Q2.Two D flip-flops are connected as a synchronous counter that goes through the
following QBQA sequence 00⟶11⟶01⟶10⟶00⟶… The combination to the inputs DA and DB are
Answer : Option DExplaination / Solution:
The sequence is QBQA
Q3.In the circuit shown below, the value of RL such that the power transferred to RL is maximum is
Answer : Option CExplaination / Solution:
Power transferred to RL will be maximum when RL is equal to the thevenin
resistance. We determine thevenin resistance by killing all source as follows :
Q4.An 8085 assembly language program is given below. Assume that the carry
flag is initially unset. The content of the accumulator after the execution of the
program is
Answer : Option CExplaination / Solution:
Initially Carry Flag, C = 0
MVI A, 07 H ; A = 0000 0111
RLC ; Rotate left without carry. A = 00001110
MVO B, A ; B = A = 00001110
RLC ; A = 00011100
RLC ; A = 00111000
ADD B ; A = 00111000
; +00001110
; 01000110
RRC ; Rotate Right with out carry, A = 0010 0011
Thus A = 23 H
Q6.The first six points of the 8-point DFT of a real valued sequence are 5, 1 - j3, 0, 3 - 4j, 0 and 3 + 4j .....The last two points of the DFT are respectively
Answer : Option BExplaination / Solution:
For 8 point DFT, and it is conjugate
symmetric about x[4], x[6] = 0; x[7] = 1 + j3
Q7.In the circuit shown below, the initial charge on the capacitor is 2.5 mC, with
the voltage polarity as indicated. The switch is closed at time t = 0. The current i(t) at a time t after the switch is closed is
Answer : Option AExplaination / Solution:
Here we take the current flow direction as positive.
Q8.An analog signal is band-limited to 4 kHz, sampled at the Nyquist rate and the samples are quantized into 4 levels. The quantized levels are assumed to be independent and equally probable. If we transmit two quantized samples per second, the information rate is ________ bits / second.
Answer : Option DExplaination / Solution:
Quantized 4 level require 2 bit representation i.e. for one sample 2 bit are required. Since 2 sample per second are transmitted we require 4 bit to be transmitted per second.
Q9.The root locus plot for a system is given below. The open loop transfer function
corresponding to this plot is given by
Answer : Option BExplaination / Solution:
For given plot root locus exists from -3 to ∞, So there must be odd number of
poles and zeros. There is a double pole at s = - 3