment of cancer
Ans : Cobalt 60

NUCLEAR FISSION AND NUCLEAR FUSION

NUCLEAR FUSION

*The process of combining of two lighter nuclei to give a heavier nucleus is called
Ans : Nuclear fusion
*Nuclear fusion is otherwise called as
Ans : Thermonuclear reaction
*Hydrogen bomb is based on the principle of
Ans : Nuclear fusion
*Nuclear fusion was discovered by
Ans : Hans Bathe
*Isotope of hydrogen used in nuclear fusion
Ans : Tritium
*The main source of solar energy is
Ans : Nuclear fusion

NUCLEAR FISSION

 
*The phenomenon of breaking a heavy nucleus into two light nuclei of almost equal masses along with release of huge amount of energy is called
Ans : Nuclear fission
*Uncontrolled chain reaction is the working principle of
Ans : Atom Bomb
*Nuclear fission was discovered by
Ans : Ottohann and Friz strassmann
*Enormous energy is released during atomic bomb explosion
*Time interval taken by a radioactive substance to disintegrate to half of its initial weight is called
Ans : Half life
*Radio Carbon (carbon -14) has a half life of
Ans : 5760 years
*The average lifetime of atoms in a radioactive substance is called
Ans : Mean life
*Uranium - 235 is known as
Ans : Enriched uranium
*The technique used to determine the age of fossils of animals and plants
Ans : Carbon dating
*The technique used to estimate the age of rocks from the moon
Ans : Uranium dating
*The technique used for finding the age of rocks
Ans : Rubidium - Strontium dating
*The technique used for calculating the age of caves and sea animals
Ans : Uranium - Thorium dating
*Dating method used for determining the age of archaeological materials
Ans : Thermoluminescence

NUCLEAR REACTORS 

*Fourth largest source of electricity in India 
Ans : Nuclear power 
*First atomic reactor in India
Ans : 'Apsara' in Trombay (Maharashtra)
*Chain reaction is allowed to proceed slowly and in a controlled manner in 
Ans : Nuclear reactor 
*Fuels in nuclear reactors
Ans : Uranium 233, Uranium 235, Plutonium 239
*The device used to slow down the fast moving secondary neutrons 
Ans : Moderator
*Commonly used moderators are
Ans : Heavy water, Graphite, Rods of Boron and Cadmium, Berillium oxide
*The substances used to remove the heat produced from the nuclear reactor
Ans : Coolants
*Coolant used in high temperature breeder reactor
Ans : Liquid Sodium
*The fuel used in the fast breeder reactors
Ans : Plutonium, Uranium oxide
*Neutron source is Berillium mixed with 
Ans : Polonium
*Early reactors were known as 
Ans : Atomic piles
*Atomic clock (ceasium) was discovered by 
Ans : Louis Essen

REACTORS

PURPOSE

* Power reactors Converts nuclear fission energy into electric power 
* Research reactors Produces neutrons and radio isotopes
* Production reactors Converts non-fissionable material into fissionable material

THRUST

*The total normal force exerted by a fluid on a surface is called 
Ans: Thrust
*Unit of thrust is 
Ans: Newton



WEIGHT
*The total gravitational force act on a body 
Weight 
W = mg
[m = mass of the body, 
g = acceleration due to gravity]



■

WEIGHT OF A BODY IS:

*Minimum at the Equator 
*Zero at the centre 
*Maximum at the poles of the Earth
*Weight of a body in moon is equal to
Ans : 1/ 6th of the weight of a body on earth

MASS

*The amount of matter contained in a body is called
Ans : Mass
*Mass doesn't vary with the change of its position on the earth's surface
*The device used to measure Mass of a body
Ans : Ordinary balance

DENSITY

*Density is defined as - Mass per unit of volume
Density =Mass /Volume
Relative density
=Density of body / Density of water
*Unit - Kg/m3 Density of water 
Ans : 1000kg/m3
*Density of water is maximum at - 4°C 
*Relative density is also known as
Ans : Specific gravity
*Water occupies maximum volume at - 0°C 
*When ice melts level of water remains 
Ans : Constant
*When ice melts, its volume 
Ans : Decreases

IMPULSIVE FORCE

*A very large force acting for a short period of time is called
Ans : Impulsive force
*Impulse (I) is the force that changes the 
Ans : Momentum of a body 
*I = Force x time = Ft

PASCAL'S LAW

*The law states that a force exerted on anywhere in a confined incompressible fluid is transmitted equally in all directions
Ans : Pascal's law
*Pascal's law is also known as principle of 
Ans : Transmission of fluid pressure 
*Pascal's law was discovered by 
Ans : Blaise Pascal

APPLICATIONS

*Hydraulic Jack *Hydraulic Press
*Hydraulic lifts *Flush Tank

APPLICATIONS

*Ice floats on water - Density of Ice is less than the density of water 
* A ship of iron and steel float on water - Density of iron is less than the density of water
* Iron nail sinks - Density of iron is less than the density of water
* An iron nail floats on mercury but sinks in water - Density of mercury is less than the density of iron
* Ship moves from river to sea rises little higher - Density of sea water is greater than the density of fresh water 
* It is impossible to extinguish petrol fire by water  - Density of water is greater than the density of Petrol
* Ice sinks in alcohol - Density of water is greater than density of alocohol

BUOYANT FORCE

*When a body is immersed partly or wholly in a liquid, a force acts on the body by the liquid in the upward direction. This force is called
Ans : Buoyant force 
Examples:
*A bucket of water weighs less when immersed in water

ARCHIMEDES PRINCIPLE

*When a body is completely or partly immersed in a fluid, the body experiences an upward thrust which is equal to the weight of fluid displaced by the body

FLOATATION

*The law of floatation states that a floating object displaces its own weight of the fluid in which it floats
*Weight of floating object = weight of fluid displaced

SIMPLE MACHINES

*It is a device used for performing work by applying force (effort) at a convenient point in a convenient
Ans : Direction to overcome the friction at some other point 
*It reduce human effort 
*Inclined planes.and levers are simple machines
-->effect of a simple machine
= power output / power input
*The law of lever was proposed by 
Ans: Archimedes

FULCRUM (PERMANENT POINT)

*Lever is a rigid bar capable of turning freely about a fixed point

EFFORT OR POWER (E)

*The force applied on the machine

RESISTANCE OR LOAD (R)

*The force felt by the machine 
*Mechanical advantage of a machine
= Load/Effort

LEVER

ARRANGEMENT

   

EXAMPLE

*Ist Order      RFE                 Balance, nail, puller, sea-saw, a pair of scissors
*2nd Order        ERF                Wheel barrow, nut cracker, lemon squeezer
*3rd Order         REF               Ice tongs, fishing rod, shovel etc

SCORING MACHINE

*The device used to test the purity of milk 
Ans : Lactometer
*The majority of UV radiations coming from the sun are absorbed by the 
Ans : Ozone layer
*Periscope is a device works on the principle of 
Ans : Reflection and Refraction
photometry is the branch deals with the measurement of light emitted by the 
Ans : Objects
*Father of Cybernetics
Ans : Norbert Weiner

GAS LAWS

(1)J.L.GAY - LUSSAC'SLAW

If the volume remains constant , the pressure is directly proportional to the absolute temperature
P&T
V1/T1 = V2/T2

(2)BOYLE'S LAW

IF the Pressure is Kept constant,the volume of a gas is directly proportional to its absolute temperature
V a 1/p
P1V1 = P2V2

(3)

If the pressure is kept constant,the volume of a gas is directly proportional to its absolute temperature
V a T
V1/T1 = V2/T2

(4)AVOGADRO'S LAW

Equal volume of gases at same temperature and Pressure contain equal numbers of molecules
V a n
V1/n1 = V2/n2

(5)COMBINED GAS LAW

PV = n RT
[P- Pressure,V - Volume n-number of molecules, T - Temperature, R - Constant]

TABLES

Quantity

         

Unit

               

Symbol

Mass                    Kilogram           Kg
Length                 metre                  m
Time                     second               s
Work & Energy    Joule                 J
Electric current     ampere            A
Temperature          Kelvin              K
Amount of substance mole          mol
Luminous intensity   candela       cd
Inductance                  henry            H
Intensity of 
magnetic field              Tesla            T
Momentum                 Kg metre/sec  Kgm/s
Intensity of electric
field                              Newton/coloumb    N/C
*Illuminance                   lux                        Ix
*Conductance              Siemens               S
*Capacitance                Farad                    F
*Radioactivity             Becquerel             Bq
*Resistance                    ohm                           
*Potential difference      Volt                     V
*Electric charge            Coulomb             C
*Power                              Watt                     W
*Pressure                         Pascal                Pa
*Frequency                      Hertz                   Hz
*Speed                        metre per sec         ms-1
*Volume                      cubic metre              m^3
*Area                            square metre           m^2
*Force                           Newton                       N
*Angle                            radian                       rad
*Radiant flux                   Watt                           N
*Cwlsius temperature    Degree Celsius     0C
*solid angle            steradian                       Sr
*Magnetic flux             Weber                        Wb

DIMENSIONS OF MOTION

TYPE OF MOTION

CHARACTERISTICS

                   

EXAMPLE

One dimensional motion Motion restricted to straight line     Train travelling along a straight rail
Two dimensional motion Motion restricted to a plane      Boat on a lake
Three dimensional motion Motion is space                      Gas molecules in space
*1 light year = 9.46x10^12 kilometers
*1 parsec   = 3.26 light year
*Distance between stars  = Light year
*Distance between sun and earth  = Astronomical unit
Frequency       Resulting sound wave
20Hz - 20,000Hz       Audible sound of Human 
Less than 20 Hz       Infrasonic 
Greater than 20,000Hz   Ultrasonic

DISCOVERIES

*Corpuscular theory  - Sir Isaac Newton
*Light travels faster in vacuum  - Leon Foucault
*Speed of light varies in different media  - Leon Foucault
*3 primary colours  - Thomas Young 
*Term Energy coined by  - Thomas Young
*Light is an electromagnetic wave  - Heinrich Hertz
*White light consist of different colours  - Isaac Newton
*Quantum theory  - Max Plank
*Wave theory  - Christiaan Huygens
Tachyon  - ECG Sudharshan

HEAT TRANSFER METHOD

METHOD CHARACTERISTICS            EXAMPLE
Conduction Due to vibration In solids of particles       In Solids
Convection Due to In liquid movement of and gases In Solids
                            particles
Radiation Not required any medium   Heat of sun to earth

■ C.V. RAMAN 

*Raman effect was discovered on 
Ans : Feb. 28,1928 
*February 28 
Ans : National Science Day 
*He got Nobel Prize in 
Ans : 1930
*Raman effect is associated with 
Ans : Scattering of light 
*Blue colour of sea was explained by 
Ans : CV.Raman
Different tempera ture cases    Celsius   Kelvin    Fahre nhelt
*Ice melts at          0°C                    273 K                     112 F
*Water boils at     100°C              373 K                        212 F

CONVERSION OF TEMPERATURE

*Celsius to Fahrenheit
Ans : F=(C*9/5) 32
*Fahrenheit to Celsius
Ans : C = (F - 32) *9/5
*Celsius to Kelvin Scale 
Ans : K = C  273.15  
*Kelvin to Celsius
Ans : C = K - 273.15

MICHAEL FARADAY

  
*Father of electricity
*Law of electrolysis  was put forward
*Concept of electric  field was put forward
*Invented Dynamo  
*Discovered electromagnetic induction

NUCLEAR POWER PLANTS IN INDIA

POWER PLANT          STATE

*kaiga                                     -Karnataka
*Karnataka                            -Gujarat
*Tarapur                                -Tamil Nadu
*Rawatbhat                          -Rajasthan
*Narora                                  -Uttar Pradesh



*Father of Nuclear Physics 
Ans : Ruther Ford
*Father of Indian Space Research 
Ans : Vikram Sarabhai
*Father of Indian Nuclear Programme 
Ans : Homi .J.Bhabha
*Father of Indian Atom Bomb 
Ans : Raja Ramanna 
*Father of Hydrogen Bomb 
Ans : Edward Teller 
*Father of Atom Bomb
Ans : Robert Oppenheimer 
*Father of Modern Physics 
Ans : Albert Einstein
*Lightening conductor
Ans : Benjamin Franklin 
*Bifocal lens
Ans : Benjamin Franklin 
*Astronomical telescope 
Ans : Galileo
*Human eye made up of 3 kinds of colour receptors was explained by 
Ans : Thomas Young 
*Artifical radioactivity
Ans : Irene Joliot Curie and Frederic Joliot Curie
*The term radioactivity was coined by
Ans : Madam Curie 
*The book 'Philosophiae Naturalis Principia Mathematica' was written by 
Ans : Isaac Newton
*Electromagnetic wave theory 
Ans : James Clerk Maxwell