Electrical Engineering - Online Test

Q1. A 3-phase transformer rated for 33 kV/11 kV is connected in delta/star as shown in figure. The current transformers (CTs) on low and high voltage sides have a ratio of 500/5. Find the currents i1 and i2, if the fault current is 300A as shown in figure.
 
Answer : Option A
Explaination / Solution:




Q2. A function y(t), such that y(0) = 1 and y(1) = 3e-1, is a solution of the differential equation  Then y(2) is
Answer : Option B
Explaination / Solution:




Q3. In a constant V/f induction motor drive, the slip at the maximum torque
Answer : Option C
Explaination / Solution:



Q4. The Boolean expression  simplifies to
Answer : Option A
Explaination / Solution:



Q5. One end of a loss-less transmission line having the characteristic impedance of 75Ω and length of 1 cm is short-circuited. At 3 GHz, the input impedance at the other end of transmission line is
Answer : Option D
Explaination / Solution:



Q6. The full form of the abbreviations TTL and CMOS in reference to logic families are
Answer : Option C
Explaination / Solution:

TTL -> Transistor - Transistor logic CMOS -> Complementary Metal Oxide Semi-conductor

Q7.
In the following transistor circuit,  , and 𝛽 and all the capacitances are very large

The mid-band voltage gain of the amplifier is approximately
Answer : Option D
Explaination / Solution:

The small signal model is shown in fig below


Q8.
The power electronic converter shown in the figure has a single-pole double-throw switch. The pole P of the switch is connected alternately to throws A and B. The converter shown is a _______

Answer : Option A
Explaination / Solution:
No Explaination.


Q9. In the circuit shown below, the knee current of the ideal Zener diode is 10 mA. To maintain 5 V across RL, the minimum value of RL in Ω and the minimum power rating of the Zener diode in mW respectively are

Answer : Option B
Explaination / Solution:
No Explaination.


Q10. What is the Boolean expression for the output f of the combinational logic circuit of NOR gates given below?

Answer : Option B
Explaination / Solution:
No Explaination.