Explore topic-wise MCQs in Electrical Engineering.

This section includes 64 Mcqs, each offering curated multiple-choice questions to sharpen your Electrical Engineering knowledge and support exam preparation. Choose a topic below to get started.

51.

As the junction temperature increases, the voltage breakdown point for Zener mechanism ___________

A. Is increased
B. Is decreased
C. Remains the same
D. None of the above
Answer» C. Remains the same
52.

The rupture of covalent bonds will occur when the electric field is ___________

A. 100 V/cm
B. 0.6 V/cm
C. 1000 V/cm
D. More than 10⁵ V/cm
Answer» E.
53.

A 30 V Zener will have depletion layer width ___________ that of 10 V Zener

A. More than
B. Less than
C. Equal to
D. None of the above
Answer» B. Less than
54.

An ideal regulated power supply is one which has voltage regulation of ___________

A. 0%
B. 5%
C. 10%
D. 1%
Answer» B. 5%
55.

If the doping level is increased, the breakdown voltage of the Zener ___________

A. Remains the same
B. Is increased
C. Is decreased
D. None of the above
Answer» D. None of the above
56.

In a 15 V Zener diode , the breakdown mechanism will occur by ___________

A. Avalanche mechanism
B. Zener mechanism
C. Both Zener and avalanche mechanism
D. None of the above
Answer» B. Zener mechanism
57.

If the load resistance decreases in a Zener regulator, then Zener current ___________

A. Decreases
B. Stays the same
C. Increases
D. None of the above
Answer» B. Stays the same
58.

In a regulated power supply, two similar 15 V zeners are connected in series. The input voltage is 45 V d.c. If each Zener has a maximum current rating of 300 mA, what should be the value of the series resistance?

A. 10 Ω
B. 50 Ω
C. 25 Ω
D. 40 Ω
Answer» C. 25 ≈í¬©
59.

A Zener diode ___________

A. Is a battery
B. Acts like a battery in the breakdown region
C. Has a barrier potential of 1 V
D. Is forward biased
Answer» C. Has a barrier potential of 1 V
60.

If the load current drawn by unregulated power supply increases, the d.c. output voltage ___________

A. Increases
B. Decreases
C. Stays the same
D. None of the above
Answer» C. Stays the same
61.

Two similar 15 V Zeners are connected in series. What is the regulated output voltage?

A. 15 V
B. 5 V
C. 30 V
D. 45 V
Answer» D. 45 V
62.

Commercial power supplies have voltage regulation ___________

A. of 10%
B. of 15%
C. of 25%
D. within 1%
Answer» E.
63.

Which of these is the best description for a Zener diode?

A. It is a diode
B. It is a constant current device
C. It is a constant-voltage device
D. It works in the forward region
Answer» D. It works in the forward region
64.

A Zener voltage regulator will cease to act as a voltage regulator if Zener current becomes ___________

A. Less than load current
B. Zero
C. More than load current
D. None of the above
Answer» C. More than load current