Physics

Physical World and Measurement
Kinematics
Vectors
Laws of Motion
Work, Energy and Power
Motion of System of Particles and Rigid Body
Gravitation
Properties of Bulk Matter
Thermodynamics
Behaviour of Perfect Gas and Kinetic Theory
Oscillations and Waves
Electrostatics
Current Electricity
Magnetic Effects of Current and Magnetism
Electromagnetic Induction and Alternating Currents
Electromagnetic Waves
Optics
Dual Nature of Matter and Radiation
Atoms and Nuclei
Electronic Devices & Semiconductor
Communication System
Physics

Chemistry

Some Basic Concepts of Chemistry
Structure of Atom
Classification of Elements and Periodicity in Properties
Chemical Bonding and Molecular Structure
States of Matter: Gases and Liquids
Equilibrium
Redox Reactions
Hydrogen
s-Block Element (Alkali and Alkaline earth metals)
Some p-Block Elements
Organic Chemistry- Some Basic Principles and Techniques
Hydrocarbons
Environmental Chemistry
Solid State
Solutions
Electrochemistry
Chemical Kinetics
Surface Chemistry
General Principles and Processes of Isolation of Elements
p-Block Elements
d and f Block Elements
Coordination Compounds
Haloalkanes and Haloarenes
Alcohols, Phenols and Ethers
Aldehydes, Ketones and Carboxylic Acids
Organic Compounds Containing Nitrogen
Amines
Biomolecules
Polymers
Chemistry in Everyday Life
Thermodynamics
Chemistry

Maths

Sets, Relations and Functions
Algebra
Permutations and Combinations
Coordinate Geometry
Circle and System of Circles
Calculus
Mathematical Reasoning
Statistics and Probability
Properties of Triangle
Vectors and Three-Dimensional Geometry
Linear Programming
Matrices and Determinants
Trigonometric Ratios & Identities
Mathematics

Q 1.

Correct4

Incorrect-1

In short wave communication waves of which of the following frequencies will be reflected back by the ionospheric layer, having electron density 10 'per {tex} m {/tex}

{tex} 2 \,M H z {/tex}

10 {tex} M H z {/tex}

{tex} 12 \,{ MHz } {/tex}

{tex} 18 \,{ MHz } {/tex}

Q 2.

Correct4

Incorrect-1

In an amplitude modulated wave for audio frequency of 500 cycle/second, the appropriate carrier frequency will be

50 cycles/sec

100 cycles/sec

500 cycles/sec

50,000 cycles/sec

Q 3.

Correct4

Incorrect-1

AM is used for broadcasting because

It is more noise immune than other modulation systems

It requires less transmitting power compared with other systems

Its use avoids receiver complexity

No other modulation system can provide the necessary bandwidth faithful transmission

Q 4.

Correct4

Incorrect-1

Range of frequencies allotted for commercial FM radio broadcast is

{tex} \mathrm {88 \,\,to\,\, 108 }\,\,\ MHz {/tex}

{tex} \mathrm {88 \,\,to\,\, 108 }\,\,\ KHz {/tex}

{tex} \mathrm {8 \,\,to\,\, 88 }\,\,\ MHz {/tex}

{tex} \mathrm {88 \,\,to\,\, 108 }\,\,\ GHz {/tex}

Q 5.

Correct4

Incorrect-1

The velocity factor of a transmission line {tex} x {/tex}. If dielectric constant of the medium is {tex} 2.6 , {/tex} the value of {tex} x {/tex} is

0.26

0.62

2.6

6.2

Q 6.

Correct4

Incorrect-1

The process of superimposing signal frequency (i.e. audio wave) on

the carrier wave is known as

Transmission

Reception

Modulation

Detection

Q 7.

Correct4

Incorrect-1

Long distance short-wave radio broadcasting uses

Ground wave

lonospheric wave

Direct wave

Sky wave

Q 8.

Correct4

Incorrect-1

A step index fibre has a relative refractive index of {tex} 0.88 \% . {/tex} What is the critical angle at the corecladding interface

{tex} 60 ^ { \circ } {/tex}

{tex} 75 ^ { \circ } {/tex}

{tex} 45 ^ { \circ } {/tex}

None of these

Q 9.

Correct4

Incorrect-1

The characteristic impedance of a coaxial cable is of the order of

{tex} {50 \,\Omega} {/tex}

{tex} {200 \,\Omega} {/tex}

{tex} {270\, \Omega} {/tex}

None of these

Q 10.

Correct4

Incorrect-1

In which frequency range, space waves are normally propagated

{tex} \mathrm { HF } {/tex}

{tex} \mathrm { VHF } {/tex}

{tex} \mathrm {UHF} {/tex}

{tex} \mathrm { SHF } {/tex}

Q 11.

Correct4

Incorrect-1

If {tex} \mu {/tex} and {tex} \mu_{1}{/tex} are the refractive indices of the materials of core and cladding of an optical fibre, then the loss of light due to its leakage

can be minimised by having

{tex} \mu > \mu_{1} {/tex}

{tex} \mu < \mu_{1} {/tex}

{tex} \mu = \mu_{1} {/tex}

None of these

Q 12.

Correct4

Incorrect-1

Through which mode of propagation, the radio waves can be sent

from one place to another

Ground wave propagation

Sky wave propagation

Space wave propagation

All of them

Q 13.

Correct4

Incorrect-1

A laser beam of pulse power 10 watt is focussed on an object are 10 cm. The energy flux in wattl {tex} c m {/tex} at the point of focus is

10{tex}^{20}{/tex}

10{tex}^{16}{/tex}

10{tex}^{8}{/tex}

10{tex}^{4}{/tex}

Q 14.

Correct4

Incorrect-1

The carrier frequency generated by a tank circuit containing 1 {tex} n F {/tex} capacitor and {tex} 10 \mu H {/tex} inductor is

{tex} 1592 \mathrm{ Hz } {/tex}

{tex} 1592 \mathrm { MHz } {/tex}

{tex} 1592 \mathrm { kHz } {/tex}

{tex} 159.2 \mathrm { Hz } {/tex}

Q 15.

Correct4

Incorrect-1

Broadcasting antennas are generally

Omnidirectional type

Vertical type

Horizontal type

None of these

Q 16.

Correct4

Incorrect-1

For television broadcasting, the frequency employed is normally

{tex} 30 - 300\, M H z {/tex}

{tex} 30 - 300\, G H z {/tex}

{tex} 30 - 300 \,K H z {/tex}

{tex} 30 - 300 \,H z {/tex}

Q 17.

Correct4

Incorrect-1

The radio waves of frequency {tex} 300 \mathrm{ MHz } {/tex} to {tex} 3000 \mathrm{ MHz } {/tex} belong to

High frequency band

Very high frequency band

Ultra high frequency band

Super high frequency band

Q 18.

Correct4

Incorrect-1

An antenna behaves as resonant circuit only when its length is

{tex} \frac { \lambda } { 2 } {/tex}

{tex} \frac { \lambda } { 4 } {/tex}

{tex} \lambda {/tex}

{tex} \frac { \lambda } { 2 } {/tex} or integral multiple of {tex} \frac { \lambda } { 2 } {/tex}

Q 19.

Correct4

Incorrect-1

Maximum useable frequency (MUF) in F region layer is {tex} x , {/tex} when the critical frequency is {tex} 60 \mathrm { MHz } {/tex} and the angle of incidence is {tex} 70 ^ { \circ } . {/tex} Then {tex} x {/tex} is

{tex} 150 \mathrm { MHz } {/tex}

{tex} 170 \mathrm{ MHz} {/tex}

{tex} 175 \mathrm { MHz } {/tex}

{tex} 190\mathrm { MHz } {/tex}

Q 20.

Correct4

Incorrect-1

The electromagnetic waves of frequency {tex} 2 \mathrm{ MHz } {/tex} to {tex} 30 \mathrm { MHz } {/tex} are

In ground wave propagation

In sky wave propagation

In microwave propagation

In Satellite communication

Q 21.

Correct4

Incorrect-1

A laser is a coherent source because it contains

Many wavelengths

Uncoordinated wave of a particular wavelength

Coordinated wave of many wavelengths

Coordinated waves of a particular wavelength

Q 22.

Correct4

Incorrect-1

The attenuation in optical fibre is mainly due to

Absorption

Scattering

Neither absorption nor scattering

Both (a) and (b)

Q 23.

Correct4

Incorrect-1

The maximum distance upto which TV transmission from a TV tower of height {tex} h {/tex} can be received is proportional to

h{tex}^{1/2}{/tex}

h{tex}^{2}{/tex}

h{tex}^{6}{/tex}

h{tex} {/tex}

Q 24.

Correct4

Incorrect-1

A laser beam is used for carrying out surgery because it

Is highly monochromatic

Is highly coherent

Is highly directional

Can be sharply focussed

Q 25.

Correct4

Incorrect-1

Laser beams are used to measure long distances because

They are monochromatic

They are highly polarised

They are coherent

They have high degree of parallelism

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