# Electronics and Communication Engineering - Exam Questions Papers

11.
A system with transfer function has an output for the input signal . Then, the system parameter 'p' is
3
1
Explanation:

|y(t)| = |M(ω)||x(t)|.

ω2 + p2 = ω2p2, 4 + p2 = 4p2

3p2 = 4, .

12.
The current i(t), though a 10 Ω resistor in series with an inductance, is given by i(t) = 3 + 4 sin (10t + 45°) + 4 sin (300t + 60°) Amperes. The RMS value of the current and the power dissipated in the circuit are
41 A, 410 W, respectively
35 A, 350 W, respectively
5 A, 250 W, respectively
11 A, 1210 W, respectively
Explanation:

Irms = = 6.4

Power P = I2R = 25 x 10 = 41 x 10 = 410 W.

13.
The differential equation for the current i(t) in the circuit of figure is
Explanation:

Apply KVL to the loop

Differentiate w.r.t. t

.

14.
A transmitter radiates a power 20 KW and its base current is 18A. The radiation resistance of the antenna is
1111 Ω
900 Ω
75 Ω
62 Ω
Explanation:

.

15.
e-2t is __________ .
energy signal
power signal
neither energy signal nor power signal
both energy and power signal