RL PHY 1 Flashcards by Pappu Roy

●Ozone layer in the upper atmosphere is due to thereactions of: —

oxygen and ultraviolet rays

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●Radiocarbon is produced in the atmosphere as aresult of:—

collision between fast neutrons andnitrogen nuclei present in the atmosphere

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●Light year is a unit of: —

Distance

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●What will happen if the star having mass greaterthan five times of the Sun is dead? —

Black Holeswill form

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●The refractive index of the different layers of theearth’s atmosphere changes continuously,consequently the position of the image of a startchanges with time. Which of the following doesthis fact support? —

Twinkling of stars

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●Inside an aeroplane, flying at a high altitude:—

normal atmospheric pressure is maintained by theuse of air pumps

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●A vacuum cleaner works on the principle of pressuredifference. On the moon it will: —

Not work at all

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●The height of a geo-stationery satellite from theEarth’s surface is approximately: —

36,000 km

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●The technique of collecting information about anobject from a distance without making physicalcontact with it is:—

Remote Sensing

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●Suppose a rocketship is receding from the Earth at aspeed of 2/10 th the velocity of light. A light in therocketship appears blue to the passengers on theship. What colour would it appear to an observeron the Earth? —

Blue

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●Cryogenic engines find applications in:—

Rockettechnology

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●A person in a spaceship located half way between theEarth and the Sun will notice that: —

Sky is jetblack

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●A person in a spaceship located half way between theEarth and the Sun will notice that: —

Stars do nottwinkle

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●The tail of comet is directed away from the sunbecause:—

As the comet rotates around the sun,the lighter mass of the comet is pushed away dueto the centrifugal force alone

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●One astronomical unit is the average distancebetween:—

Earth and the Sun

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●The mass of a body on earth is 100 kg (accelerationdue to gravity, ge = 10 m/s2. If acceleration due togravity on the moon is ge/6, then the mass of thebody on the moon is:—

100 kg

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●Which technology is primarily used with newphysical communication medium such as satelliteand fibre optics transmission? —

Digitaltechnology

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●A geostationary satellite revolves around the earthfrom west to east in an orbit coplanar withequatorial plane at a height of about _____ abovethe surface of earth. —

36000 km

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“●In general what is range of frequency of the ““MessageSignal””?—”

Radio Frequency

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●The formation of three dimension image byinterference of two light beams from the laser orother coherent source of light is called: —

Holography

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●Diamond Ring, God’s Eye and Baily’s Beads are theparts of phenomenon? —

Solar eclipse

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●Geostationary satellite completes its one revolutionaround the earth in:—

24 hours

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●Size of the sun at dusk, Colour of the sun at dawnand Twinkle of stars in the sky are examples of: —

Optical Illusion

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●Light from the Sun reaches us in nearly: —

8 minutes

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●Stars appears to move from east to west because:—

the earth rotates from west to east

●Planets do not twinkle because:—

They are nearer toearth and hence we receive a greater amount oflight and, therefore minor variations in theintensity are not

●In the atmosphere ultraviolet rays are absorbed by:—

Oxygen

●Where are mesons found? —

Cosmic Rays

●The atmospheric layer reflecting radio waves iscalled:—

Ionosphere

●Heat from the sun reaches earth by the process of:—

Radiation

●Hydrogen spectrum was first explained by: —

NielBohr

●The source of the sun's energy is the process of:—

Nuclear Fusion

●Remote-sensing device has an inbuilt source of:—

Infrared Ray

●The atmosphere is heated mainly by:—

Radiation

●The sensation of weightlessness in a spacecraft in anorbit is due to the:—

acceleration in the orbitwhich is equal to the acceleration due to gravityoutside

●We always see the same face of the moon, because:—

It takes equal time for revolution around the earthand rotation on its own axis

●Which layer of the earth's atmosphere reflect backthe radio waves to the earth's surface? —

Ionosphere

●Sound cannot pass through: —

Vacuum

●The spoon dropped by an astronaut in a satellite will:—

continue to follow the motion of the satellite

●When a body is taken from earth to moon:—

weightchanges but mass remains same

●The instrument used to see the distant objects on theEarth is:—

Terrestrial Telescope

●The ozone hole that has been detected lies in theatmosphere above: —

Antarctica

●The sky appears blue because: —

the atmospherescatters blue colour more than the others

●The period of revolution of a geostationary satelliteis:—

24 hours

●The atmospheric air is held to the Earth by: —

Gravity

●Name the process of production of energy in the Sun:—

Nuclear Fusion

●Eclipses occur due to which optical phenomena?—

Rectilinear propagation

●In the absence of ozone layer, which rays will enterinto atmosphere? —

Ultraviolet rays

●Necessary element of change in solar energy toelectric energy is: —

Silicon

●It is dangerous to observe Solar Eclipse with nakedeyes because:—

Ultraviolet radiations from Sunburn our retina

●The minimum number of geostationary satellitesneeded for uninterrupted global coverage is: —

●The energy that can harness heat stored below theearth's surface is known as: —

Geo-thermalenergy

●A man inside an artificial satellite feels weightlessnessbecause the force of attraction due to the Earth is:—

Zero at that place

●Large astronomical telescopes always use asobjective:—

combinations of lenses

●The energy required to remove an electron in ahydrogen atom from state is: —

0.136 eV

●Who developed the technology of undergroundnuclear explosion? —

Dr. Homi Jahangir Bhabha

●In a nuclear reactor, self-sustained chain reaction ispossible, because:—

more neutrons are released ineach of the fission reactions

●Radioactivity is due to: —

Unstable nucleus

●In nuclear reactor, heavy water is used as: —

Moderator

●In a nuclear reactor, self-sustained chain reaction ispossible, because: —

the neutrons immediatelytake part in the fission process

●Curie is the unit of: —

Radioactivity

●Energy is continuously created in the sun due to:—

Nuclear Fusion

●Gamma Rays can cause: —

Gene Mutation

●Atomic power plant works on the principle of: —

Fission

●Which type of reaction produces the most harmfulradiation?—

Fission reaction

●Gamma rays have greatest similarity with: —

X Rays

●Radiocarbon dating technique is used to estimate theage of:—

Fossils

●Natural radioactivity was discovered by:—

HenriBecquerel

●Weak nuclear force causes: —

Radioactivity

●The efforts to detect the existence of Higgs bosonparticle have become frequent news in the recentpast. What is /are the importance/importance ofdiscovering this particle?—

It will enable us tounderstand as to why elementary particles havemass

●The mass of a star is two times the mass of the Sun.How it will come to an end?—

Neutron Star

●What is the minimum escape velocity of rocket to belaunched into space? —

11 Km/Sec

●Isotopes of an element contain:—

the same number ofprotons but different number of neutrons

●The difference between a nuclear reactor and anatomic bomb is that: —

the chain reaction innuclear reactor is controlled

●Nuclear sizes are expressed in a unit named:—

Fermi

●The half life of a radioactive element which has only1/32 of its original mass left after a lapse of 60days is: —

32 days

●The spectral series of the hydrogen spectrum that liesin the ultraviolet region is the: —

Lyman Series

●The mass number of a nucleus is:—

Sometimes morethan and sometimes equal to its atomic number

●The particles which can be added to the nucleus of anatom without changing its chemical properties arecalled:—

Neutrons

●A radioactive substance has a half life of 60 minutes.After 3 hours, the fraction of atom that havedecayed would be:—

12.5 %

●Hydrogen atom excites energy level fromfundamental state to n = 3. Number of spectrumlines according to Bohr, is:—

●In any Bohr orbit of the hydrogen atom, the ratio ofkinetic energy to potential energy of the electronis: — -

1/2

●Number of spectral lines in hydrogen atom is: —

Infinite

●When a hydrogen atom is raised from the groundstate to an excited state: —

Potential EnergyIncreases and Kinetic Energy Decreases

●In the spectrum of hydrogen atom, the ratio of thelongest wavelength in Lyman series to the longestwavelength in the Balmer series is: —

5/27

●The decay constant of a radioactive element is 0.01per second. Its half life period is: —

693 second

●Which model states that Mass of electron remainsconstant and Electrons in a quantized orbit willnot radiate energy?—

Bohr's Model

orbit of higher energy? —

Energy is absorbed

●The impurity atom with which pure silicon should bedoped to map a p-type semiconductor are thoseof: —

Boron

●The tendency of a liquid drop to contract and occupyminimum area is due to: —

Surface Tension

●Who gave the first experimental value of G?—

Cavendish

●A cold soft drink is kept on balance. When the cap isopened, then the weight: —

First increases andthen decreases

●A girl is swinging on a swing in sitting position. Whenthe girl stands up, the period of swing will:—

Beshorter

●A hunter aims his gun at a point between theeyebrows of a monkey, sitting on a branch of atree. Just as he fires, the monkey jumps down. Thebullet will:—

hit the monkey at the point aimed

●A man standing on a completely frictionless surfacecan propel himself by: —

Whistling

●If no external force acts on a system, its ____ cannotchange.—

Momentum

●When a simple pendulum is set into oscillation, theacceleration is ___ when the bob passes throughthe mean position.—

Zero

●In an oscillating simple pendulum, the bob attains agiven velocity _____ in each cycle. —

Twice

●In an oscillating pendulum, the amplitude of thesimple pendulum decreases with: —

Time

●An iron ball floats on mercury but gets immersed in:—

Water

●A solid cube just gets completely immersed in waterwhen a 0.2 kg mass is placed on it. If the mass isremoved, the cube is 2 cm above the water level.What is the length of each side of the cube? —

10cm

●The weight of a body decreases with the increase of:—

altitude on earth

●In an air-conditioner, heat is extracted from the roomair at the evaporator coils and is rejected out atthe:—

Condenser coils

●A 4-wheel vehicle moving in a sharp circular path athigh speed will: —

Overturn about its outerwheels

●An oil tanker is partially filled with oil and movesforward on a level road with uniform acceleration.The free surface of oil then: —

is inclined to thehorizontal with larger depth at the rear end

●The velocity of sound in air is not affected by thechange in:—

amplitude and frequency

●The velocity of sound in air increases with the ____ oftemperature. —

Increase

●If the radius of the earth were to shrink by one percent, its mass remaining the same, the value of gon the earth's surface would: —

increase by 2%

●A car is running on a road at a uniform speed of 60kmh. The net resultant force on the car is: —

equal to zero

●A spherical body moves with a uniform angularvelocity around a circular path of radius r. In thiscontext, which of the following statements is/arecorrect? —

The body has a radial accelerationdirected toward centre of path

●A weightless rubber balloon is filled with 200 cc ofwater. Its weight in water is equal to: —

Zero

●Ball bearings are used in cycles, scooters etc to: —

Reduce the friction between the wheel and theaxle

●In case of uniform circular motion, the accelerationis:—

Variable in magnitude but constant indirection

●A corked bottle full of water when frozen will breakbecause:—

The volume of water decreases onfreezing

●In an electronic watch, the component correspondingto pendulum of a pendulum clock is a: —

crystaloscillator

●It is easier to roll a stone up a sloping road than to liftit vertical upwards because: —

work done inrolling a stone is less than in lifting it

●The absorption of ink by blotting paper involves:—

capillary action phenomenon

●Siphon will fail to work if the level of the liquid in thetwo vessels are at: —

The same height

●Pa (Pascal) is the unit for: —

Pressure

●Let a thin capillary tube be replaced with anothertube of insufficient length then, we find water: —

will not rise

●If two bodies of different masses, initially at rest, areacted upon by the same force for the same time,then the both bodies acquire the same:—

Momentum

●Find the maximum velocity for the overturn of a carmoving on a circular track of radius 100 m if theco-efficient of friction between the road and tyre is0.2? —

14 m/s

●Materials for rain-proof coats and tents owe theirwater-proof properties to: —

Surface Tension

●On a clean glass plate a drop of water spreads toform a thin layer whereas a drop of mercuryremains almost spherical because: —

cohesion ofmercury is greater than its adhesion with glass

●Oil raise up the wick in a lamp. The principleinvolves:—

capillary action phenomenon

●Railway tracks are banked on curves because:—

necessary centripetal force may be obtained fromthe horizontal component of the weight of thetrain

●Mercury is commonly used as a thermometric fluidrather than water because:—

Mercury has greatervisibility than water

●On a stationary sail boat, air is blown from a fanattached to the boat. The boat: —

does not move

●ML2 T-2 is the dimensional formula for:—

coupleacting on a body

●One watt-hour is equivalent to: —

3.6 × 103 J

●One nanometer is equal to: —

10-9m

●Mica is used in electrical appliances such as electriciron because mica is: —

Electrical

●It is easier to roll a barrel full of coal tar than to pullit because:—

the rolling friction is much less thanthe sliding friction

●Minimum number of unequal vectors which can givezero resultant are: —

Three

●Rain is falling vertically downwards. To a manrunning east-wards, the rain will appear to becoming from: —

East

●An aeroplane is flying horizontally with a velocity of600 km/h and at a height of 1960 m. When it isvertically at a point A on the ground a bomb isreleased from it. The bomb strikes the ground atpoint B. The distance AB is: —

3.33 km

●If adjacent layers of material are displaced laterallyover each other, then the deformation of thematerial is called:—

Shear

●All liquids and gases stick to a solid surface so thatwhen they flow the velocity must graduallydecrease to zero as the wall of the pipe orcontainer is approached. This is called:—

Viscosity

●When the fluid particles passing successively througha given point in a fluid always follow the samepath afterwards, the flow is said to be: —

Steady

●During the flow of liquid, the slower, lower layerexerts a tangential retarding force on the upperfaster layer and experiences itself an equal andopposite tangential force. This is called:—

Tangential stress

●Viscosity is measured in: —

Pascal second

●Diamond is a polymorph of graphite. Both containcarbon atoms. Diamond is obtained afterapplying:—

Very high pressure and hightemperature

●Which element present in groundwater can bepartially removed along with removal of iron byprecipitation/coagulation method if iron is alsopresent in the water? —

Arsenic

●The known forces of nature can be divided into fourclasses, viz, gravity, electromagnetism, weaknuclear force and strong nuclear force. Withreference to them, which one of the followingstatements is correct?—

Weak nuclear forcecauses radioactivity

●When the speed of car is doubled then what will bethe braking force of the car to stop it in the samedistance?—

Four times

●The dimension of which of the following is the sameas that of impulse?—

Momentum

●If the diameter of a capillary is doubled, then the riseof water in it will be: —

Half

●Why the needle of iron swims on water surface whenit is kept gently?—

Due to surface tension

●How much calorie of energy is released by a boiledegg?—

77 calorie

●A boat will submerge when it displaces water equal toits own: —

weight

●Surface tension in a liquid is due to:—

Cohesive forcebetween molecules

●A circular plate, a cube and a sphere, all made up ofsame material and having the same mass areheated to 300 degree C and left in a room. Whichof them will have the slowest rate of cooling? —

Sphere

●Boyle's Law holds good for any gas at:

Low temperature and high pressures

●An ice block with a piece of lead embedded in it floatsin water. If ice melts, the water level: —

Falls

●The velocity of heat radiation in vacuum is:—

Equalto that of light

●The plastic material commonly used for making gearwheels is: —

Nylons

●The substance which conducts current in the solidstate is:—

Graphite

●Coolis tube is used to produce: —

X-Rays

●Which set of conditions represents the easiest way toliquefy a gas? —

Low temperature and highpressure

●What principle/law explains the working of thehydraulic brakes in automobiles? —

Pascal's Law

●Mist is caused by: —

Water vapour at lowtemperature

●While catching a ball, a player pulls down his handsto lower the: —

Momentum

●When a barometer reading suddenly recedes, itindicates that climate will be: —

Extremelystormy

●A particle dropped from the top of a tower uniformlyfalls on ground at a distance which is equal to theheight of tower. Which of the following paths willbe traversed by the particle?—

Parabolic

●When a bottle of scent is kept open in a corner of aroom its odor is felt in all parts of the room. Thisis due to the phenomenon of: —

Diffusion

●When the barometer reading dips suddenly, it is anindication of: —

Storm

●Solar energy is converted into chemical energyduring:—

Photosynthesis

●If the velocity-time graph of a particle is representedby y = mt + c, then the particle is moving with:—

Constant acceleration

●A passenger standing in a bus is thrown outwardwhen the bus takes a sudden turn. This happensdue to:—

Inertia of Motion

●When pressure is increased the melting point of ice:—

Decreases

●Plants are dried up in winter due to frost because:—

There is mechanical loss of tissues and droughtcondition prevails

●For a body moving with non-uniform velocity anduniform acceleration:

Displacement - Time graph is non-linear

●The fourth state of matter is known as: —

Plasma

●Decibel is the unit used for: —

Intensity of sound

●The term 'isoneph' indicates the lines of equal:—

Cloudiness

●The mass-energy relation is the outcome of:—

Specialtheory of relativity

●Why does bleeding occur through the nose in highmountainous regions?

The blood pressure of a person increases at highaltitudes

●Knot is a measure of: —

Speed of ship

●Boyle's law is a relationship between:—

Pressure andVolume

●Pycnometer is an instrument used to measure the:—

Density

●Who defined the law of gravitation? —

Newton

●A hydrogen balloon floats up because of:—

weight ofthe balloon is less than the weight of air displacedby it

●In a rechargeable cell what kind of energy is storedwithin the cell? —

Chemical energy

●During washing of clothes, we use indigo due to its:—

proper pigmental composition

●The energy stored in a watch spring is: —

Potentialenergy

●'Therm' is the unit of: —

Heat

●Newton's first law of motion gives the concept of:—

Inertia

●The oldest type of energy known to man is:

Geothermal energy

●Energy that is produced commercially from coal iscalled:—

Thermal energy

●Water pipes in hilly areas often burst on a cold frostynight because: —

water in the pipes freezes and onfreezing water expands, so pipes break

●A parachute descends slowly whereas a stonedropped from the same height falls rapidlybecause: —

A parachute has a larger surface areaand air resistance is more

●In a photocell light energy is converted into:—

Electrical energy

●An egg sinks in soft water but floats in a concentratedsolution of salt because:—

the density of saltsolution exceeds the density of eggs

●What should a person on a freely rotating turn tabledo to decrease his (angular) speed?—

Spread hishands outwards

●Smog is a combination of: —

Smoke and fog

●The process involved in making soap is: —

saponification

●Ventilators are provided near the ceiling of the roombecause:—

the exhaled warmer air rises up andgoes out

●The hair of shaving brush clings together whenremoved from water due to: —

Surface Tension

●The weakest of all fundamental forces is:—

Gravitational Force

●Velocity of sound in air does not change with thechange of: —

Pressure of air

●The cause for the Tsunami, as deduced by theseismologists, is:—

deformation of sea floor andvertical displacement of water

●Why is it difficult to breathe at higher altitudes?—

Due to low pressure

●The strongest force in nature is: —

Nuclear Force

●A person is hurt on kicking a stone due to: —

Reaction

●It is difficult to cook rice: —

at the top of a mountain

●What happens when two stones of different massesare dropped simultaneously from the top of abuilding?—

Both the stones reach the ground atthe same time

●Fog is an example of: —

Liquid dispersed in gas

●The modulus of rigidity is the ratio of: —

Shearingstress due to shearing strain

●Heat transfer horizontally within the atmosphere iscalled:—

Advection

●Angle of friction and angle of repose are:—

Equal toeach other

●If a boy sitting in a train, which is moving at aconstant velocity, throws a ball straight up into theair, the ball will:—

Fall into his hand

●Intensity of gravitational field of earth is maximumat:—

Poles

●The spokes used in the wheel of a bicycle increase its:—

Moment of Inertia

●A transformer works on the principle of:—

MutualInduction

●When a ship enters the sea from a river: —

It rises alittle

●Sea water can be purified by the process of: —

Distillation

●The centre of gravity of a sprinter during the racelies:—

ahead of his feet

●A piece of paper and a cricket ball are dropped fromthe same height. Under which of the followingconditions do both reach the surfacesimultaneously?—

They must be dropped invacuum

●The function of ball bearings in a wheel is:—

toconvert kinetic friction into rolling friction

●'Shock-absorbers' are usually made of steel as it:—

has higher elasticity

●The time period of a seconds pendulum is:—

2seconds

●Amount of water vapour in the atmosphere ismeasured in terms of: —

Humidity

●A spherical ball made of steel when dropped inmercury container will:—

will be on the surface ofmercury

●Vehicle tyres are inflated properly:—

to avoidskidding and to minimise friction

●Should cars have bumpers that collapse underimpact?—

Yes, since they help to absorb theimpact of a collision and keep the occupants safe

●Ice cubes are added to a glass of pure water and aglass of pure alcohol. The ice would:—

float inalcohol and sink in water

●What is the principle of a life jacket?

It increases the volume of the person to keep him afloat

●A rubber ball is dropped from a height of 2 metres.To what height will it rise, if there is no loss ofenergy/velocity after rebounding?—

2 metres

●When a pail of water is swung in a vertical circle, thewater does not fall out at the top of the loop whenthe speed is:—

Above a certain minimum valueirrespective of amount of water in the pail

●Who enunciated the laws of planetary motion?—

Johannes Kepler

●The radiant energy having lowest energy is:—

Microwave radiation

●Damp clothes are dried in spin dryers by the actionof:—

centrifugal forces

●An aircraft can perform aerobatic manoeuvres in avertical loop because of: —

Gravity

●Sprayer functions on: —

Bernoulli's Principle

●The wall of a dam is broader at the base:—

towithstand pressure that increases with depth

●Which conservation principle is applicable in the caseof the motion of a rocket? —

Conservation ofmomentum

●It is easier to carry two buckets of water in one handeach, than to carry only one in one hand because:—

Centre of gravity and centre of equilibrium fallwithin the feet

●The surface tension of water on adding detergent toit:—

decreases

●In a refrigerator, the cooling system should alwaysbe:—

at the bottom

●The radiation initially produced in fluorescent tubeis:—

Ultraviolet

●The 'four stroke petrol engine' is based on: —

Otto-cycle

●In an ordinary glass tube and a glass capillary tubeare both dipped in a beaker of water, water risesin:—

both

●Small bubbles are perfectly spherical because of:—

Surface tension

●Two rods, one of copper and other of steel, experiencethe same upthrust when placed in water. Thus,both have:—

Equal volume

●A single fixed pulley is used to draw water from awell because: —

Force is applied in a convenientdirection

●The audio signals of TV are: —

Frequency modulated

●In mirrors, the back surface is coated with a thinlayer of:—

Silver

●A bomb at rest explodes into a large number of tinyfragments. The total momentum of all thefragments:—

is zero

●The slope of velocity-time graph represents:—

Acceleration

●A bullet is fired from a rifle which recoils after firing.The ratio of kinetic energy of the rifle to that ofthe bullet is: —

Zero

●What happens to a liquid, when the vapour pressureequals the atmospheric pressure? —

The liquidboils

●Tear gas used by the police to disperse the mobcontains:—

Chlorine

●Why do birds not have respiratory trouble at the timeof flying at high altitude? —

They have extra airsacs

●Conversion of heat into electrical form s achieved byusing:—

Thermocouple

●When milk is churned, the separation of cream fromit takes place by the process of:—

centrifugal force

●A bottle of soda lime is grasped by the neck andswung briskly in a vertical circle. Near whichportion of the bottle do the bubbles collect? —

Near the neck

●Water from soil enters into the root hairs owing to:—

Capillary pressure

●As we go from Equator to North Pole, the value of'g', the acceleration due to gravity: —

increases

●Fat can be separated from milk in a cream separatorbecause of: —

Centrifugal force

●In the Earth, the weight of body is maximum at the:—

Surface

●Direct conversion of solar energy with the use of aphoto-voltaic cell results in the production of: —

Electrical energy

●If we want to calculate the pressure of a liquid at thebottom of a vessel, the quantity which is notrequired to determine it, is: —

Surface area of thebottom of the vessel

●A stone is dropped from the roof of a house towardsthe ground. The kinetic energy of the stone will bemaximum:—

Just before it touches the ground

A black body can absorb radiations of: —

allwavelengths

●If we want to calculate the pressure of a liquid at thebottom of a vessel, the quantity which is notrequired to determine it, is: —

Surface area of thebottom of the vessel

●Optical fibres works on the principle of:—

TotalInternal Reflection

●An air bubble in water will act like a: —

Concavelens

●For given incident ray, if a plane mirror is rotatedthrough a certain angle, then the ____ ray rotatesthrough twice of that angle. —

Reflected ray

●Total Internal Reflection can take place when lighttravels from: —

Diamond to glass

●An ordinary light bulb has a rather short life becausethe:—

Bulb cannot be evacuated completely

●An ordinary light bulb has a rather short life becausethe:

Wires supporting the filament melt at a hightemperature

●If a person looks at a coin which is in a bucket ofwater:—

the coin will appear to be closer thanreally is

●An image formed on the retina of an eye persists forabout ____ after the removal of stimulus. —

0.1seconds

●Light is totally reflected when the angle of incidenceexceeds a certain critical value and:

light travelling in a denser medium is reflected froma rarer medium

●When a CD (compact disc used in audio and videosystems) is seen in sunlight, rainbow like coloursare seen. Thos can be explained on the basis of thephenomenon of:—

Refraction, diffraction andtransmission

●When light waves pass from air to glass, the variablesaffected are: —

Wavelength and velocity

●Due to terrestrial heating and ____ of light themirage forms in desert. —

Refraction

●Diffusion of light in the atmosphere takes place dueto:—

Dust particles

●The splitting of different colours of light in a prism is:—

Dispersion of Light

●Optical fibre works on the principle of:—

TotalInternal Reflection

●The colour of an opaque object is due to the colour it:—

reflects

●The information of brilliant colours in a thin soapfilm is a consequence of the phenomena of: —

Multiple reflection and interference

●The basic reason for the extraordinary sparkle ofsuitably cut diamond is that: —

it has a very highrefractive index

●The speed of light will be minimum while passingthrough:—

Glass

●An air bubble in water will act like a: —

concave lens

●Mirage is due to:—

unequal heating of different partsof the atmosphere

RL PHY 1 Flashcards

(286 cards)