10 Question-answer on Junction diodes
1. The current obtained from a simple filter less rectifier is:
(a) Varying direct current
(b) Constant direct current
(c) Half current
(d) Eddy current
Ans: (a)
2. In half wave rectifier, the r.m.s value of the A.C. component of the wave is
(a) Equal to d.c. value
(b) More then d.c. value
(c) Less than d.c. value
(d) Zero
Ans: (b)
3. In the half wave rectifier circuit operating from 50 hz mains frequency, the fundamental frequency in the ripple would be
(a) 25 hz
(b) 50 hz
(c) 70.7 hz
(d) 100 hz
Ans: ( b)
4. In a full wave rectifier circuit operating from 50 hz mains frequency, the fundamental frequency in the ripple would be:
(a) 25 hz
(b) 50 hz
(c) 70.7 hz
(d) 100 hz
Ans: (d)
5. At a reverse voltage of 0-1 volt, the reverse current in a germanium diode is 100 microampere. The current at a forward bias voltage of 0.2 volt will be about
(a) 1 microampere
(b) 10 milliampere
(c) 300 milliampere
(d) 1 milliampere.
Ans: (d)
6. In V-I characteristic of a PN junction reverse biasing result in:
(a) Leakage current
(b) The current which cannot be neglected
(c) No flow of current
(d) Large current
Ans: ( a)
7. Zener diode is used for
(a) Amplification
(b) Rectification
(c) Stabilization
(d) All of the above.
Ans: ( c)
8. In a junction diode, the direction of diffusion current is
(a) From n-region to p-region
(b) From p-region to n-region
(c) From n-region to p-region if the junction is forward baised and vice versa if it is reverse biased
(d) From p-region to n-region if the junction is forward biased and vice versa if it is reversed biased.
Ans: (b)
9. P-N junction is:
(a) Ohmic resistance
(b) None ohmic resistance
(c) Negative resistance
(d) Positive resistance.
Ans: (b)
10. The reverse biasing in junction diode
(a) Decreases the potential barrier
(b) Increases the potential barrier
(c) Increases the number of majority charge carriers.
(d) Increases the number of majority charge carriers.
Ans: (b)