Electromagnetism
Current Electricity
MCQ (Single Correct Answer)
Moving Charges and Magnetism
MCQ (Single Correct Answer)
Magnetism and Matter
MCQ (Single Correct Answer)
Electromagnetic Induction
MCQ (Single Correct Answer)
Alternating Current
MCQ (Single Correct Answer)
Electromagnetic Waves
MCQ (Single Correct Answer)
Modern Physics
Dual Nature of Radiation
MCQ (Single Correct Answer)
Semiconductor Devices and Logic Gates
MCQ (Single Correct Answer)
Communication Systems
MCQ (Single Correct Answer)
1
COMEDK 2023 Morning Shift
MCQ (Single Correct Answer)
+1
-0

In an electrical circuit $$R, L, C$$ and $$\mathrm{AC}$$ voltage source are all connected in series. When $$L$$ is removed from the circuit, the phase difference between the voltage and the current in the circuit is $$\pi / 3$$. If instead $$C$$ is removed from the circuit, the phase difference is again $$\pi / 3$$. The power factor of the circuit is

A
$$1 / 2$$
B
$$1 \sqrt{2}$$
C
1
D
$$\frac{\sqrt{3}}{2}$$
2
COMEDK 2023 Evening Shift
MCQ (Single Correct Answer)
+1
-0

$$220 \mathrm{~V}$$ ac is more dangerous than $$220 \mathrm{~V}$$ dc Why?

A
The peak value of ac is greater than the given value of dc
B
Shock received from ac is always repulsive
C
The frequency of ac is more than that of dc
D
The speed of ac is more than that of $$\mathrm{dc}$$
3
COMEDK 2023 Evening Shift
MCQ (Single Correct Answer)
+1
-0

What should be the inductance of an inductor connected to $$200 \mathrm{~V}, 50 \mathrm{~Hz}$$ source so that the maximum current of $$\sqrt{2}$$ A flows through it?

A
$$\frac{\sqrt{2}}{\pi} H$$
B
$$2 \pi H$$
C
$$\frac{2}{\pi} \mathrm{H}$$
D
$$\frac{\pi}{2} H$$
4
COMEDK 2022
MCQ (Single Correct Answer)
+1
-0

During the phenomenon of resonance

A
the amplitude of oscillation becomes large
B
the frequency of oscillation becomes large
C
the time period of oscillation becomes large
D
All of the above
COMEDK Subjects