Objective question paper of fundamental of electronics Unit 01

1. The depletion layer of a Pn-junction is reduced when the junction is

(a) open circuit

(b) Forward Bias

(c) Reverse Bias

(d) All of the above

Ans :- (b)

(2) The knee voltage of an Si diode is

Ans:- 0.7 v

(3) The knee voltage of a Ge diode is

Ans:- 0.3v

(4) A silicon Pn-junction diode is forward biased and conducts. Then the voltage drop across the diode is about

Ans:- 0.7 v

(5) The reverse saturation current of a PN-JUNCTION diode is

Ans:- Increased with temperature

(6) The depletion layer of PN-JUNCTION diode is decreased when the junction is

Ans:-Forward bias

(7) The depletion layer of a Pn-junction diode is increased when the junction is

Ans:-Reverse Bias

(8) The width of depletion layer of a Pn-junction diode is

Ans:- increased with applied reverse-bias voltage

(9) When a diode is reversed biased,it is equivalent to

Ans:- Open-Switch

(10) The forward characteristics of a diode appear as 

Ans:- On- Switch

(11) The reverse saturation current is due to

Ans:- The minority charge

(12) A Pn-junction diode is used as

Ans:- A rectifier

(13) A ideal Pn-junction diode is one which behaves as a perfect -----  when forward biased.

Ans:- Conductor

(14) If the temperature of a Pn-junction diode increases, then leakage current -----.

Ans:- Increases

(15) A Pn-junction diode is a ----- device.

Ans:- Non-linear

(16) A zener diode has 

Ans:- One Pn-junction

(17) A zener diode is used as

Ans:- A voltage regulator

(18) A zener diode is always connected in

Ans:- Reverse

(19) A zener diode is utilses ------- characteristics for its operation.

Ans:- Reverse

(20) In the breakdown region,a zener diode behave like as

Ans:- Constant voltage source

(21) The doping level in a zener diode is---- that of a crystal diode.

Ans:- more than

(22) A zener diode is destroyed if it
Ans:- carries more than rated

(23) A zener diode is
Ans:- Non-linear device

(24) A power diode is a
Ans:- linear device

(25) The number of Pn-junction is a power diode
Ans:-. 1

(26). The number of semiconductor layer in a power diode is
Ans:- 3

(27). The varactor diode is usually
Ans:- Reversed biased

(28) A BJT is---- layer and-----terminal device
Ans:- Three, three

(29) A Bipolar junction transistor has
Ans:- Two Pn-junction

(30). How many depletion layer in a BJT.
Ans:- Two

(31) The heavily doped region of BJT is
Ans:- Emitter

(32) The base of transistor is ---- doped.
Ans:- Lightly

(33) The moderate size of region BJT is
Ans:- Emitter

(34) The element that has the biggest size in a transistor is
Ans:- Collector

(35) Types of BJT
(a) NPN BJT
(b) PNP BJT

(36) In a NPN BJT transistor, the current carrier are
Ans:- Electrons

(37)  In a NPN transistor, the minorities carriers are
Ans:- Holes

(38) In a PNP transistor, the current carrier are
Ans:- Holes

(39) In a PNP transistor, the minorities carriers are
Ans:- Free Electrons

(40) The diode which convert light signal into Electrical signal is called
Ans:- Photo diode

(41)  A photo diode always work in
Ans:- Reverse Biase

(43) LED always work in
Ans:-  Forward Biase

(44) when the light increases, the Reverse current in a photo-diode
Ans:- Increases

(45) A pn junction that radiates energy as light instead of as heat is called a
Ans:- LED

(46) LED full form
Ans:- Light Emitting Diode

(47) For a 7 - segment display how many LEDs are used
Ans:-  7

(48) The semiconductor material used in construction of LED to Emitting the infrared light is
Ans:- GaAs

(49) The LCD used to display ----- characters
Ans:- Both numeric and alphanumeric

(50) In a thermistor when the temperature is increases than resistance is ------
Ans:- Decreases

(51). The resistance of metal is  ----- with increased in temperature.
Ans:- Increased