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

A. 35.92%
B. 26.43%
C. 57.61%
D. 15.24%

Answer: Option A

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.

A. 0 V
B. 5 V
C. 3 V
D. 2 V

Answer: Option A

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

A. 255
B. 127
C. 128
D. 256

Answer: Option C

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?

A. 1.96 mA
B. 2 mA
C. 2.04 mA
D. None

Answer: Option A

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:

A. 44836 A/m
B. 46834 A/m
C. 946 A/m
D. 936 A/m

Answer: Option B

Explanation:

μ = λmH,

λm = (μ - 1) = 51 - 1 = 50

μ = 50 x H 46834.