Goa Board Class 12 Question Paper 2025 Industrial Electronics & Instrumentation

2025 II 24 0930 Seat No.

Time : 2 Hours INDUSTRIAL ELECTRONICS
AND INSTRUMENTATION
Subject Code

V 4 3 3 4

Total No. of Questions : 23 (Printed Pages : 4) Maximum Marks : 50

INSTRUCTIONS : (i) There are four sections in the question paper

(A, B, C and D) consisting of 23 questions.

(ii) In section A, there are eight questions of which

Q. Nos. 1 to 4 are multiple choice questions,

Q. Nos. 5 and 6 are to be answered in one/two words,

phrase or figure and Q. Nos. 7 and 8 are to be answered

in one sentence each.

(iii) All questions are compulsory, however there is internal

choice for Q. Nos. 20 and 23.

(iv) Figures to the right indicate marks allotted to each

question.

(v) Write the number of each question clearly on the answer-

book.

V-4334 1 P.T.O.

SECTION–‘A’
1. A photo diode is also known as ...................... . 1
• Photo detector

• Light dependent resistor

• Photo tube
• Photo relay

2. The maximum input voltage that can be connected to IC 7824 is ........ . 1
• +24 V

• + 35 V

• + 40 V

• + 50 V

3. The output waveform of an astable multivibrator using IC555 is ........ . 1

• square wave

• rectangular wave

• sine wave

• saw tooth wave

4. An electronic instrument used to detect metal in hidden places ............ . 1

• tong tester

• metal detector

• anemometer
• LVDT
5. Name the IC that can be used as an adjustable positive output voltage
regulator. 1

6. State one application of a radio frequency signal generator. 1
7. State any two applications of SCR. 1

8. Define instrumentation system. 1

V-4334 2

SECTION–‘B’

9. With the help of a labelled diagram explain how to convert D’ Arsonval meter
into an ammeter. 2

10. State any four features of IC555. 2

11. State two points of difference between SCR and TRIAC. 2

12. Draw a labelled diagram of a series dc motor and state any one application
of the same. 2

13. State the functions of cathode and heater in the electron gun assembly of
a cathode ray tube. 2

14. Explain the working principle of a permanent magnetic moving coil meter. 2

SECTION–‘C’

15. Briefly explain the working of a linear variable differential transducer
(LVDT). 3

16. Define photo resistive effect. Draw a labelled diagram of a LDR and also
state any one application of it. 3

17. The following is a block diagram of a CRO. Write down the names of the
missing blocks. 3

V-4334 3 P.T.O.

18. With the help of a block diagram explain the working of an AF signal
generator. 3

19. State any three differences between an online UPS and an offline UPS ? 3

20. With the help of a labelled diagram explain the working of a bonded strain
gauge. 3

Or

With the help of a labelled diagram explain the working of an unbonded
strain gauge. 3

SECTION–‘D’

21. With the help of a block diagram explain the working of an
electrocardiogram. 4

22. Explain the functions of the following parts of a DC motor : 4
(a) yoke
(b) armature winding
(c) carbon brushes
(d) bearings.

23. Draw the pin configuration diagram of IC555 and state the function of the
following pins : 4
(a) Pin 1
(b) Pin 3
(c) Pin 8.

Or

With the help of a neat circuit diagram explain the working of an astable
multivibrator using IC555 and also state the formula for time period. 4

V-4334 4