RL PHY 2 Flashcards
●Lux is the SI unit of: —
intensity of illumination
●On a rainy day, small oil films on water show brilliantcolours. This is due to: —
Interference
●Light travels at the fastest speed in: —
Vacuum
●Light Emitting Diodes (LED) is used in fancyelectronic devices such as toys emit: —
Visiblelight
●Rainbow is produced when sunlight fall on drops ofrain. Which of the following physical phenomenaare responsible for this? —
Refraction andInternal Reflection
●All the rays coming from the source at the focus of aparabolic mirror are reflected as an intense:—
Parallel beam
●Advanced sunrise and delayed sun- set found in thesky are due to the phenomenon of: —
Refractionof sunlight
●Recording a permanent three dimensionalphotograph of a given single colour or a multi-colour is known as:—
Holography
●What is colour of light related to: —
Frequency
●What is viewed through an electron microscope?—
Structure of bacteria and virus
The instrument which uses sound waves to measurethe depth of oceans is: —
SONAR
●Which combination of colour is the most convenientduring day and night time? —
Red and Green
●The speed of light with the rise in the temperature ofthe medium: —
Remains unaltered
●What is the wavelength of visible spectrum? —
3900Angstrom-7600 Angstrom
●Who measured the velocity of light first? —
Romer
●An electron microscope gives higher magnificationthan an optical microscope because:—
thewavelength of electrons is smaller as compared tothe wavelength of visible light
●Lamberts law is related to: —
Illumination
●Danger signals are generally red as red light:—
Undergoes least deviation
●A simple microscope consists of:—
A short focusconvex lens
“●”“Short-sight”” in human eye can be corrected by usingproper:—”
Concave lens
●What is the reason for twinkling of stars?—
Atmospheric refraction
●Which colour is the complementary colour of yellow?—
Blue
●A pond of water appears less deep due to: —
Refraction
●The reason for a swimming pool to appear less deepthan the actual depth is: —
Refraction
●The type of mirrors used in the headlamp of cars is:—
Parabolic Concave
●When a person walking in bright Sunlight enters adark room, he is not able to see clearly for a littlewhile because:—
The iris is unable to dilate thepupil immediately
●Spectacles used for viewing 3D films have: —
Polaroid
●According to the theory of relativity, which of thefollowing always remains constant?—
Velocity ofLight
●A colour-blind person cannot:—
distinguish betweencertain colours
●A photo-electric cell converts: —
Light energy toelectrical energy
●A concave lens always forms an image which is:—
Virtual and erect
●Lens is made up of: —
Flint Glass
●One can distinguish a telescope from a microscope byobserving: —
Length and size of the lens
●For a person having hypermetropia, the near point is:—
greater than 25 cm
●Light houses are places with powerful lights to: —
guide and warn the ships coming from differentdirections in the ocean
●Persistence of vision is the principle behind: —
Cinema
●The light rays used for eliminating bacteria are:—
ultraviolet radiation
●A person wears spectacles with concave lenses. Itmeans that normally (when not using glasses), theimage of distant objects is focussed in his eyes: —
in front of the retina
●Myopia is the same as: —
Near sightedness
●A microscope used in pathological laboratoriesforms:—
Magnified, virtual and inverted image
●The magnifying power of an astronomical telescopecan be decreased by:—
Increasing the focal lengthof the eyepiece
●The owl can see most clearly in the dark because:—
ithas large eyes with orbs directed forward, givingit binocular sight
●Night photography and photography in mist and fogare possible using: —
Infra-red radiation
●The blue colour of water in the sea is due to:—
absorption of other colours except blue by watermolecules
●Rainbow is seen after rain because of hangingmolecules of water which act as: —
Prisms
●In sunlight, a rose appears red. In green light, thesame rose appears: —
Black
●The sparkling of a diamond is due to:—
TotalInternal Reflection of light
●Parabolic mirrors are used in: —
Car headlights
●The sharpness of a television image is termed as its:—
Resolution
●The final image in a simple microscope is:—
Virtual,magnified and erect
●Hypermetropia or long sight can be corrected byusing:—
Convex lenses
●An optically plane surface reflects a beam of light:—
as diffused beams in all directions
●A periscope works on the principle of:—
Totalinternal reflection
●A rear-view mirror for driving is: —
Convex
●The part of the eye having the largest refractive indexis:—
Lens
●A man cannot see clearly beyond 10 metres. Thedisease he suffers from is: —
Myopia
●Energy in reflected light:—
increases with increase inangle
●Which colour of light shows maximum deviationwhen passed through a prism? —
Violet
●When a light wave is reflected from a mirror, there isa change in its: —
Amplitude
●Which type of mirror is used in the head lights ofvehicles?—
Concave mirror
●Shaving mirror is: —
Concave
●Magnifying glass is basically a: —
Convex lens
●White clothes are cooler than black ones becausethey:—
reflect all the light that reaches them
●The primary colours in photography are:—
Red,Blue, Yellow
●A concave lens always forms: —
a virtual image
●A water tank appears shallow when it is viewed fromtop due to:—
refraction
●For a ray of light to suffer total internal reflection, ithas to pass from: —
air to water
●When air rises, it is cooled by: —
Expansion
●Collision of metal atoms with each other releases:—
Heat energy
●The temperature of a metal wire ____ ,when anelectric current is passed through it. —
Rises
●Low temperatures (cryogenics) find application in:—
Space travel, surgery and magnetic levitation
●A stick is dipped in water in a slanting position. Ifobserved sideways, the stick appears:—
Short andbent at the surface of water.
●A piece of copper and a piece of glass are heated tothe same temperature. When touched, thereafter,:—
the copper piece appears hotter than the glasspiece.
●The boiling point of ____ decreases as the amplitudeincreases. —
Water
●When water is heated from 0 degree celsius to 10degree celsius, its volume:—
first increases andthen decreases
●A hollow sphere of radius R, a hollow cube of side Rand a thin circular plate of radius R, made up ofthe same material, are all heated to 200 C aboveroom temperature. When left to cool in the room,which of them will reach the room temperaturefirst? —
Sphere
●With the increase of temperature, the viscosity ofglycerine:—
Increases
●On a cold day when a room temperature is 150 C, themetallic cap of a pen becomes much colder thanits plastic body, though both are at the sametemperature of 150 C, because:—
metals are goodconductor of heat
●When a ring of metal is heated what happens to itshole?—
It expands
●When heated from 0 degree to 10 degree celsius, thevolume of a given mass of water will:—
Decreaseand then will increase
●The best conductor of heat among the following is:—
Mercury
●Clear nights are colder than cloudy nights because of:—
Radiation
●A gas thermometer is more sensitive than a liquidthermometer because a gas: —
Is easy to obtain
●The metal used for the manufacture of heatingelements provided in electric iron is —
Nichrome
●’Cryogenics’ is a science dealing with: —
Lowtemperatures
●If the temperature of a place increases suddenly, therelative humidity: —
Decreases
●Why two thin shirts can keep us warmer than a singlethick shirt in winter?—
Air layer between twoshirts behaves like insulating media
●What changes will happen to a bowl of ice and waterkept at exactly zero degree celsius? —
No changewill happen
●Curie point is the temperature at which:—
A metalloses magnetic properties
●Cloudy nights are warmer compared nights becauseclouds mainly:—
reflect back the heat given byearth
●A metal plate with a circular hole at the centre isheated. What will happen to the area of the hole?—
Increase
●Lakes freeze in cold countries in winter, leaving thewater underneath at: —
4 degree celsius
●Refrigeration is a process which:—
slows down thebacterial growth
●Air coolers are more suitable for: —
hot and dryclimate
●When hot-water is sprinkled on a hotter glasstumbler, it breaks because: —
glass suddenlycontracts
●If there is a circular hole in a metal plate, whathappens to the radius of the hole when the plate isheated?—
It increases
●Mud houses are cooler in summers and warmer inwinters as compared to brick houses because:—
Mud is a bad conductor
●In heating frozen foods in sealed pouches inmicrowaves, why do you first poke holes in thepouch? —
To prevent the steam pressures frombursting open the pouch
●Steam at 1000 Celsius causes more severe burns thanwater at 1000 Celsius because:—
Steam has latentheat of vaporization
●During the hot weather, the fan produces a feeling ofcomfort. This is because: —
our perspirationevaporates rapidly
●In a diesel engine, the high temperature needed toignite the fuel is achieved by: —
compressing airin the cylinders
●How much mechanical work must be done tocompletely melt 1 gram of ice at 00 celsius? —
80J
●Heat stored in water vapour is: —
Latent Heat
●A copper disc has a hole. If the disc is heated, the sizeof the hole: —
increases
●Water boils at a lower temperature in the hillsbecause: —
there is a decrease in air pressure onthe hills
●The temperature which has the same reading on bothFahrenheit and Celsius scales, is: —
Minus 40degree celsius
●A body absorbs heat most if it is: —
black and rough
●The temperature of boiling water in a steam enginemay be high because of: —
there is high pressureinside the boiler
●The water from a hand pump is warm in winterbecause:—
The temperature inside the earth ishigher than the atmospheric temperature
●Water is used in hot water bags because:—
It hashigh specific heat
●Which device is used in D.C. circuits?—
Transformer
●Domestic electrical wiring is basically a:—
parallelconnection
●At the present level of technology available in India,solar energy can be conveniently used to: —
Supply hot water to residential buildings
●A fuse is used in mains electric supply as a safetydevice. Which one of the following statementsabout the fuse is correct?—
It must have a lowmelting point
●In a motor car battery, the voltage is usually: —
12 V
●Fluorescent tubes are fitted with a choke. The chokecoil:—
Reduces current in the circuit
●Two wires have their lengths, diameters andresistivity all in the ratio of 1:2. If the resistance ofthe thinner wire is 10 ohm, the resistance of thethicker wire is: —
10 ohm
●The frequency of alternating voltage supplied is: —
50 Hz
●What is the order of magnitude of electric resistanceof the human body (dry)? —
106 ohm
●Basically domestic electric wiring is a:—
combinationof series and parallel connections
Large transformers, when used for some time, becomevery hot and are cooled by circulating oil. Theheating of the transformer is due to: —
both theheating effect of current and hysteresis loss
●Metals are good conductors of electricity because:—
They contain free electrons
●Rectifiers are used to convert: —
Alternating currentto Direct current
●Point A is at a lower electrical potential than point B.An electron between them on the line joining themwill:—
Move towards B
●Suitable impurities are added to a semiconductordepending on its use. This is done in order to:—
increase its electrical conductivity
●Substances which offer no resistance to the flow ofelectricity are known as: —
Superconductors
●In which of the following industries is mica used as araw material? —
Electrical
●One should not connect a number of electricalappliances to the same power socket because:—
this can damage the domestic wiring due tooverloading
●Transformer is used to:—
Convert low A.C voltage tohigh voltage
●Electrical energy can be easily and cheaply changedfrom one voltage to another by a ____ withoutmuch loss of energy.—
Transformer
●The filament of electric bulb is generally made oftungsten because: —
melting point of tungsten ishigh
●Which term is used to denote materials with a muchhigher conductivity than insulators but a muchlower conductivity than metals? —
Semiconductor
●In electronics what comes under tank circuit?—
Capacity and inductance
●The fundamental scientific principle in the operationof battery is: —
Dissociation of electrolytes
●Good conductor of electricity is: —
Graphite
●Electrostatic precipitator is used to control thepollution of:—
Thermal
●When the main switch of the house is put off itdisconnects the: —
live wire and the neutral wire
●A multimeter is used to measure:—
Current, Voltage,resistance
●A device used for converting Alternating Currentinto Direct Current is called: —
Rectifier
●The metal used to make lightning conductors is: —
Copper
●Superconductors are those elements:—
whoseresistance falls almost to zero at very lowtemperatures
●Alternating current is converted into direct currentby:—
Rectifier
●Which of the following circuit elements is used to’block’ DC in an electronic circuit? —
Capacitance
●The fuse in our domestic electric circuit melts whenthere is a high rise in: —
Current
●The device used to change the speed of an electric fanis:—
Regulator
●Pure water is bad conductor of electricity because itis:—
feebly ionized
●When electricity is transmitted over long distances:—
There is less wastage of energy
●Electric current in a metal wire is due to the flow of:—
Electrons
●After long periods of use, a grey spot develops on theinside of a bulb. This is because: —
The tungstenfilament evaporates and collects there
●Lightening is caused due to: —
electric discharge
●The device which transfer the signal from lowresistance region to high resistance region is: —
Transistor
●A bird sitting on a high tension electric wire does notget electrocuted because:—
it does not form aclosed path for the flow of current
●If a copper wire is increased to double its length, itsresistance will become: —
Double
●Superconductor is the conductor whose ___ is zero.—
Resistance
●A device which is used to limit the current in anelectrical circuit is called: —
Fuse
●The earth wire of a cable is connected to:—
the fuseof the appliance
●Water cannot be used to extinguish fire caused byelectric current, because:—
it may causeelectrocution
●The metal whose electrical conductivity is more, is:—
Silver
●Moving electric charge produces: —
Magnetic field
●The S.I. unit of electric charge is: —
Coulomb
●The best material for the core of a transformer is:—
Soft iron
●Metal tea pots have wooden handles because:—
itprevents electric shock
●The best conductor of electricity among the folloiwngis :—
Silver
●Electromagnetic theory was proposed by: —
Maxwell
●Magnetism at the centre of a bar magnet is: —
Zero
●When a vehicle passes TV reception gets distorted.This is because:—
Spark plug creates
●Magnetism in materials is due to:—
Circular motionof electrons
●In the process of magnetization of a bar:—
The entirebulk of the bar gets magnetized
●The scientist who first sent electromagnetic waves todistant places is: —
Thomas Alva Edison
●When a bar magnet is cut into two equal halves, thepole strength of each piece: —
Remains the same
●In MRJ machine, which one of the following is used?—
Magnetic Wave
●Tape Recorder should not be kept near which one ofthe following things? —
Magnet
●The width of depletion layer of a P-N junction:—
isincreased under reverse bias
●Modern movie songs released are the best in qualityof sound. The rich quality of sound is due to whichone of the following?—
Consists of manyharmonics
●When the frequency distribution is normal:—
Mean,mode, and median are identical
●For reproducing sound, a CD (Compact Disc) audioplayer uses a: —
Laser Beam
●Which waves are produced by rapidly oscillatingelectrical current?—
Radio waves
●To detect the over-speeding vehicles, police use theDoppler effect of reflected: —
Short radio waves
●What is the term for the form of amplitude variationsin the transmitted signal due to atmosphere,industries etc?—
Noise
●Which transmission of music is a very good qualitymusic because the atmospheric or man madenoises which are generally frequency variationscan do little harm?—
FM Transmission
●Sound waves in air are: —
Longitudinal
●RADAR is used for: —
detecting and locating theposition of objects such as aeroplanes
●Sound of frequency below 20 Hz is called: —
Infrasonic
●The melodious effect on our ear produces by thecombination of two or more notes of the modernpop songs is called:—
Concord
●Sound travels with a different speed in media. Inwhat order does the velocity of sound increase inthese media?—
Air, Water and Iron
●Sound travels at the fastest speed in: —
Steel
●Sound produced at a point is heard by a person after5 second, while the same sound is heard byanother person after 6 seconds. If the speed ofsound is 300 m/s, what could be the maximum andminimum distances between the two persons?—
3.3 km, 0.30 km
●Intensity of sound at a point is ____ its distance fromthe source. —
Inversely proportional to the squareof
●Supersonic plane fly with the speed:—
greater thanthe speed of sound
●Mach number is used in connection with the speed of:—
aircraft
●Intensity of sound has an: —
Object existence
●What is found in frequency modulation?—
Fixedfrequency
●Two waves each of amplitude 1.5 mm and frequency10 Hz are travelling in opposite direction with a speed of 20 mm/s. Thedistance in mm between adjacent nodes is: —
1.0
●A person standing on a railway platform listens to thewhistles of arriving and departing trains. Thewhistle heard is:—
of higher pitch when trainarrives
●Why are we able to hear short wave broadcasts in abetter way than long wave broadcasts?—
Shortwaves are more energetic than long waves
●Longitudinal waves cannot travel through: —
Vacuum
●Submerged objects can be located using: —
SONAR
●A decibel is: —
A measure of sound level
●In a Laser (say neon laser) all the atoms emit the lightwaves of:—
Same frequency, same amplitude andsame phase
●What is the full form of ‘AM’ regarding radiobroadcasting?—
Amplitude Modulation
●The propagation of sound waves in a gas involves: —
Adiabatic compression and rarefaction
●If input frequency of a full wave rectifier be n, thenoutput frequency would be: —
2n
●Noise is measured in: —
Decibel
●The bats can fly in the dark because:—
they generateultrasonic sound waves
●The frequency of ultrasound wave is typically:—
Below 20 kHz
●The sound produced by a bat is: —
Ultrasonic
●The sounds having a frequency of 20 Hertz to 20,000Hertz are known as: —
Audible sounds
●When a vibrating tuning fork is placed on a table, aloud sound is heard. This is due to: —
Forcedvibrations
●The distance between node and adjacent anti-node is30 cm, the wavelength is: —
60 cm
●The velocity of sound in air:—
decreases withdecrease of temperature
●The audio signals of TV are: —
Frequency modulated
●To measure the speed of an approaching car, a policeofficer shines: —
radio waves on it
●Waves that are required for long distance wirelesscommunication are: —
Radio waves
●These waves cannot be transmitted through vacuum:—
Sound
●Speed of sound in air is unaffected by change in:—
Pressure
●Negative feedback in amplifiers:—
increasesbandwidth and decrease noise
●Permissible noise level at Residential area duringnight time is:—
45 dB (A)
●The pitch of sound depends on its:—
Frequency
●The technique used to transmit audio signals intelevision broadcasts: —
Frequency Modulation
●When the same note is played on a sitar and a flute,the sound produced can be distinguished fromeach other because of the difference in: —
Qualityonly
●The distance between two consecutive crests in awave train produced in a string is 5 cm. If 2complete waves pass through any point persecond, the velocity of the wave is:—
10 cm/sec
●The speed of a wave in a medium is 760 m/s. If 3600waves are passing through a point, in the mediumin 2 minutes, then its wavelength is: —
25.3 m
●The number of waves contained in unit length of themedium is called: —
Wave Number
●The frequency of a sound wave is n and its velocity isv. If the frequency is increased to 4n the velocity ofthe wave will be:—
v
●When sound waves travel from air to water, which ofthe following remains constant? —
Frequency
●Sound waves have the following frequencies that areaudible to human beings: —
5000 c/s
●It is possible to distinguish between the transverseand longitudinal waves by studying the propertyof: —
Polarization
●A pulse or a wave train travels along a stretchedstring and reaches the fixed end of the string. Itwill be reflected back with: —
A phase change of180° with velocity reversed
●A medium can carry a longitudinal wave because ithas the property of: —
Elasticity
●The waves in which the particles of the mediumvibrate in a direction perpendicular to thedirection of wave motion is known as: —
Transverse Wave
●The type of waves that can be propagated throughsolid is:—
Transverse and Longitudinal
●A tuning fork produces waves in a medium. If thetemperature of the medium changes, then whichof the following will change? —
Wavelength
●A travelling wave passes a point of observation. Atthis point, the time interval between successivecrests is 0.2 seconds and the frequency is: —
5 Hz
●Which one among the following lasers is used incancer treatment? —
CO2 laser
●A simple machine helps a person in doing:—
thesame amount of work with lesser force
●The working principle of a washing a machine is:—
Centrifugation
●The working principle of a washing machine is:—
Centrifugation
●Cryogenic engines find application in: —
RocketTechnology
●The working of the quartz crystal in the watch isbased on the:—
Piezo-Electric Effect
●The instrument that measures and records therelative humidity of air is: —
Hygrometer
●Instrument used to measure the force and velocity ofthe wind is: —
Anemometer
●Which of the following is used for accuratelymeasuring very small time intervals? —
Atomicclocks
●The instrument for measuring intensity ofearthquakes is called: —
Seismograph
●The instrument used to measure the speed of thewind is:—
Anemometer
●Bolometer is used to measure: —
Temperature
●A new technology which provides the ability to createan artificial world and have people interact with itis called:—
Virtual Reality
●The material used in the fabrication of a transistor is:—
Silicon
●The device which converts sound energy intoelectrical energy is called: —
Microphone
●A Photostat machine works on: —
electrostatic imagemaking
●Forged documents are detected by:—
Ultra-violetrays
●The important unit of a microprocessor is:—
ALU,array of registers and control unit
●Flight Recorder is technically called: —
Black Box
●An instrument is used to measure humidity is:—
Hygrometer
●An instrument that records earthquakes is:—
Seismograph
●Electrostatic precipitator is used to control:—
Airpollutants
●Velocity of sound in air does not depend on:—
Pressure of air
●Glass can be etched or scratched by:—
Diamond andHydrofluoric Acid
●What is fast becoming a very important field ofactivity in India? —
Information technology
●The correctly matched lists are: — High Speed:Mach; Wavelength:
Angstrom; Pressure: Pascal;and Energy: Joule
●What is the term for a plastic card with an embeddedmicrochip? —
Smart Card
