1) Earth is also known as –
Answer
Blue planet
2) The energy that can harness heat stored below the earth's surface is known as –
Answer
geothermal energy
3) Green house effect is the heating up of the Earth's atmosphere which is due to –
Answer
the infra-red rays
4) If the phase difference between two points is 120° for a wave with velocity of 360 m/ and frequency 500 Hz, then path difference between the two points is –
Answer
24 cm
5) The colour of sky appears blue due to –
Answer
scattering of shorter wave lengths
6) Materials for rain proof coats and tents owe their water proof properties to –
Answer
Surface tension
7) If no external force acts on a system of bodies, the total linear momentum of the system of bodies remains constant. Which law states this?
Answer
Principle of conservation of linear momentum
8) A particle is moving in a uniform circular motion with constant speed v along a circle of radius r. The acceleration-of the particle is -
Answer
V²/r
9) What was invented by 'Zacharias Janssen'?
Answer
Microscope
10) The unit of measurement of noise is –
Answer
Decibel
11) Period of oscillation of 3 cm microwaves in seconds is –
Answer
1 x 10⁻¹⁰
12) For which Diode is used?
Answer
purificationin
13) The force which opposes the relative motion between different layers of liquid or gases is called -
Answer
Viscous Force
14) Water has maximum density at .
Answer
4 C
15) Sensitivity of the human eye is maximum in the –
Answer
Green region
16) The speed of light in air is –
Answer
3 x 10⁸ m/s
17) The speed of light with the rise in the temperature of the medium :
Answer
Remains unaltered
18) A rocket works on the principle of conservation of .
Answer
linear momentum
19) The swing of a spinning cricket ball in air can be explained on the basis of –
Answer
Turbulence caused by wind.
20) Which layer of the earth’s atmosphere reflects back the radio waves to the earth’s surface?
Answer
Ionosphere
21) What is the process of melting also called?
Answer
Fusion
22) A man inside an artificial satellite feels weightlessness because the force of attraction due to earth is –
Answer
zero at that place
23) 'Shock-absorbers are usually made of steel as it –
Answer
has higher elasticity
24) What is the maximum value of deforming force upto which a material shows elastic property and above which the material loses it?
Answer
Elastic Limit
25) With the increase of pressure, the boiling point of any substance -
Answer
Increases
26) Velocity of the sound is minimum in -
Answer
Vacuum
27) Safety fuse wire used in domestic electrical appliances is made of metal of low –
Answer
Melting point
28) A bottle of sodalime is grasped by the neck and swung briskly in a vertical circle, Near which portion of the bottle do the bubbles collect?
Answer
Near the neck
29) Lambert's law is related to –
Answer
Illumination
30) When a detergent is added to pure water, its surface tension –
Answer
decreases
31) Small bubbles are perfectly spherical because of –
Answer
Surface tension
32) The final image in a simple microscope is –
Answer
virtual, magnified and erect
33) A single fixed pulley is used to draw water from a well because –
Answer
force is applied in a convenient direction
34) Hyperrnetropia or longsight can be corrected by using :
Answer
Convex lenses
35) Stars appear twinkling because of of light.
Answer
Scattering
36) In mirrors the back surface is coated with a thin layer of :
Answer
Silver
37) A bomb at rest explodes into a large number of tiny fragments. The total momentum of all the fragments –
Answer
is zero
38) Sound energy passing per second through a unit area held perpendicular is called -
Answer
Intensity
39) Speed of sound in air is unaffected by change in :
Answer
Pressure
40) The audio signals of TV are :
Answer
Frequency modulated
41) A light year is a measure of :
Answer
Distance
42) A device which is used to limit the current in an electrical circuit is called a -
Answer
Fuse
43) Two rods, one of copper and other of steel, experience the same up thrust when placed in water. Thus, both have –
Answer
equal volume
44) Minimum numbers of unequal vectors which can give zero resultant are -
Answer
three
45) Water is not suitable as a calorimetric substance because it –
Answer
has high specific heat
46) When a body falls from an aeroplane, there is increase in its –
Answer
Acceleration
47) Energy is continuously created in the sun due to –
Answer
nuclear fusion
48) When the barometer reading dips suddenly, it is an indication of –
Answer
Storm
49) Good conductor of electricity is –
Answer
graphite
50) The fourth state of matter is known as –
Answer
Plasma
51) Radio waves, microwaves, infra-red spectrum, ultraviolet rays, X-rays and gamma rays are classified as _.
Answer
electromagnetic waves
52) A falling drop of rain water acquires the spherical shape due to –
Answer
Surface Tension
53) This scientist gave the law- ‘Properties of elements are a periodic function of their atomic number.’ This property of the fundamental importance of atomic number was discovered by-
Answer
Henry Moseley
54) The mass and energy equivalent to 1 a.m.u. respectively are -
Answer
1.67 x 10−27kg, 931.5 MeV
55) A spherical ball made of steel when dropped in mercury container will –
Answer
will be on the surface of mercury
56) The sounds having a frequency of 20 Hertz to 20,000 Hertz are known as –
Answer
Audible sounds
57) Gamma rays have greatest similarity with –
Answer
X-rays
58) In the absence of ozone layer, Which rays will enter into atmosphere?
Answer
Ultraviolet
59) Light year is the unit of -
Answer
Distance
60) An object at rest will remain at rest and an object in motion will remain in motion until and unless it is acted upon by an external force. This is Newton's -
Answer
First law
61) Cathode rays when obstructed by metal cause emission of -
Answer
X – ray
62) Sensation of sound persists in our brain for about -
Answer
0.1s
63) Which physical quantity is measured in ‘siemens’?
Answer
Electrical conductance
64) The surface tension of water on adding detergent to it –
Answer
decreases
65) In a refrigerator, the cooling system should always be –
Answer
at the bottom
66) The base of an electric iron is brightly polished mainly -
Answer
to reduce heat loss by radiation
67) If the length of a simple pendulum is halved then its period of oscillation is -
Answer
decreased by a factor √ 2
68) Lux is the SI unit of -
Answer
intensity of illumination
69) Eclipses occur due to which optical phenomena?
Answer
Rectilinear propagation
70) Pure water is bad conductor of electricity because it is –
Answer
feebly ionized
71) Pycnometer is an instrument used to measure the –
Answer
Density
72) Lamberts law is related to –
Answer
Illumination
73) Rain drops acquire spherical shape due to -
Answer
surface tension
74) The angular velocity depends upon the rate of change of the .
Answer
Angular Displacement
75) Coolis tube is used to produce –
Answer
X-rays
76) What is found in frequency modulation?
Answer
Fixed frequency
77) When the speed of car is doubled, then what will be the braking force of the car to stop it in the same distance?
Answer
four times
78) What is the maximum value of deforming force up to which a material shows elastic property and above which the material loses it?
Answer
Stress
79) The method of protecting iron from rusting, by coating a thin layer of Zinc is called -
Answer
Galvanizing
80) Ultra violet radiations of the Sun do not reach the earth because, earth's atmosphere is surrounded by –
Answer
Ozone
81) "Curie" is unit of :
Answer
Radioactivity
82) Speed of sound is the greatest in :
Answer
Glass
83) Laser is a device to produce -
Answer
coherent light
84) The hydraulic brakes used in automobiles is a direct application of :
Answer
Pascal's law
85) A kilowatt-hour is unit of –
Answer
Energy
86) Nuclear reactors used to produce electricity are based on –
Answer
Nuclear fission
87) Energy that is produced commercially from coal is called –
Answer
Thermal energy
88) The source of the Sun's energy is the process of –
Answer
Nuclear fusion
89) A boy sitting in a train moving with a uniform velocity drops a coin outside. A man standing outside the train will find the trajectory of the coin to be -
Answer
a parabola
90) Solar energy is converted into chemical energy during –
Answer
Photosynthesis
91) Decibel is the unit used for –
Answer
Intensity of sound
92) The term ‘Isoneph' indicates the lines of equal –
Answer
cloudiness
93) Fibre optics work on the principle of –
Answer
Total internal reflection
94) A decibel is –
Answer
A measure of sound level
95) The type of mirrors used in the headlamps of cars is –
Answer
Parabolic concave
96) If lift is going up with acceleration, the apparent weight of a body is -
Answer
more than the true weight
97) The rate of transfer of charges through a circuit is called?
Answer
Current
98) The filament of electric bulb is made up of :
Answer
Tungsten
99) When a vibrating tuning fork is placed on a table, a loud sound is heard. This is due to –
Answer
forced vibrations
100) Mud houses are cooler in summers and warmer in winters as compared to brick houses because –
Answer
mud is a bad conductor
101) Night photography and photography in mist and fog are possible using –
Answer
infra-red radiation
102) An Athlets runs before long jump to get advantage on –
Answer
Inertia of motion
103) In sunlight, a rose appears red. In green light, the same rose appears –
Answer
black
104) The sparkling of a diamond is due to –
Answer
total internal reflection of light
105) Ocean currents are an example of –
Answer
convection
106) A piece of wood is held under water. The up thrust on it will be:
Answer
less than weight of the wood
107) For a person having hypermetropia, the near point is –
Answer
greater than 25 cm
108) Amount of water vapour in the atmosphere is measured in terms of –
Answer
Humidity
109) Name the process of production of energy in the Sun –
Answer
Nuclear fusion
110) The ozone hole that has been detected lies in the atmosphere above –
Answer
Antarctica
111) The device used to change the speed of an electric fan is –
Answer
Regulator
112) Why is it difficult to breathe at higher altitudes?
Answer
Due to low air pressure
113) The reason for a swimming pool to appear less deep than the actual depth is –
Answer
Refraction
114) Alternating current is converted into direct current by a –
Answer
Rectifier
115) Remote-sensing device has an inbuilt source of –
Answer
Infrared ray
116) The atmosphere is heated mainly by –
Answer
Radiation
117) The atmospheric layer reflecting radio waves is called –
Answer
Ionosphere
118) 'Cryogenics' is a science dealing with –
Answer
low temperatures
119) Heat from the Sun reaches the Earth by –
Answer
Radiation
120) The commonly used thermometric substance is _.
Answer
Mercury
121) Gamma rays can cause –
Answer
gene mutation
122) A transformer works on the principle of –
Answer
Mutual induction
123) Who defined the law of gravitation?
Answer
Newton
124) What is colour of light related to?
Answer
Amplitude
125) What principle/law explains the working of the hydraulic brakes in automobiles?
Answer
Pascal's law
126) The material which can be deformed permanently by heat and pressure is called a:
Answer
Thermoset
127) The mass of a star is two times the mass of the Sun. How it will come to an end?
Answer
Neutron Star
128) If the diameter of a capillary is doubled, then the rise of water in it will be –
Answer
half
129) The substance which conducts current in the solid state is –
Answer
graphite
130) Newton is used to measure .
Answer
Force
131) The mass density of Kerosene is:
Answer
Less than water
132) Water is a good solvent of ionic salts because -
Answer
It has a high dipole moment
133) For which type of motion, the distance time graph is not a straight line and can be any kind of curve?
Answer
Non-uniform motion
134) A device used for converting a.c. into d.c. is called –
Answer
Rectifier
135) Energy of Ultraviolet rays is great than –
Answer
Infra-red rays
136) The surface temperature of the Sun is nearly -
Answer
6000K
137) Light year is a unit of -
Answer
distance
138) The strongest force in nature is –
Answer
Nuclear force
139) Fog is an example of –
Answer
Liquid dispersed in gas
140) 'SONAR' is mostly used by -
Answer
Navigators
141) Electrostatic precipitator is used to control —
Answer
Air pollution
142) The time period of a second’s pendulum is –
Answer
2 seconds
143) Persistance of vision is the principle behind –
Answer
Cinema
144) Metals are good conductors of electricity because –
Answer
they contain free electrons
145) Formation of shadows can be explained by -
Answer
rectilinear propagation of light
146) The absolute zero is a temperature at which -
Answer
Molecular motion in a gas would cease
147) An aircraft can perform aerobatic manoeuvres in a vertical loop because of-
Answer
gravity
148) A photostat machine works on –
Answer
electrostatic image making
149) If a copper wire is increased to double its length, its resistance will become –
Answer
double
150) In a diesel engine the high temperature needed to ignite the fuel is achieved by –
Answer
compressing air in the cylinders
151) To measure the speed of an approaching car a police officer shines –
Answer
radio waves on it
152) A person wears spectators with concave lenses. It means that normally (when not using glasses), the image of distant objects is focused in his eyes –
Answer
in front of the retina
153) Ohm's law defines –
Answer
a resistance
154) Lakes freeze in cold countries in winter, leaving the water underneath at –
Answer
4°C
155) Light from the Sun reaches us in nearly -
Answer
8 minutes
156) Second’s pendulum is a pendulum which executes one oscillation in:
Answer
Two seconds
157) Sound cannot pass through –
Answer
Vacuum
158) The instrument used to measure the speed of the wind is –
Answer
Anemometer
159) An optically plane surface reflects a beam of light –
Answer
as a parallel beam in one direction
160) The slope of a velocity-time graph represents –
Answer
acceleration
161) The material which can be deformed permanently by heat and pressure is called a -
Answer
thermoset
162) On planet Earth, there is no centrifugal force at the –
Answer
Poles
163) Gas thermometers are more sensitive than the liquid thermometers because of the gases -
Answer
have low specific heat
164) The earth-wire of a cable is connected to –
Answer
the fuse of the appliance
165) The metal used to make lightning conductors is –
Answer
Copper
166) The phenomenon of radioactivity was discovered by -
Answer
Henri Becquerel
167) If the velocity-time graph of a particle is represented by y = mt + c, then the particle is moving with–
Answer
constant acceleration
168) In a photocell light energy is converted into –
Answer
Electrical energy
169) A storm is predicted if atmospheric pressure –
Answer
Falls suddenly
170) The smallest unit of classification is -
Answer
Species
171) Light from the Sun reaches us in nearly -
Answer
8 minutes
172) A concave lens always forms an image which is –
Answer
Virtual and erect
173) One can distinguish a telescope from a microscope by observing –
Answer
length and size of the lens
174) The sound produced by a bat is –
Answer
ultrasonic
175) The image of an object formed on the retina of the eye is -
Answer
real and inverted
176) Suns heat reaches us by –
Answer
Radiation
177) A colour-blind person cannot –
Answer
Distinguish between certain colours
178) Forged documents are detected by –
Answer
ultraviolet rays
179) In which medium, velocity of sound is maximum?
Answer
Metals
180) If two bodies of different masses, initially at rest, are acted upon by the same force for the same time, then the both bodies acquire the same -
Answer
momentum
181) The compound of a metal found in nature is called -
Answer
Mineral
182) Decibel is used to measure the intensity of -
Answer
Sound
183) Rainbow is seen after rain because of hanging molecules of water which act as –
Answer
mirrors
184) Water is used in car radiator because of its –
Answer
high specific heat capacity
185) If a metal can be drawn into wires relatively easily it is called:
Answer
ductile
186) At what temperature a body will not radiate any heat energy?
Answer
-273° C
187) The mirror used for the head light of a car is –
Answer
parabolic concave
188) Knot is a measure of -
Answer
Unit of speed
189) Stereo was invented by .
Answer
Alan Blumlein
190) How much mechanical work must be done to completely melt 1 gram of ice at 0°C?
Answer
80 J
191) A bullet is fired from a rifle which recoils after firing. The ratio of kinetic energy of the rifle to that of the bullet is –
Answer
zero
192) At low temperature, Lead behaves as a :
Answer
Super conductor
193) At what temperature are the temperature on Celsius and Fahrenheit scales equal?
Answer
-40° Celsius
194) The electric charge is stored in a device called:
Answer
Capacitor
195) SI unit for the surface tension is .
Answer
N/m
196) The density of the liquid when heated –
Answer
decreases
197) The distance between node and adjacent antinodes is 30 cm. The wavelength is -
Answer
60 cm.
198) When a bar magnet is cut into two equal halves, the pole strength of each piece –
Answer
remains the same
199) A new technology which provides the ability to create an artificial world and have people interact with it is called –
Answer
Virtual reality
200) A proton is identical to _.
Answer
a beta particle
201) What should a person on a freely rotating turn table do to decrease his (angular) speed?
Answer
Spread his hands outwards
202) In a rechargeable cell what kind of energy is stored within the cell?
Answer
Chemical energy
203) Danger signals are generally red as red light –
Answer
undergoes least deviation
204) A simple microscope consists of :
Answer
a short focus convex lens
205) A passenger standing in a bus is thrown outward when the bus takes a sudden turn. This happens due to –
Answer
Inertia of motion
206) When pressure is increased the melting point of ice –
Answer
decreases
207) What apparatus is used to locate a submerged object?
Answer
Sonar
208) The instrument which uses sound waves to measure the depth of oceans is –
Answer
Sonar
209) One Kilowatt hour is equal to—
Answer
3.6 Mega Joule
210) Longitudinal waves cannot travel through –
Answer
Vacuum
211) Electrostatic precipitator is used to control the pollution of –
Answer
air
212) The device which converts AC to DC is –
Answer
Rectifier
213) What is the minimum escape velocity of rocket to be launched into space?
Answer
11 Km/Sec.
214) How much calories of energy is released by a boiled egg?
Answer
77
215) Which combination of colour is the most convenient during day and night time?
Answer
Red and green
216) The instrument that measures and records the relative humidity of air is –
Answer
Hygrometer
217) Smog is a combination of –
Answer
Smoke and fog
218) When white light passes through a glass prism we get a spectrum on the other side of the prism. In the emergent beam the ray which is deviated least is -
Answer
the red ray
219) Study of life in outer space is known as -
Answer
exobiology
220) Lens is made up of –
Answer
Flint glass
221) The time period of a pendulum when taken to the Moon would:
Answer
increase
222) Pieces of camphor placed on water move about rapidly. This is because of -
Answer
surface tension
223) Lightning is caused due to –
Answer
electric discharge
224) Sprayer functions on –
Answer
Bernouli’s principle
225) Waves that are required for long distance wireless communication are –
Answer
Radio waves
226) Rise of oil a wick is due to –
Answer
surface tension of the oil
227) Heat stored in water vapour is –
Answer
latent heat
228) The layer of atmosphere used for radio-wave transmission is –
Answer
ionosphere
229) SI unit of luminous intensity is .
Answer
candela
230) A rear-view mirror for driving is –
Answer
convex
231) A periscope works on the principle of –
Answer
total internal reflection
232) A copper disc has a hole. If the disc is heated, the size of the hole -
Answer
increases
233) Water cannot be used to extinguish fire caused by electric current, because –
Answer
it may cause electrocution
234) The radiation initially produced in fluorescent tube is –
Answer
ultraviolet
235) The 'four stroke petrol engine' is based on –
Answer
Otto-cycle
236) The device which transfer the signal from low resistance region to high resistance region is –
Answer
transistor
237) A rubber ball is dropped from a height of 2 metres. To what height will it rise if there is no loss of energy/velocity after rebounding?
Answer
2 metres
238) The atmospheric air is held to the Earth by –
Answer
gravity
239) Atomic power plant works on the principle of –
Answer
Fission
240) Spectacles used for viewing 3D films have –
Answer
Polaroid
241) If the temperature of a place increases suddenly, the relative humidity –
Answer
Decreases
242) Pulsars are :
Answer
rapidly spinning stars
243) Tungsten is used for the manufacture of the filament of an electric bulb, because –
Answer
It has a very high melting point
244) What is the wavelength of visible spectrum?
Answer
3900 A° - 7600 A°
245) The shape of our Milky Way galaxy is –
Answer
spiral
246) The different colours of different stars are due to the variation of –
Answer
temperature
247) The splitting of different colours of light in a prism is :
Answer
Dispersion light
248) A boat will submerge when it displaces water equal to its own:
Answer
weight
249) Anemometer is used to measure –
Answer
wind velocity
250) The device used for locating submerged objects under sea is –
Answer
sonar
251) The working principle of a 'Washing machine' is :
Answer
centrifugation
252) Instrument used to measure the force and velocity of the wind is –
Answer
Altimeter
253) Who measured the velocity of light first?
Answer
Romer
254) Heat from the sun reaches earth by the process of –
Answer
Radiation
255) Boyle's law is a relationship between –
Answer
Pressure and volume
256) Flemings right hand rule is used to find the direction of the –
Answer
Induced current
257) What is the full form of 'AM' regarding radio broadcasting?
Answer
Amplitude Modulation
258) Bolometer is used to measure –
Answer
Temperature
259) Supersonic plane fly with the speed -
Answer
greater than the speed of sound
260) If input frequency of a full wave rectifier be n, then output frequency would be -
Answer
2n
261) Heat transfer horizontally within the atmosphere is called –
Answer
Advection
262) The phenomenon of light associated with the appearance of blue colour of the sky is –
Answer
Scattering
263) Air coolers are more suitable for –
Answer
hot and dry climate
264) Who enunciated the laws of planetary motion?
Answer
Johannes Kepler
265) The radiant energy having lowest energy is –
Answer
microwave radiation
266) When water is heated from 0°C to 10°C. Its volume :
Answer
first decreases and then increases
267) Natural radioactivity was discovered by -
Answer
Henri Becquerel
268) A circular plate, a cube and a sphere, all made up of same material and having the same mass, are heated to 300°C and left in a room. Which of them will have the slowest rate of cooling?
Answer
Sphere
269) The 'Abolition of Titles' is a fundamental right classified under:
Answer
Right to equality
270) A player making a long jump is an example of .
Answer
Projectile motion
271) When hot-water is sprinkled on a hotter glass tumbler, it breaks because –
Answer
glass suddenly contracts
272) Electricity is transmitted over long distances –
Answer
there is less wastage of energy
273) If in a motion, the axis of the rotation passes through an object, then the motion is called.
Answer
Spin motion
274) Noise is measured in –
Answer
Decibel
275) If ice floating on water in a vessel melts, the water level in the vessel .
Answer
does not change
276) ATM stands for –
Answer
Automatic Teller Machine
277) The first synthetic fibre made by man was-
Answer
Nylon
278) Compared to fresh Water, the freezing point of sea water is -
Answer
Lower
279) Which colour is the complementary colour of yellow?
Answer
Blue
280) The sudden fall of atmospheric pressure indicates –
Answer
storm
281) The energy emitted by the Sun is due to –
Answer
Nuclear fusion
282) The sky appears blue because of –
Answer
Scattering of light
283) The metal whose electrical conductivity is more, is –
Answer
silver
284) What happens to a liquid, when the vapour pressure equals the atmospheric pressure?
Answer
The liquid boils
285) Why do brads not have respiratory trouble at the time of flying at high all?
Answer
They have extra air sacs
286) The temperature which has the same reading on both Fahrenheit and Celsius scales is –
Answer
-400
287) Kilowatt-hour is the unit of :
Answer
Energy
288) In nuclear reactor, heavy water is used as –
Answer
moderator
289) Tear gas used by the police to disperse the mob contains –
Answer
chlorine
290) Mist is caused by –
Answer
water vapour at low temperature
291) The ozone layer in the atmosphere is at a height of about .
Answer
50 km
292) The part of the eye having the largest refractive index is :
Answer
lens
293) Conversion of heat into electrical er is achieved by using –
Answer
Thermocouple
294) The filament of electric bulb is made of -
Answer
Tungsten
295) Necessary element of change in solar energy to electric energy –
Answer
Silicon
296) Electric current in a metal wire is due to the flow of —
Answer
Electrons
297) Which type of reaction produces the most harmful radiation?
Answer
Fission reaction
298) Optic fibres are used in :
Answer
Endoscopy
299) Two waves, each of amplitude 1.5 mm and frequency 10 Hz, are travelling in opposite direction with a speed of 20 mm/s. The distance in mm between adjacent nodes is :
Answer
1
300) While catching a ball, a player pulls down his hands to lower the –
Answer
momentum
301) A camera uses a to form an image on a piece of film at the back.
Answer
convex lens
302) In 1866, John Newlands, an English scientist, arranged the then known elements in the order of increasing atomic masses. He found that every eighth element had properties similar to that of the first. He called it the -
Answer
Law of Octaves
303) Magnetism in materials is due to -
Answer
circular motion of electrons
304) The outermost layer of the Sun is called -
Answer
corona
305) During washing of clothes, we use indigo due to its –
Answer
Proper pigmental composition
306) Light year is a unit of -
Answer
distance
307) Heat is transmitted from higher temperature to lower temperature through the actual motion of the molecules in -
Answer
Convection
308) Water drops are spherical because of -
Answer
surface tension
309) If the temperature of a piece increases suddenly, the relative humidity–
Answer
decreases
310) What changes will happen to a bowl of ice and water kept at exactly zero degree Celsius?
Answer
No change will happen
311) Curie point is the temperature at which –
Answer
A metal loses magnetic properties
312) When a bottle of perfume is opened in one corner of a room the smell spreads soon throughout the room. This is an example of -
Answer
surface tension
313) The material used in the fabrication of a transistor is –
Answer
Silicon
314) If there is a circular hole in a metal plate, what happens to the radius of the hole when the plate is heated?
Answer
Increases
315) The velocity of sound is more in –
Answer
steel
316) Radioactivity is due to –
Answer
unstable nucleus
317) Which conservation principle is applicable in the case of the motion of a rocket?
Answer
Conservation of momentum
318) These waves cannot be transmitted through vacuum –
Answer
Sound
319) A gap is left between two rails of a railway track to accommodate of the metal.
Answer
liner expansion
320) If an ordinary glass tube and a glass capillary tube are 'both clipped in a beaker of water, water rises in –
Answer
both
321) Optical fibres are based on the phenomenon of –
Answer
Total Internal Reflection
322) Who was the inventor of frozen foods?
Answer
Clarence Birdseye
323) The clouds float in the atmosphere because of their low:
Answer
density
324) A person is hurt on kicking a stone due to –
Answer
Reaction
325) The fuse in our domestic electric circuit melts when there is a high rise in –
Answer
Current
326) The energy stored in a watch spring is –
Answer
Potential energy
327) Cryogenics is a science deals with -
Answer
Low Temperature
328) `Short-sight' in human eye can be corrected by using proper –
Answer
concave lens
329) What is the reason for twinkling of stars?
Answer
Atmospheric refraction
330) Which gas is used in filling electric bulbs -
Answer
Argon
331) Ball pen functions on the principle of :
Answer
Surface tension
332) A man cannot see clearly beyond 10 meters. The disease he suffers from :
Answer
Myopia
333) The S.I. unit of electric charge is –
Answer
coulomb
334) Light beam which is highly directional is called:
Answer
laser
335) Permissible noise level at Residential area during night time is :
Answer
45 dB
336) When milk is churned, the cream separates from it clue to:
Answer
Centrifugal force
337) Moving electric charge produces -
Answer
magnetic field
338) The process of union of two or more molecules of a substance to form a large single molecule is called :
Answer
Polymerization
339) When a barometer reading suddenly recedes, it indicates that climate –
Answer
will be extremely stormy
340) Which colour of light shows maximum deviation when passed through a prism?
Answer
Violet
341) The best material for the core of a transformer is –
Answer
soft iron
342) Electron microscope was invented by –
Answer
Knoll and Ruska
343) Hydrogen bomb is based on the principle of -
Answer
Nuclear fusion
344) The period of revolution of a geostationary satellite is –
Answer
24 hours
345) The device which converts sound energy into electrical enemy is called –
Answer
Microphone
346) The light rays used for eliminating bacteria –
Answer
ultra-violet radiation
347) The audio signals of TV are –
Answer
Frequency modulated
348) Red light is used for signals because it has –
Answer
long wavelength
349) The washing machine works on the principle of -
Answer
Centrifugation
350) Which zone of a candle flame is the hottest?
Answer
Middle luminous zone
351) 'Hydraulic brakes' work on the principle of –
Answer
Pascal's law
352) The instrument for measuring intensity of earthquakes is called –
Answer
Seismograph
353) ‘Therm' is the unit of –
Answer
Heat
354) Newton's first law of motion gives the concept of –
Answer
Inertia
355) When heated from 0° to 10°C volume of a given mass of water will -
Answer
Decrease and after will increase
356) It is difficult to cook rice –
Answer
at the top of a mountain
357) Angle of friction and angle of repose are –
Answer
Equal to each other
358) If a boy sitting in a train, which is moving at a constant velocity, throws a ball straight up into the air, the ball will –
Answer
Fall into his hand
359) A metal plate with a circular hole at the centre is heated. What will happen to the area of the hole?
Answer
Increase
360) Stars in the sky appear to twinkle due to –
Answer
a series of refractions
361) A pilot has to release the bomb to hit a target –
Answer
before the target
362) Parabolic mirros are used in –
Answer
Car headlights
363) Which atmospheric layer contains ozone layer?
Answer
Stratosphere
364) Water flows through a horizontal pipe at a constant volumetric rate. At a location where the cross sectional area decreases, the velocity of the fluid:
Answer
increases
365) Rate of change of momentum is -
Answer
Force
366) An ice block with a piece of lead embedded in it floats in water. If ice melts the water level –
Answer
Falls
367) The frequency of ultrasound wave is typically –
Answer
Below 20 kHz
368) Intensity of gravitational field of earth is maximum at –
Answer
Poles
369) The spokes used in the wheel of a bicycle increase its –
Answer
Moment of inertia
370) A soap bubble shows colours when illuminated with white light. This is due to –
Answer
Interference
371) A boy sitting in an open car moving with the constant speed throws a ball straight up into the air. The ball falls –
Answer
Behind him
372) The process involved in making soap is –
Answer
Saponification
373) A pond of water appears less deep due to –
Answer
Refraction
374) The oldest type of energy known to man is –
Answer
Geothermal energy
375) The source of the sun's energy is the process of –
Answer
Nuclear fusion
376) In the atmosphere ultraviolet rays are absorbed by –
Answer
Oxygen
377) When a bottle of scent is kept open in a corner of a room its odour is felt in all parts of the room. This is clue to the phenomenon of –
Answer
diffusion
378) Clear nights are colder than cloudy nights because of –
Answer
radiation
379) In AC circuits, AC meters measure –
Answer
rms values
380) When a light wave is reflected from a mirror, there is a change in its –
Answer
amplitude
381) A body absorbs heat most if it is –
Answer
black and rough
382) How many terminals do an electric cell has?
Answer
2
383) Water from soil enters into the root hairs owing to :
Answer
Capillary pressure
384) The unit of electrical power is –
Answer
Watt
385) The scientist who first sent electromagnetic waves to distant places is –
Answer
Thomas Alva Edison
386) Conversion of chemical energy into electrical energy occurs in –
Answer
a battery
387) Damp clothes are dried in spin dryers by the action of –
Answer
centrifugal forces
388) Which colour of light shows maximum deviation when passed through a prism?
Answer
Violet
389) The resistance of the human body (dry condition) is of the order of –
Answer
None of these
390) The sharpness of a television image is termed as its –
Answer
Resolution
391) 0°K is equivalent to
Answer
-273°C
392) What is the telescope designed to search for earth-size planets in the nearby region of our galaxy, termed as?
Answer
Hubble telescope
393) Which law is also called the law of inertia?
Answer
Newton's first law
394) Ohm’s law obeyed in -
Answer
a metallic conductor
395) Solar energy is due to –
Answer
fusion reactions
396) The plastic material commonly used for making gear wheels is –
Answer
Nylons
397) The nuclear force is -
Answer
Short range attractive force
398) The angle in which a cricket ball should be hit to travel maximum horizontal distance is :
Answer
45° with horizontal
399) The minimum number of geostationary satellites needed for un-interrupted global coverage is :
Answer
2
400) Which type of mirror is used in the head lights of vehicles?
Answer
Concave mirror
401) The height of a geostationary satellite from the Earth's surface is approximately:
Answer
36,000 km
402) Shaving mirror is –
Answer
Concave
403) Magnifying Glass is basically a –
Answer
Convex lens
404) The velocity of heat radiation in vacuum is –
Answer
Equal to that of light
405) The working principle of a washing machine is :
Answer
centrifugation
406) The hydraulic brake used in automobiles is a direct application of -
Answer
Pascal's law
407) Longitudinal waves and Transverse waves are types of -
Answer
Mechanical waves
408) Due to rusting the weight of iron -
Answer
Increases
409) Water will not be vaporized if –
Answer
the humidity is 100%
410) Decibel is a term connected with :
Answer
sound
411) As we go from Equator to North pole the value of `g’, the acceleration due to gravity –
Answer
increases
412) Flight Recorder is technically called :
Answer
Black box
413) The part of the eye having the largest refractive index is -
Answer
lens
414) The centre of gravity of a sprinter during the race lies –
Answer
Ahead of his feet
415) The hair of shaving brush clings together when removed from water due to –
Answer
Surface tension
416) If a current of 1.5 A is maintained in a resistor of 10 2, then the energy dissipated in the resistor in 1 minute will be :
Answer
1350 W
417) Submerged objects can be located using –
Answer
Sonar
418) A solid ball of metal has a spherical cavity inside it. When the ball is heated the volume of the cavity will -
Answer
Increase
419) Where are mesons found?
Answer
Cosmic rays
420) A larger force on a rotating body results in larger _.
Answer
Axis of rotation
421) The instrument used to see the distant objects on the Earth is –
Answer
Terrestrial telescope
422) A current carrying conductor is associated with –
Answer
an electro-magnetic field
423) The weakest of all fundamental forces is –
Answer
Gravitational force
424) A micron is equal to –
Answer
0.001 mm
425) Persons suffering from myopia are advised to use –
Answer
concave lens
426) If cream is removed from milk, its density –
Answer
Increases
427) A piece of ice is floating in water kept in a beaker. When all the ice melts the level of water will -
Answer
remain the same
428) A steam engine converts the heat energy of steam into .
Answer
Mechanical energy
429) A boy is standing in front of a plane mirror at a distance of 3 m from it. What is the distance between the boy and his image?
Answer
6 m
430) Loudness of sound varies directly with vibrating body’s –
Answer
Amplitude
431) A thin oil film on a water surface appears coloured because of –
Answer
interference
432) Iron which resembles Cobalt and Nickel in properties has been placed far away from these elements. This was one of the limitations of :
Answer
Newland's law of octaves
433) How much is the difference of time between any two Consecutive longitudes?
Answer
4 min
434) At boiling point of liquids, its –
Answer
Temperature remains constant
435) Newton's first law is also known as _.
Answer
Law of Inertia
436) The humidity of air measured in percentage is called -
Answer
relative humidity
437) Who developed the theory of Evolution?
Answer
Charles Darwin
438) Name the process by which bubbles from liquid are formed?
Answer
Effervescence
439) 'Parsec' is the unit measurement of –
Answer
Astronomical distance
440) The phenomenon of change in direction of light when it passes from one medium to another is called -
Answer
Refraction
441) The mercury and sodium street lamps light up because of –
Answer
Atomic emission
442) Instrument for measuring wind velocity is called –
Answer
Anemometer
443) Who invented the Lightning Rod in 1749?
Answer
Benjamin Franklin
444) The 'Greenhouse effect' is mainly due to increase in atmospheric –
Answer
Carbon dioxide
445) Matter waves are –
Answer
de Broglie waves
446) When the milk is churned vigorously the cream from it is separated out clue to –
Answer
Centrifugal force
447) The temperature at which the catalytic activity of the catalyst is maximum, is called -
Answer
optimum temperature
448) Which instrument is used to record Atmospheric pressure?
Answer
Barometer
449) Full form of CFL used in place of electric bulbs is –
Answer
compact fluorescent lamp
450) A light year is a unit of –
Answer
distance
451) An instrument that records earth-quakes is –
Answer
Seismograph
452) An object is in static equilibrium when it is .
Answer
at rest
453) The study of phenomena at very low temperatures is called -
Answer
cryogenics
454) Steel is more elastic than rubber because it –
Answer
is deformed very easily
455) Which phenomena shows the particle nature of light?
Answer
Photoelectric effect
456) In the names Mangifera indica (mango), Solanum tuberosum (potato) and Panthera leo (lion), the terms Mangifera, Solanum and Panthera represent the higher level of?
Answer
Taxon
457) Sound waves in air are .
Answer
longitudinal
458) The motion of a body that repeats itself after a regular interval of time is –
Answer
a periodic motion
459) When a strong beam of light is passed through a colloidal solution, the light will –
Answer
be scattered
460) The pitch of sound depends on its –
Answer
Frequency
461) The ozone layer protects us from -
Answer
Ultra violet rays
462) Entropy of the universe is -
Answer
continuously increasing
463) Cylindrical lens is used by a person suffering from -
Answer
astigmatism
464) Metals are good conductors of electricity because -
Answer
they contain free electrons
465) Speed of sound in solids is -
Answer
15 times that in gas/ 15
466) To open a door easily, the handle should be fixed –
Answer
None of these
467) Dioptere is the unit of –
Answer
power of a lens
468) Velocity of sound in air does not depend on –
Answer
Pressure of air
469) Conversion of sound energy into electrical energy is done by –
Answer
Microphone
470) The theory of inheritance of acquired characters was propounded by -
Answer
J. B. Lamarck
471) A jet engine works, on the principle of conservation of -
Answer
linear momentum
472) Which electromagnetic radiation is used for satellite communication?
Answer
Microwave
473) Solar cells work on the principle of –
Answer
photovoltaic effect
474) When a piece of stone is immersed in water, it displaces water of equal –
Answer
Mass
475) Efficiency of the catalyst depends on its -
Answer
number of free valencies
476) The oil in the wick of lamp rises due to –
Answer
Pheonomenon of capillarity
477) Number of basic SI unit is _.
Answer
7
478) Optical fibre works on the -
Answer
total internal reflection
479) Gas thermometers are more sensitive than the liquid thermometers because the gases –
Answer
have large coefficient of expansion
480) A man standing on a edge of a cliff throws a stone vertically upwards with a certain speed. He then throws another stone downwards with the same speed. Find the ratio of the speeds of the two stones when they hit the ground.
Answer
1 : 1
481) The locomotion of insects to the source of light is called :
Answer
Phototropic
482) The splitting of white light into its components is due to:
Answer
Dispersion
483) The moment of inertia of a body does not depend upon its –
Answer
angular velocity
484) The speed of light will be minimum while passing through -
Answer
glass
485) is the cell organelle, in which the biochemical processes of respiration and energy production occur.
Answer
Mitochondria
486) Amount of water vapour in a unit volume (Cubic metre) of air is called:
Answer
absolute humidity
487) Which waves cannot be transmitted through vacuum -
Answer
Sound
488) Super cooling stands for cooling of a liquid –
Answer
below freezing point
489) Alcohol is more volatile than water because is lower than water.
Answer
its boiling point
490) The boiling point of water depends upon the –
Answer
atmospheric pressure
491) The loudness of sound depends upon .
Answer
Wavelength
492) If no external force acts on a system of bodies, the total linear momentum of the system of bodies remains constant. Which law states this?
Answer
Principle of conservation of linear momentum
493) When net torque is zero, will be constant -
Answer
angular momentum
494) Elecronegativity is the measure of -
Answer
Non-metallic character
495) If the angle of incidence formed on a concave mirror at a point is 30° then the angle of reflection will be:
Answer
30°
496) The rotational effect of a force on a body about an axis of rotation is described in terms of the -
Answer
Moment of force
497) Radian per second is unit of _.
Answer
Angle Velocity
498) Sound of frequency below 20 Hz is called .
Answer
infrasonic
499) What is the phenomenon which established the transverse nature of light?
Answer
Polarisation
500) During combustion of unsaturated compounds a is seen.
Answer
yellow flame