Electronics and Communication Engineering - Exam Questions Papers

6.
The maximum percent overshoot with maximum value of first overshoot as 3.5 V and steady state value as 2.575 V is
35.92%
26.43%
57.61%
15.24%
Answer: Option
Explanation:

From the transient response characteristics, Maximum percentage overshoot (MPO) is given as

MPO decides the relative stability of the system.


7.
Find Vo(t) for the following circuit.
Data: L = 1 H, C = 1 F, R1 = R2 = 1 Ω and zero initial conditions.
0 V
5 V
3 V
2 V
Answer: Option
Explanation:

E(s) = L[e(t)] = L[5 sin 3t]

Let V1(s) = Voltage across L

and

V2(s) = Voltage across R2

V(s) = V1(s) - V2(s)


8.
An XOR gate with 8 variable is as follows:
A ⊕ B ⊕ C ⊕ D ⊕ E ⊕ F ⊕ G ⊕ H
The number of minterms in the Boolean expression is
255
127
128
256
Answer: Option
Explanation:

.


9.
The figure shown below is designed to act as a constant current source across the load resistor. The β of transistor is 50. What is the value of load current?
1.96 mA
2 mA
2.04 mA
None
Answer: Option
Explanation:

Voltage at base = 12 - 5 = 7 v

Voltage at emitter = 7 + 0.7 = 7.7 v

Current through R1 = 2 mA

Thus current through load = = 1.96 mA.


10.
For a given magnetic material operating in linear mode B = 0.06 T. Assume permeability = 51, then magnetization is:
44836 A/m
46834 A/m
946 A/m
936 A/m
Answer: Option
Explanation:

μ = λmH,

λm = (μ - 1) = 51 - 1 = 50

μ = 50 x H 46834.