Electrical Engineering - Online Test
Q1. 
A separately excited DC motor runs at 1500 rpm under no-load with 200V applied to the armature. The field voltage is maintained at its rated value. The speed of the motor, when it delivers at torque of 5 Nm, is 1400 rpm as shown in the figure. The rotational losses and armature reaction are neglected.
The armature resistance of the motor is.
Answer : Option B
Explaination / Solution:
No Explaination.
Q2. In an 8085 microprocessor, the contents of the Accumulator, after the following instructions are executed will become
XRA A
MVI B, F0H
SUB B
Answer : Option D
Explaination / Solution:
Q3. A bar of Gallium Arsenide (GaAs) is doped with Silicon such that the Silicon atoms occupy Gallium and Arsenic sites in the GaAs crystal. Which one of the following statement is true?
Answer : Option A
Explaination / Solution:
Silicon atoms act as P- type dopants in Arsenic sites and n- type dopants in Gallium sites.
Q4. The correct full wave rectifier circuit is
Answer : Option C
Explaination / Solution:
Q5. RA and RB are the input resistances of circuits as shown below. The circuits extend infinitely in the
direction shown. Which one of the following statements is TRUE?
Answer : Option D
Explaination / Solution:
Q6. Let the eigenvalues of a 2 x 2 matrix A be 1, -2 with eigenvectors x1 and x2 respectively. Then the eigenvalues and eigenvectors of the matrix A2 − 3A + 4I would, respectively, be
Answer : Option A
Explaination / Solution:
Q7. The gain at the breakaway point of the root locus of a unity feedback system with open loop
transfer function 
is
is
Answer : Option A
Explaination / Solution:
Q8. 
Let a causal LTI system be characterized by the following differential equation, with initial rest condition
Where x(t) and y(t) are the input and output respectively. The impulse response of the system is (u(t) is the unit step function)
Answer : Option B
Explaination / Solution:
Q9. 
In the following network, the switch is closed at t = 0- and the sampling starts from t = 0. The sampling frequency is 10 Hz.
The samples x(n), n = (0, 1, 2, ...) are given by
Answer : Option B
Explaination / Solution:
No Explaination.
Q10. Consider two buses connected by an impedance of (0+j5) Ω. The bus1 voltage is 100∠300 V,
and bus2 voltage is 100∠00V. The real and reactive power supplied by bus 1, respectively, are
Answer : Option A
Explaination / Solution:
No Explaination.
