1
COMEDK 2025 Evening Shift
MCQ (Single Correct Answer)
+1
-0
A power transmission line feeds input power at 2200 V to a step-down transformer with its primary windings having 2000 turns. The output power is delivered at 220 V by the transformer. If the current in the primary of the transformer is 2 A and its efficiency is $80 \%$, the output current would be:
A
32 A
B
8 A
C
16 A
D
4 A
2
COMEDK 2025 Evening Shift
MCQ (Single Correct Answer)
+1
-0
A series LCR circuit having $\mathrm{R}=44 \Omega, \mathrm{~L}=2 \mathrm{H}$ and $\mathrm{C}=25 \mu \mathrm{~F}$ is connected to a variable frequency of 220 V . What is the average power transferred to the circuit in one complete cycle if the frequency of supply equals the natural frequency of the circuit?
A
2.1 kW
B
4.2 kW
C
1.1 kW
D
1.2 kW
3
COMEDK 2025 Evening Shift
MCQ (Single Correct Answer)
+1
-0
In a pure inductive circuit, a sinusoidal voltage $V(t)=200 \sin 250 t$ is applied to a pure inductance of $\mathrm{L}=0.02 \mathrm{H}$. The current through the coil is:
A
$40 \sin \left[250 t-\frac{\pi}{2}\right]$
B
$40 \cos \left[250 t-\frac{\pi}{2}\right]$
C
$40 \sin \left[250 t+\frac{\pi}{2}\right]$
D
$40 \cos \left[250 t+\frac{\pi}{2}\right]$
4
COMEDK 2025 Evening Shift
MCQ (Single Correct Answer)
+1
-0
The instantaneous values of alternating current and voltages in a circuit are $\mathrm{I}=\frac{3}{\sqrt{2}} \sin (200 \pi t)$ ampere and $\mathrm{V}=\frac{3}{\sqrt{2}} \sin \left(200 \pi t+\frac{\pi}{6}\right)$ volt. What is the average power consumed in the circuit in watt ?
A
$\frac{\sqrt{3}}{8}$
B
$\frac{6 \sqrt{3}}{8}$
C
$\frac{8 \sqrt{2}}{9}$
D
$\frac{9 \sqrt{3}}{8}$
COMEDK Subjects
EXAM MAP