Electronics and Communication Engineering - Exam Questions Papers

Exercise :: Exam Questions Papers - Exam Paper 21
11.
Efficiency of general AM signal with e_{m} = E_{1} cos ω_{1} t + E_{2} cos ω_{2} t with modulation index m _{1} and m _{2} is __________ .

Answer: Option B

Explanation:

12.
Poynting vector is associated with

A.
flux in magnetic field B.
power flow in electrostatic field C.
current in electrostatic field D.
charge in electrostatic field

Answer: Option B

Explanation:

13.
A random process x(t) is defined by x(t) = 2 cos (2p t + Y) where Y is a discrete random variable with P(Y = 0) = and Then R_{xx} (0, 1) =

Answer: Option D

Explanation:

14.
Consider points P and Q in the x-y plane, with P = (1, 0) and Q = (0, 1). The line integral 2 (xdx + ydy ) along the semicircle with the line segment PQ as its diameter

A.
is - 1 B.
is 0 C.
is 1 D.
depends on the direction (clockwise or anti-clockwise) of the semicircle

Answer: Option B

Explanation:

15.
What are the counting stages (Q_{1} , Q_{2} ) for the counter shown in the figure below?

A.
11, 10, 00, 11, 10, ... B.
01, 10, 11, 00, 10, ... C.
00, 11, 01, 10, 00, ... D.
01, 10, 00, 01, 10, ...

Answer: Option A

Explanation: