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 ?

Related Mcqs:

1. 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

2. A 5 mA changes in Zener current produces a 50 mA change in Zener voltage. What is the Zener impedance ?

   A. 1 O
   B. 1 O
   C. 100 O
   D. 10 O

3. For increasing the voltage rating, zeners are connected in_____________?

   A. Parallel
   B. Series-parallel
   C. Series
   D. None of the above

4. If the input a.c. voltage to regulated or ordinary power supply increases by 5% what will be the approximate change in d.c. output voltage?

   A. 10%
   B. 20%
   C. 15%
   D. 5%

5. 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

6. A power supply can deliver a maximum rated current of 0.5 A at full-load output voltage of 20 V. What is the minimum load resistance that you can connect across the supply?

   A. 10 O
   B. 20 O
   C. 15 O
   D. 40 O

7. 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

8. In an unregulated power supply, if input a.c. voltage increases, the output voltage _______________?

   A. Increases
   B. Decreases
   C. Remains the same
   D. None of the above

9. An ideal regulated power supply is one which has voltage regulation of________________?

   A. 0%
   B. 5%
   C. 10%
   D. 1%

10. A power supply has a voltage regulation of 1%. If the no-load voltage is 20 V, what is the full-load voltage ?

    A. 8 V
    B. 7 V
    C. 6 V
    D. 2 V