Electronic Circuits I Set 1 MCQs

Q1 | Which of the following condition is true for cut-off mode?

the collector current is zero

the collector current is proportional to the base current

the base current is non zero

all of the mentioned

Q2 | Which of the following is true for the cut- off region in an npn transistor?

potential difference between the emitter and the base is smaller than 0.5v

potential difference between the emitter and the base is smaller than 0.4v

the collector current increases with the increase in the base current

the collector current is always zero and the base current is always non zero

Q3 | Which of the following is true for a typical active region of an npn transistor?

the potential difference between the emitter and the collector is less than 0.5 v

the potential difference between the emitter and the collector is less than 0.4 v

the potential difference between the emitter and the collector is less than 0.3 v

the potential difference between the emitter and the collector is less than 0.2 v

Q4 | Which of the following is true for the active region of an npn transistor?

the collector current is directly proportional to the base current

the potential difference between the emitter and the collector is less than 0.4 v

all of the mentioned

none of the mentioned

Q5 | Which of the following is true for a npn transistor in the saturation region?

the potential difference between the collector and the base is approximately 0.2v

the potential difference between the collector and the base is approximately 0.3v

the potential difference between the collector and the base is approximately 0.4v

the potential difference between the collector and the base is approximately 0.5v

Q6 | The potential difference between the base and the collector Vcb in a pnp transistor in saturation region is

-0.2 v

-0.5v

0.2 v

0.5 v

Q7 | For a pnp transistor in the active region the value of Vce (potential difference between the collector and the base) is

less than 0.3v

less than 3v

greater than 0.3v

greater than 3v

Q8 | Which of the following is true for a pnp transistor in active region?

cb junction is reversed bias and the eb junction is forward bias

cb junction is forward bias and the eb junction is forward bias

cb junction is forward bias and the eb junction is reverse bias

cb junction is reversed bias and the eb junction is reverse bias

Q9 | Which of the following is true for a pnp transistor in saturation region?

cb junction is reversed bias and the eb junction is forward bias

cb junction is forward bias and the eb junction is forward bias

cb junction is forward bias and the eb junction is reverse bias

cb junction is reversed bias and the eb junction is reverse bias

Q10 | For the circuit shown, find the quiescent point.

none of the below

(4v, 10ma)

(10v, 3ma)

(3ma, 10v)

Q11 | What is the DC characteristic used to prove that the transistor is indeed biased in saturation mode?

ic = βib

ic > βib

ic >> βib

ic < βib

Q12 | For the circuit shown, find the quiescent point.

none of the below

(4v, 10ma)

(10v, 3ma)

(3ma, 10v)

Q13 | The feature of an approximate model of a transistor is

it helps in quicker analysis

it provides individual analysis for different configurations

it helps in dc analysis

ac analysis is not possible

Q14 | 005mmhos, hre=0. Find the output impedance if the lad resistance is 5kΩ.

5kΩ

4kΩ

20kΩ

15kΩ

Q15 | A transistor has hie =2kΩ, hoe=25µmhos and hfe=60 with an unbypassed emitter resistor Re=1kΩ. What will be the input resistance and output resistance?

90kΩ and 50kΩ respectively

33kΩ and 45kΩ respectively

6kΩ and 40kΩ respectively

63kΩ and 40kΩ respectively

Q16 | A transistor has hie =1KΩ and hfe=60 with an bypassed emitter resistor Re=1kΩ. What will be the input resistance and output resistance?

90kΩ and 50kΩ respectively

33kΩ and 45kΩ respectively

6kΩ and 40kΩ respectively

63kΩ and 40kΩ respectively

Q17 | In the given circuit, find the equivalent resistance between A and B nodes.

100kΩ

50kΩ

40kΩ

60kΩ

Q18 | Which of the following acts as a buffer?

cc amplifier

ce amplifier

cb amplifier

cascaded amplifier

Q19 | Which of the following is true?

cc amplifier has a large current gain

ce amplifier has a large current gain

cb amplifier has low voltage gain

cc amplifier has low current gain

Q20 | In CB configuration, the value of α=0.98A. A voltage drop of 4.9V is obtained across the resistor of 5KΩ when connected in collector circuit. Find the base current.

0.01ma

0.07ma

0.02ma

0.05ma

Q21 | Which of the following is the correct relationship between base and emitter current of a BJT?

ib = β ie

ib = ie

ib = (β + 1) ie

ie = (β + 1) ib

Q22 | For best operation of a BJT, which region must the operating point be set at?

active region

cutoff region

saturation region

reverse active region

Q23 | From the given circuit, using a silicon transistor, what is the value of IBQ?

47.08 ma

47.08 ua

50 ua

0 ma

Q24 | From the given circuit, using a silicon BJT, what is the value of VCEQ?

7 v

0.7 v

6.83 v

7.17 v

Q25 | From the given circuit, using a silicon BJT, what is the value of VBC?

6.13 v

-6.13 v

7 v

-7 v