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UGC-NET Electronic Science Question Paper With Answer Key and Full Explanation [2024]

 

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UGC-NET Electronic Science 2024 Answers with Explanations

1.

The peak concentration in the lateral autodoping profile is a function of the following parameters:

(a) Temperature
(b) Surface concentration in the buried layer
(c) Applied voltage
(d) Growth time

Options:

A. (a) and (b) only
B. (a) and (c) only
C. (a), (b) and (c) only
D. (a), (b) and (d) only

Answer: D

2.

A parallel plate capacitive transducer having air as dielectric between the plates, plate area is 50 mm × 50 mm and plate spacing is 0.5 mm. The displacement causes the capacitance to change by 10 pF. The sensitivity of the capacitive displacement transducer is:

A. 50.23 pF/mm
B. 66.67 pF/mm
C. 61.25 pF/mm
D. 59.12 pF/mm

Answer: B

3.

In a charge coupled device, the charge storage and transfer action is controlled by one of the following:

A. Drain Electrode
B. Gate Electrodes
C. Source Electrodes
D. Back of the Substrate

Answer: B

4.

Following set of instructions in 8086 searches a table of 100 bytes for 0AH. Select the correct option: 

MOV CX, 100
MOV AL, 0AH

(a) SCASB
(b) CLC
(c) CLD
(d) REPNE SCASB
(e) JCXZ NOT_FOUND

NOT FOUND : END
A. (a), (d), (b), (e), (c)
B. (b), (d), (a), (e), (c)
C. (c), (d), (a), (e), (b)
D. (b), (d), (c), (e), (a)

Answer: C

5.

The band gap of a semiconductor material that can be considered for making solar cell will be:

A. < 1 eV
B. Between 2 & 3 eV
C. Between 1 & 2 eV
D. > 3 eV

Answer: C

6.

Arrange the following in the decreasing order of their Bandgap (eV) at 300K.

(a) GaAs
(b) Si
(c) Ge
(d) ZnO
(e) InSb

Order: ZnO > GaAs > Si > Ge > InSb

Answer: D

7.

A thyristor having the equivalent capacitance of the depletion layer of reverse biased junction as 20 picofarad can be fired with a dv/dt of 120 V/ยตsec. The capacitive current flowing through the junction will be:

i = C (dv/dt)

A. 1.8 mA
B. 2.4 mA
C. 3.6 mA
D. 5.9 mA

Answer: B

8.

The circular loop of radius a carries current I. The magnetic field at an observation point in spherical coordinates is asked.



A. Hr = (I ฯ€a² cosฮธ) / (2ฯ€ r³)
B. Hr = (I ฯ€a² cosฮธ) / (2ฯ€ r²)
C. Hr = (I ฯ€a² sinฮธ) / (2ฯ€ r³)
D. Hr = (I ฯ€a² sinฮธ) / (4ฯ€ r³)

Answer: A

9.

A PMMC instrument has a three-resistor Ayrton shunt connected in parallel with it to make an ammeter. The current range when connected to terminal C is asked.



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

Answer: C

10.

Match the List-I with List-II (Input waveform with Output waveform).



Answer: A

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