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question_answer1)
Chadwick was awarded the 1935 Nobel prize in physics for his discovery of the
A)
electron done
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B)
proton done
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C)
neutron done
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D)
positron done
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question_answer2)
The process of superimposing signal frequency (i.e., audio wave) on the carrier wave is known as
A)
Transmission done
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B)
Reception done
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C)
Modulation done
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D)
Detection done
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question_answer3)
Electromagnetic radiations are emitted by which of the following? [NDA]
A)
Only by radio and television transmitting antennas done
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B)
Only by bodies at temperature higher than their surroundings done
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C)
Only by red-hot bodies done
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D)
By all bodies done
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question_answer4)
If an a-particle is projected normally through a uniform magnetic field, then the path of the a-particle inside the field will be [NDA]
A)
circular done
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B)
parabolic done
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C)
elliptical done
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D)
a straight line done
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question_answer5)
Which one of the following is correct? [NDA] |
The wavelength of the X-rays |
A)
is longer than the wavelength of sound waves done
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B)
is longer than the wavelength of the yellow sodium light done
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C)
is longer than the wavelength of radio waves done
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D)
is of the order of 0.1 nanometer done
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question_answer6)
Light Emitting Diode (LED) converts [CDS]
A)
light energy into electrical energy done
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B)
electrical energy into light energy done
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C)
thermal energy into light energy done
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D)
mechanical energy into electrical energy done
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question_answer7)
Television signal cannot be received generally beyond a particular distance due to [CDS]
A)
curvature of the Earth done
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B)
weakness of antenna done
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C)
weakness of signal done
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D)
absorption of signal in air done
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question_answer8)
Sun emits energy in the form of electromagnetic radiation. The following help in the generation of solar energy. Arrange them in the right sequence beginning from the starting of the cycle: [NDA]
1. Hydrogen is converted to helium at very high temperatures and pressures. |
2. The energy finds its way to sun's surface. |
3. A vast quantity of energy is generated by nuclear fusion. |
Select the correct answer using the code given below.
A)
1-2-3 done
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B)
2-3-1 done
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C)
3-2-1 done
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D)
1-3-2 done
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question_answer9)
Consider the following statements: [IAS Prelim] |
At the present level of technology available in India, solar energy can be conveniently used to: |
1. Supply hot water to residential buildings. |
2. Supply water for minor irrigation projects. |
3. Provide street lighting. |
4. Electrify a cluster of villages and small towns. |
A)
1, 2, 3 and 4 are correct done
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B)
2 and 4 are correct done
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C)
1 and 3 are correct done
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D)
1, 2 and 3 are correct done
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question_answer10)
The neutron, proton, electron and alpha particle are moving with equal kinetic energies. How can the particles be arranged in the increasing order of their velocities? [NDA]
A)
alpha particle-neutron-proton- electron done
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B)
proton-electron-neutron-alpha particle done
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C)
electron-proton-neutron-alpha particle done
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D)
neutron-proton-electron-alpha particle done
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question_answer11)
Match the Column I and Column II.
|
Column -1 |
|
Column - II |
[A] |
Isotopes |
(1) |
Mass number same but different atomic number |
[B] |
Isobars |
(2) |
Atomic number same but different mass number. |
[C] |
Isotones |
(3) |
Number of neutrons plus number of protons |
[D] |
Nucleons |
(4) |
Number of neutrons same but different atomic number |
A)
[A] \[\to \] (3); [B] \[\to \] (1); [C] \[\to \] (2); [D] \[\to \] (4) done
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B)
[A] \[\to \] (2); [B] \[\to \] (1); [C] \[\to \] (4); [D] \[\to \] (3) done
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C)
[A] \[\to \] (1); [B] \[\to \] (2); [C] \[\to \] (3); [D] \[\to \] (4) done
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D)
[A] \[\to \] (1); [B] \[\to \] (3); [C] \[\to \] (2); [D] \[\to \] (4) done
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question_answer12)
Select the correct statement(s) from the following.
I. In conductors, the valence and conduction bands may overlap. |
II. Substances with energy gap of the order of 10 eV are insulators. |
III. The resistivity of a semiconductor increases with increase in temperature. |
IV. The conductivity of a semiconductor increases with increase in temperature. |
A)
I and II only done
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B)
I and III only done
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C)
I, II and IV done
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D)
I, II, III and IV done
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question_answer13)
Which of the following cannot be fabricated on an IC? [CDS]
A)
Transistors done
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B)
Inductors and transformers done
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C)
Diodes done
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D)
Resistors done
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question_answer14)
At absolute zero, Si acts as
A)
non-metal done
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B)
metal done
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C)
insulator done
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D)
None of these done
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question_answer15)
Telephony is an example of _____ mode of communication
A)
point-to-point done
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B)
broad cast done
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C)
both [a] and [b] done
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D)
None of these done
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question_answer16)
|
Column-I |
|
Column-II |
[A] |
Hydrogen bomb |
(1) |
Fission |
[B] |
Atom bomb |
(2) |
Fusion |
[C] |
Binding energy |
(3) |
Critical mass |
[D] |
Nuclear reactor |
(4) |
Mass defect |
A)
[A] \[\to \] (3); [B] \[\to \] (2); [C] \[\to \] (1); [D] \[\to \] (4) done
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B)
[A] \[\to \] (2); [B] \[\to \] (1); [C] \[\to \] (4); [D] \[\to \] (3) done
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C)
[A] \[\to \] (3); [B] \[\to \] (1); [C] \[\to \] (2); [D] \[\to \] (4) done
clear
D)
[A] \[\to \] (4); [B] \[\to \] (2); [C] \[\to \] (3); [D] \[\to \] (1) done
clear
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question_answer17)
Which of the following statements is/are correct?
I. Pure Si doped with trivalent impurities gives a p-type semiconductor |
II. Majority carriers in a n-type semiconductor are holes |
III. Minority carriers in a p-type semiconductor are electrons |
IV. The resistance of intrinsic semiconductor decreases with increase of temperature |
A)
I only done
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B)
I, III and IV done
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C)
I and IV done
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D)
II only done
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question_answer18)
The active component in an IC are
A)
Resistors done
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B)
Capacitors done
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C)
Transistors and diodes done
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D)
None of these done
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question_answer19)
The waves used in telecommunication are [SSC]
A)
IR done
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B)
UV done
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C)
Microwave done
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D)
Cosmic rays done
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question_answer20)
Audio signal cannot be transmitted because
A)
the signal has more noise done
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B)
the signal cannot be amplified for distance communication done
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C)
the transmitting antenna length is very small to design done
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D)
the transmitting antenna length is very large and impracticable done
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question_answer21)
Television signals are
A)
frequency modulated done
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B)
amplitude modulated done
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C)
both frequency and amplitude modulated done
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D)
phase modulated done
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question_answer22)
Repeaters used in telephone links are: [NDA]
A)
Rectifiers done
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B)
Oscillators done
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C)
Amplifiers done
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D)
Transformers done
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question_answer23)
The transistor are usually made of [CDS]
A)
metal oxides with high temperature coefficient of resistivity done
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B)
metals with high temperature coefficient of resistivity done
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C)
metals with low temperature coefficient of resistivity done
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D)
semiconducting materials having low temperature coefficient of resistivity done
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question_answer24)
A moderator is used in nuclear reactors in order to
A)
slow down the speed of the neutrons done
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B)
accelerate the neutrons done
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C)
increase the number of neutrons done
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D)
decrease the number of neutrons done
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question_answer25)
The main constituent of biogas is
A)
methane done
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B)
carbon dioxide done
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C)
hydrogen done
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D)
hydrogen sulphide done
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question_answer26)
_____ is used as a fuel in space ships.
A)
Hydrogen done
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B)
Alcohol done
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C)
Petrol done
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D)
Diesel done
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question_answer27)
Propane is used instead of natural gas on many farms and in rural areas. Why is propane often used instead of natural gas?
A)
It's safer done
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B)
It's portable done
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C)
It's cleaner done
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D)
It's cheaper done
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question_answer28)
Which one of the following is the correct sequence of the wavelengths of radiations? [NDA]
A)
UV > Green> IR > Hard X-rays done
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B)
IR > Green> UV > Hard X-rays done
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C)
UV > Hard X-rays> IR > Green done
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D)
IR > Hard X-rays> Green> UV done
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question_answer29)
The most familiar form of radiant energy in sunlight that causes tanning and sun burning of human skin, is called [CDS]
A)
ultraviolet radiation done
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B)
visible radiation done
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C)
infrared radiation done
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D)
microwave radiation done
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question_answer30)
Which one among the following radiations carries maximum energy? [NDA]
A)
Ultraviolet rays done
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B)
Gamma-rays done
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C)
X-rays done
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D)
Infra-red rays done
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question_answer31)
In a hydro power plant
A)
potential energy possessed by stored water is converted into electricity done
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B)
kinetic energy possessed by stored water is converted into potential energy done
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C)
electricity is extracted from water done
clear
D)
water is converted into steam to produce electricity done
clear
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question_answer32)
Which part of the solar cooker is responsible for greenhouse effect?
A)
Coating with black colour inside the box done
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B)
Mirror done
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C)
Glass sheet done
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D)
Outer cover of the solar cooker done
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question_answer33)
A perfect black body has the unique characteristic feature as [CDS]
A)
a good absorber only done
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B)
a good radiator only done
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C)
a good absorber and a good radiator done
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D)
neither a radiator nor an absorber done
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question_answer34)
The phenomenon of high and low tides and the difference in sea levels give __________.
A)
Hydel energy done
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B)
Tidal energy done
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C)
Wave energy done
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D)
Thermal energy done
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question_answer35)
Which of the following does NOT allow harmful ultraviolet radiations from the sun to reach the earth?
A)
\[{{O}_{2}}\] done
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B)
\[N{{O}_{2}}\] done
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C)
\[C{{O}_{2}}\] done
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D)
\[{{O}_{3}}\] done
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question_answer36)
Solar cells generate little amount of electricity, but are becoming popular because
A)
its raw material Silicon is available in large quantities in India done
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B)
it can be set up in remote and inaccessible hamlets without laying transmission lines done
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C)
electricity generated from solar cells can be stored and used when required done
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D)
All of these done
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question_answer37)
Geothermal energy is
A)
energy of magma inside the earth crust done
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B)
energy stored as heat in the earth done
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C)
amount of energy obtained from coal and petroleum inside earth crust. done
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D)
amount of minerals obtained from earth crust done
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question_answer38)
Tidal energy is a
A)
form of energy obtained from kinetic energy of moving ocean water done
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B)
form of energy which is obtained from the river in the form of tidal waves done
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C)
form of energy which is obtained from the lake in the form of tidal waves done
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D)
form of energy which is obtained from the ocean in the form of tidal waves. done
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question_answer39)
Which among the following statements are the requirements of good source of energy?
A. It should do a large amount of work per unit volume or mass. |
B. It should be easily accessible. |
C. It should be easy to store and transport. |
D. It should be economical. |
A)
A, B done
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B)
A, B, C done
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C)
B, C, D done
clear
D)
All of these generator. done
clear
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question_answer40)
Which of the following statement is/are the applications of photovoltaic cells?
A. They are used to detect opacity of solids, defects materials. |
B. They are used to switch on and off the street automatically |
C. They are used to compare illuminating power of two sources. |
D. To control temperature in furnaces and chemical reactions |
A)
B and C done
clear
B)
B, C, D done
clear
C)
A, B, C done
clear
D)
All of these done
clear
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