Electronics and Communication Engineering - Exam Questions Papers

1. 

A ramp input applied to a unity feedback system results in 5% steady state error. The type number and zero frequency gain of the system are respectively.

A. 1 and 20
B. 0 and 20
C. 0 and 1/20
D. 1 and 1/20

Answer: Option A

Explanation:

ess = 5% ⇒ .05

.


2. 

A fair coil is tossed 10 times. What is the probability that ONLY the first two tosses will yield heads?

A.
B.
C.
D.

Answer: Option C

Explanation:

Use ncr, (p)r (q)n-r [for any two losses yield head].

But in present case it is required case it is only for first two tosses. Thus in this case 10 times.


3. 

The equation sin (z) = 10 has

A. no real or complex solution
B. exactly two distinct complex solutions
C. a unique solution
D. an infinite number of complex solutions

Answer: Option A

Explanation:

Since value lies between - 1 and + 1. Therefore no real or complex solution exists.


4. 

Given If , then the value of K is

A. 1
B. 2
C. 3
D. 4

Answer: Option D

Explanation:

.


5. 

Consider the Schmitt trigger circuit shown below. A triangular wave which goes from - 12 V to 12 V is applied to the inverting input of the op-amp. Assume that the output of the op-amp moves from +15 V to -15 V. The voltage at the non-inverting switches between

A. -12 V and +12 V
B. -7.5 V and +7.5 V
C. -5 V and +5 V
D. 0 V and 5 V

Answer: Option B

Explanation:

V0 is switching between + 15 to - 150

Thus voltage at non-inverting input switches between

, 7.5 to - 7.5 .


1 2 3 4 5 6 7 8 9 10 Next »