Electronics Engineering - Online Test
Q1. Which of the following is an invalid state in an 8-4-2-1. Binary Coded Decimal counter
Answer : Option D
Explaination / Solution:
In binary coded decimal (BCD) counter the valid states are from 0 to 9 only in binary system 0000 to 1001 only. So, 1100 in decimal it is 12 which is invalid state in BCD counter.
Q2. Match the following:
Instrument Type Used for
P. Permanent magnet moving coil 1. DC only
Q. Moving iron connected through current transformer 2. AC only
R. Rectifier 3.AC and DC
S. Electrodynamometer
Answer : Option C
Explaination / Solution:
No Explaination.
Q3. The parallel branches of a 2-wire transmission line re terminated in 100Ω and
200Ω resistors as shown in the figure. The characteristic impedance of the
line is Z0 = Ω and each section has a length of λ/4. The voltage reflection
coefficient Γ at the input is
Answer : Option D
Explaination / Solution:
Q4. In the following limiter circuit, an input voltage Vi = 10 sin100πt is applied.
Assume that the diode drop is 0.7 V when it is forward biased. When it is
forward biased. The zener breakdown voltage is 6.8 V
The maximum and minimum values of the output voltage respectively are
Answer : Option C
Explaination / Solution:
No Explaination.
Q5. In the following figure, C1 and C2 are ideal capacitors. C1 has been charged to 12 V before the ideal
switch S is closed at t = 0. The current i(t) for all t is
Answer : Option D
Explaination / Solution:
Time constant = RC
In the given circuit, R = 0
Rise time = 0; hence capacitor charges instantaneously and the current can be represented as impulse function
Q6. Consider an electron, a neutron and a proton initially at rest and placed along a straight line such that the neutron is exactly at the center of the line joining the electron and proton. At t=0, the particles are released but are constrained to move along the same straight line. Which of these will collide first?
Answer : Option D
Explaination / Solution:
Q7. The transfer function of a compensator is given as
The phase of the above lead compensator is maximum at
Answer : Option A
Explaination / Solution:
Q8. For a periodic signal 
the
fundamental frequency in radians/s is
the
fundamental frequency in radians/s is
Answer : Option A
Explaination / Solution:
No Explaination.
Q9. Given that the op-amp is ideal, the output voltage V0 is
Answer : Option B
Explaination / Solution:
No Explaination.
Q10. Consider the set of strings on {0,1} in which, every substring of 3 symbols has at most two
zeros. For example, 001110 and 011001 are in the language, but 100010 is not. All strings of
length less than 3 are also in the language. A partially completed DFA that accepts this
language is shown below.
The missing arcs in the DFA are
Answer : Option D
Explaination / Solution:
The complete DFA is
