Electronics Engineering - Online Test
Q1. The Voltage Source Inverter (VSI) shown in the figure below is switched to provide a 50 Hz, square-wave
ac output voltage (v0) across an R-L load. Reference polarity of v0 and reference direction of the output
current i0 are indicated in the figure. It is given that R = 3 Ω, L = 9.55 mH.
In the interval when v0 < 0 and i0 > 0 the pair of devices which conducts the load current is
Answer : Option D
Explaination / Solution:
No Explaination.
Q2. What is the minimal form of the Karnaugh map shown below? Assume that X denotes a don’t
care term.
Answer : Option B
Explaination / Solution:
Q3. The nature of feedback in the op-amp circuit shown is
Answer : Option B
Explaination / Solution:
No Explaination.
Q4. The SOP (sum of products) form of a Boolean function is Σ(0,1,3,7,11), where inputs are A,B,C,D (A is MSB, and D is LSB). The equivalent minimized expression of the function is
Answer : Option A
Explaination / Solution:
Q5. A right circularly polarized (RCP) plane wave is incident at an angle 600 to the
normal, on an air-dielectric interface. If the reflected wave is linearly polarized,
the relative dielectric constant ξr is.
Answer : Option D
Explaination / Solution:
No Explaination.
Q6. The drain current of MOSFET in saturation is given by 
where K is a constant.
where K is a constant. The magnitude of the transconductance gm is
Answer : Option B
Explaination / Solution:
Q7. The slope and level detector circuit in a CRO has a delay of 100 ns. The start-stop sweep generator has a response time of 50 ns. In order to display correctly, a delay line of
Answer : Option A
Explaination / Solution:
The delay line should be inverted in VDP (Y-channel) only.
Q8. 
With 10 V dc connected at port A in the linear nonreciprocal two-port network shown below, the following were observed:
(i) 1Ω connected at port B draws a current of 3 A
(ii) 2.5Ω W connected at port B draws a current of 2 A
For the same network, with 6 V dc connected at port A, 1Ω connected at port B draws 7/3 A.
If 8 V dc is connected to port A, the open circuit voltage at port B is
Answer : Option B
Explaination / Solution:
No Explaination.
Q9. Divergence of the three-dimensional radial vector field 
is
is
Answer : Option A
Explaination / Solution:
No Explaination.
Q10. 
In the feedback network shown below, if the feedback factor k is increased, then the
Answer : Option A
Explaination / Solution:
No Explaination.
