# ECE - Questions and solutions set-2

Electronics and communication Engineering Questions and solutions set-2.

Question:-
Option (A)
(2,1,1,1)
Option (B)
(1,-1,-1,2)
Option (C)
(1,1,1,2)
Option (D)
(2,-1,-1,1)
Correct Option:
B
Question Solution:
Y11 = 2,Y12 = 1,Y21 = 1,Y22 = 1
ÑY = 1, Z11 =1/1 = 1,Z12 = -1/1 = -1,Z21 = - 1/1 Z22 = 2/1=2
Question:-
Option (A)
N – Type with carrier concentration of 2 × 1012/cm3
Option (B)
P-Type with carrier concentration of 1 × 1012/cm3
Option (C)
N-Type with carrier concentration of 3×1012/cm3
Option (D)
P-Type with carrier concentration of 3×1012/cm3
Correct Option:
A
Question Solution:
n+Na =Nd+p
\n=p+(3×1012–1012)
n=p+2×1012
Question:-
Option (A)
4 mm
Option (B)
2 mm
Option (C)
8 mm
Option (D)
1 mm
Correct Option:
D
Question Solution:
wa(Ö(V+V0))-1

w1/w2 =Ö{(7.2+0.8)/1.2+0.8)} = 2Þ2/w2=2

Question:-
Option (A)
64
Option (B)
100
Option (C)
128
Option (D)
512
Correct Option:
D
Question Solution:
Mp is the peak value of amplitude
Ñ=2Mp/L =(6.114/L)
But Nq=12´10-6= Ñ2/12
Question:-
Option (A)
System is neither Controllable nor Observable
Option (B)
System is Completely controllable and Observable
Option (C)
System is Observable but Uncontrollable
Option (D)
System is Controllable but Unobservable
Correct Option:
B
Question Solution:
If there are no pole zero cancellation then it will be completely controllable
and observable
Question:-
Option (A)
TE10
Option (B)
TE20
Option (C)
TE01
Option (D)
TE11
Correct Option:
A
Question Solution:
TE10 has lc = 14.4cm
TE01 has lc= 6.8 cm
TE11 has lc = 6.2 cm
TE20 has lc= 7.2 cm
Only TE10 is greater than 10 cm so only TE10 will transmit.