Bissoy
Login
Get Advice on Live Video Call
Earn $ Cash $ with
consultations on Bissoy App
When the input and output power in an optical fiber is 120μW & 3μW respectively and the length of the fiber is 8 km. What is the signal attenuation per km for the fiber?
A
3dB/km
B
2dB/km
C
1dB/km
D
4dB/km
Correct Answer:
2dB/km
Consider the 5 × 5 matrix \[{\text{A}} = \left[ {\begin{array}{*{20}{c}} 1&2&3&4&5 \\ 5&1&2&3&4 \\ 4&5&1&2&3 \\ 3&4&5&1&2 \\ 2&3&4&5&1 \end{array}} \right
A
\
B
<br>It is given that A has only one real eigen value.<br>Then the real eigen value of A is
C
<p><span>A.</span> -2.5
D
</span> 0
When the input and output power in an optical fiber is 120μW & 3μW respectively and the length of the fiber is 8 km. What is the signal attenuation per km for the fiber?
A
3dB/km
B
2dB/km
C
1dB/km
D
4dB/km
Let A be an m × n matrix and Ban n × m matrix. It is given that determinant ($$I$$
m
+ AB) = determinant ($$I$$
n
+ BA), where $$I$$
k
is the k × k identity matrix. Using the above property, the determinant of the matrix given below is
\[\left[ {\begin{array}{*{20}{c}} 2&1&1&1 \\ 1&2&1&1 \\ 1&1&2&1 \\ 1&1&1&2 \end{array}} \right
A
\
B
<p><span>A.</span> 2
C
</span> 5
Eigen values of the matrix \[\left[ {\begin{array}{*{20}{c}} 0&1&0&0 \\ 1&0&0&0 \\ 0&0&0&{ - 2i} \\ 0&0&{2i}&0 \end{array}} \right
A
\
B
are
C
<p><span>A.</span> -2, -1, 1, 2
D
</span> -1, 1, 0, 2
Determine the attenuation per kilometer for a fiber whose length is 2 km, output voltage is 2.1 V at a wavelength of 0.85μm. The output voltage increases to 10.7 V when the fiber is cut-back to leave 2 metres. Determine the attenuation per km for the fiber at wavelength 0.85μm.
A
2.8dB/km
B
3.1dB/km
C
3.5dB/km
D
8dB/km
If the input power 100μW is launched into 6 km of fiber, the mean optical power at the fiber output is 2μW. What is the overall signal attenuation through the fiber assuming there are no connectors or splices?
A
15.23dB
B
16.98dB
C
17.12dB
D
16.62dB
Consider a system whose input r and output y are related by the equation $$y\left( t \right) = \int\limits_{ - \infty }^\infty {x\left( {t - \tau } \right)} h\left( {2\tau } \right)d\tau $$
Where h(t) is shown in the graph
Which of the following four properties are possessed by the system? BIBO: Bounded input gives a bounded output
Causal: The system is causal.
LP : The system is low pass.
LTI: The system is linear and time-invariant.
A
Causal, LP
B
BIBO, LTI
C
BIBO, Causal, LTI
D
LP, LTI
A single-mode optical fiber has an attenuation of 0.3dB/km when operating at wavelength of 1.1μm. The fiber core diameter is 4μm and bandwidth is 500 MHz. Find threshold optical power for stimulated Brillouin scattering.
A
11.20 mw
B
12.77 mw
C
13.08 mw
D
12.12 mw
________ couplers combine the different wavelength optical signal onto the fiber or separate the different wavelength optical signal output from the fiber.
A
3-port
B
2*2-star
C
WDM
D
Directional
A planar LED is fabricated from GaAs is having a optical power emitted is 0.018% of optical power generated internally which is 0.018% of optical power generated internally which is 0.6 P. Determine external power efficiency.
A
0.18%
B
0.32%
C
0.65%
D
0.9%