Explore topic-wise MCQs in Optical Communication.

This section includes 21 Mcqs, each offering curated multiple-choice questions to sharpen your Optical Communication knowledge and support exam preparation. Choose a topic below to get started.

1.

Considering the values given below, calculate the mode separation in terms of free space wavelength for a laser. (Frequency separation = 2GHz, Wavelength = 0.5 μm)

A. 1.4×10-11
B. 1.6×10-12
C. 1×10-12
D. 6×10-11
Answer» C. 1×10-12
2.

An injection laser has active cavity losses of 25 cm-1 and the reflectivity of each laser facet is 30%. Determine the laser gain coefficient for the cavity it has a length of 500μm.

A. 46 cm-1
B. 51 cm-1
C. 50 cm-1
D. 49.07 cm-1
Answer» E.
3.

A ruby laser has a crystal of length 3 cm with a refractive index of 1.60, wavelength 0.43 μm. Determine the number of longitudinal modes.

A. 1×102
B. 3×106
C. 2.9×105
D. 2.2×105
Answer» E.
4.

__________________ in the laser occurs when photon colliding with an excited atom causes the stimulated emission of a second photon.

A. Light amplification
B. Attenuation
C. Dispersion
D. Population inversion
Answer» B. Attenuation
5.

An incandescent lamp is operating at a temperature of 1000K at an operating frequency of 5.2×1014 Hz. Calculate the ratio of stimulated emission rate to spontaneous emission rate.

A. 3×10-13
B. 1.47×10-11
C. 2×10-12
D. 1.5×10-13
Answer» C. 2×10-12
6.

The frequency of the absorbed or emitted radiation is related to difference in energy E between the higher energy state E2 and the lower energy state E1. State what h stands for in the given equation?

A. Gravitation constant
B. Planck’s constant
C. Permittivity
D. Attenuation constantView Answer
Answer» C. Permittivity
7.

A device which converts electrical energy in the form of a current into optical energy is called as ___________

A. Optical source
B. Optical coupler
C. Optical isolator
D. Circulator
Answer» B. Optical coupler
8.

A_RUBY_LASER_HAS_A_CRYSTAL_OF_LENGTH_3_CM_WITH_A_REFRACTIVE_INDEX_OF_1.60,_WAVELENGTH_0.43_‚ÂÀ√≠¬¨‚À´M._DETERMINE_THE_NUMBER_OF_LONGITUDINAL_MODES.?$#

A. 1√ó10<sup>2 </sup>
B. 3√ó10<sup>6 </sup>
C. 2.9√ó10<sup>5 </sup>
D. 2.2√ó10<sup>5 </sup>
Answer» E.
9.

Doppler broadening is a homogeneous broadening mechanism. State whether the given statement is true or false.$

A. True
B. False
Answer» C.
10.

A_semiconductor_laser_crystal_of_length_5_cm,_refractive_index_1.8_is_used_as_an_optical_source._Determine_the_frequency_separation_of_the_modes.$

A. 2.8 GHz
B. 1.2 GHz
C. 1.6 GHz
D. 2 GHz
Answer» D. 2 GHz
11.

Considering the values given below, calculate the mode separation in terms of free space wavelength for a laser.

A.
B.
Answer» C.
12.

Longitudinal modes contribute only a single spot of light to the laser output. State whether the given statement is true or false.

A. True
B. False
Answer» B. False
13.

An_injection_laser_has_active_cavity_losses_of_25_cm-1and_the_reflectivity_of_each_laser_facet_is_30%._Determine_the_laser_gain_coefficient_for_the_cavity_it_has_a_length_of_500μm.$

A. 46 cm<sup>-1</sup>
B. 51 cm<sup>-1</sup>
C. 50 cm<sup>-1</sup>
D. 49.07 cm<sup>-1</sup>
Answer» E.
14.

__________________ in the laser occurs when photon colliding with an excited atom causes the stimulated emission of a second photon?

A. Light amplification
B. Attenuation
C. Dispersion
D. Population inversion
Answer» B. Attenuation
15.

The lower energy level contains more atoms than upper level under the conditions of ________________

A. Isothermal packaging
B. Population inversion
C. Thermal equilibrium
D. Pumping
Answer» D. Pumping
16.

An incandescent lamp is operating at a temperature of 1000K at an operating frequency of 5.2√ó1014 Hz. Calculate the ratio of stimulated emission rate to spontaneous emission rate.$

A. 3√ó10<sup>-13 </sup>
B. 1.47√ó10<sup>-11 </sup>
C. 2√ó10<sup>-12 </sup>
D. 1.5√ó10<sup>-13 </sup>
Answer» C. 2‚Äö√†√∂‚àö‚â•10<sup>-12 </sup>
17.

Which process gives the laser its special properties as an optical source?

A. Dispersion
B. Stimulated absorption
C. Spontaneous emission
D. Stimulated emission
Answer» E.
18.

The radiation emission process (emission of a proton at frequency) can occur in __________ ways.

A. Two
B. Three
C. Four
D. One
Answer» B. Three
19.

The frequency of the absorbed or emitted radiation is related to difference in energy E between the higher energy state E2 and the lower energy state E1. State what h stands for in the given equation?

A.
B. Gravitation constant
C. Planck’s constant
Answer» C. Planck‚Äö√Ñ√∂‚àö√ë‚àö¬•s constant
20.

How many types of sources of optical light are available?

A. One
B. Two
C. Three
D. Four
Answer» D. Four
21.

A device which converts electrical energy in the form of a current into optical energy is called as

A. Optical source
B. Optical coupler
C. Optical isolator
D. Circulator
Answer» B. Optical coupler