# Electronics and Communication Engineering - Exam Questions Papers

6.
The transfer function of a closed loop system is
where K is the forward path gain. The root locus plot of the system is :
Explanation:
No answer description is available. Let's discuss.

7.
Consider the following statements, regarding an OP AMP:
1. All types of negative feedback reduce non-linear distortion.
2. All types of negative feedback reduce the output offset voltage.
3. Non-inverting (current and voltage) feedback increases the input impedance.
4. Inverting (current and voltage) feedback decreases input impedance.
Which of the above statements is/are correct?
1 only
2 and 3 only
2 and 4 only
1, 2, 3 and 4
Explanation:
No answer description is available. Let's discuss.

8.
Which one of the following is applicable to any network-linear or non-linear, active or passive, time-varying or invariant - as long as Kirchhoff laws are not violated?
Tellegen's theorem
Reciprocity theorem
Maximum power transfer theorem
Superposition theorem
Explanation:
No answer description is available. Let's discuss.

9.
The input and output of a continuous time system are respectively denoted by x(t) and y(t) Which of the following descriptions corresponds to a causal system?
y(t) = x(t - 2) + x(t + 4)
y(t) = x(t - 4) + x(t + 1)
y(t) = x(t + 4) + x(t - 1)
y(t) = x(t + 5) + x(t + 5)