PN Junction Diode Quiz

1. The ripple factor for a half wave rectifier is

A. 0.5
B. 0.75
C. 1.21
D. 2.0


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C. 1.21

2. The ripple factor for a full wave rectifier is

A. 0.482
B. 0.96
C. 1
D. 1.46


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A. 0.482

3. The electrons in an atom moves in

A. circular orbits
B. hyperbolic orbits
C. elliptical orbits
D. straight lines


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C. elliptical orbits

4. The bulf resistance of a diode is the resistance of

A. P material only
B. N material only
C. P and N materials
D. the resistance of the junction alone.


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C. P and N materials

5. The forbidden energy gap is highest for

A. Silicon
B. Geranium
C. Gallium Arsenide
D. Same in all above


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C. Gallium Arsenide

6. Any semi-conducter material has valance of electrons

A. 4
B. 5
C. 6
D. 7


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A. 4

7. Depletion region in a PN junction diode is due to

A. forward biasing
B. reverse biasing
C. either forward or reverse biasing
D. an area created by doping


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B. reverse biasing

8. Maximum rectification efficiency for a half wave rectifier is

A. 25%
B. 40.6%
C. 50%
D. 66.36%


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B. 40.6%

9. Maximum rectification efficiency for a full wave rectifier is

A. 40.6%
B. 66.4%
C. 81.2%
D. 100%


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C. 81.2%

10. The depletion layer of a PN junction diode hash

A. only free mobile holes
B. only free mobile electrons
C. both free mobile holes and electrons
D. neither free mobile holes nor electrons


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D. neither free mobile holes nor electrons

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LED QUIZ

1. The material used for white LED is

A. GaAs
B. GaAsP
C. GaP
D. Blue/UV Diode with yellow phosphorus

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D. Blue/UV Diode with yellow phosphorus

2. The material used for ultraviolet LED is

A. AlN
B. AlGaN
C. AlGaInN
D. All of the above

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D. All of the above

3. LED is a type of

A. Zener Diode
B. Gunn Diode
C. Varacter Diode
D. P-N junction Diode

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D. P-N junction Diode

4. LED device spectral response is given by a graph between

A. Light output Vs wavelength
B. Light output Vs Forward Voltage (V_F)
C. Light output Vs Forward Current (I_F)
D. Light output Vs Reverse Voltage (V_R)

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D. Light output Vs Reverse Voltage (V_R)

5. The colour emitted by LED is decided by

A. Forward Current
B. Forward Voltage
C. Material used
D. wavelength of the input voltage

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C. Material used

6. The material used for Red LED is

A. GaP
B. GaAsP
C. AlGaAs
D. All of the above

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D. All of the above

7. The material used for Orange LED is

A. GaP
B. GaAsP
C. AlGaInP
D. All of the above

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D. All of the above

7. The material used for Blue LED is

A. ZnSe
B. InGaN
C. SiC
D. All of the above

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D. All of the above

9. The material used for Green LED is

A. GaN
B. GaP
C. InGaN
D. All of the above

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D. All of the above

10. Purple LED can be formed by

A. Dual blue/red LEDs
B. White with purple plastic
C. Blue with red phosphorus material
D. All of the above

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D. All of the above

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Diode and its Application Quiz

1.For a Ge- PN junction the barrier potential is ________

A. 0.7V
B. 0.3V
C. 1.2V
D. 230V

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B. 0.3V

2. Static forward resistance of a diode is given by

A. ratio of forward d.c. current to forward d.c. voltage
B. ratio of forward d.c. voltage to forward d.c. current
C. ratio of forward d.c. voltage to reverse d.c. voltage
D. ratio of forward d.c. current to reverse d.c. current

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B. ratio of forward d.c. voltage to forward d.c. current

3. Number of diode/s required for a half bridge rectifier is/are

A. 1
B. 2
C. 4
D. 3

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A. 1

4.Reverse biased characteristics of a diode can be plotted in________

A. Second quadrant
B. First quadrant
C. Third quadrant
D. Fourth quadrant

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C. Third quadrant

5.A Zener diode is generally operated for current __________

A. between I_{z  (min) and} I_{z (max)}
B. greater than  I_{z (max).}
C.less than I_{z  (min) .}
D.current does not put any limit on its operation.

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A. between I_{z  (min) and} I_{z (max)}

6. The depletion region has________________

A. very few carriers
B. large number of carriers
C. no carriers
D. uncertain

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A. very few carriers

7. The characteristics of a diode are ______________ by  the network in which it is employed.

A. altered
B. unaltered
C. sometimes changed
D. can't say

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B. unaltered

8. In a LED,___________________

A. longer leg is anode.
B. smaller leg is anode.
C. Both legs are of equal size.
D. Though the lengths are unequal it does not indicate anode or cathode.

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A. bigger leg is anode.

LED has one leg longer then the other one, the longer one is positive and the smaller one is negative. If LED has same length of legs then look inside LED for two kind of triangle pieces and one of them will be smaller which is positive and other one is  negative.

9. The circuit which convert a.c. to d.c. is called ___________

A. filter
B. rectifier
C. inverter
D. voltage regulator

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B. rectifier

10.One of the following is commonly used compound semiconductor material

A. GaAs
B. Si
C. GaN
D. SiO2

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A. GaAs
Gallium Arsenide is commonly used compound semiconductor material.

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Diode and Application Quiz

1. Reverse leakage current P-N in junction diode

A. Increases with temperature rise
B. Decreases with temperature rise
C. Depends upon current limiting resistor
D. Depends only on reverse voltage

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C. Depends upon current limiting resistor

2. The DC resistance of P-N junction diode is also called as

A. Static resistance
B. Dynamic resistance
C. Forward biased resistance
D. Reverse based DC resistance

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B. Dynamic resistance

3. A diodes' PIV in a half wave rectifier employing capacity filter is

A. V_m
B. 2V_m
C. Any ratio of V_m can be used
D. 0.5V_m

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B. 2V_m

4. The motion of hole is referred as

A. Bipolar
B. Electron motion
C. Conduction current
D. The vacancy being filled by a valance electron from a neighbouring atom

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D. The vacancy being filled by a valance electron from a neighbouring atom

5. Diffusion process is restricted in P-N junction diode formation by

A. Dopping level
B. Depletion region
C. Reverse based DC resistance
D. Dynamic resistance

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B. Depletion region

6. P-type extrinsic semiconductor producer by

A. Donor dopping
B. Highly donor dopping
C. Acceptor dopping
D. Either dopping

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C. Acceptor dopping

7. Temperature dependent factors in P-N junction diode are

A. V_T and Percentage efficiency
B. V_F and I_D
C. I_F and Percentage efficiency
D. V_T and I_F

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D. V_T and I_F

8. Electrically the charge of atom is

A. Positive
B. Negative
C. Neutral
D. Can't be determined

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C. Neutral

9. A power supply has a full load voltage of 24 V.Its no-load voltage for 0% regulation is

A. 24 V
B. 48 V
C. 12 V
D. 0 V

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A. 24 V

10. Majority carriers in 'N' type semiconductor is

A. Electrons
B. Neutrons
C. Holes
D. Ions

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A. Electrons

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