MBOSE Class 12 Question Paper 2021 for Electronics and Hardware

Total No. of Printed Pages—4
HS/XII/V/EH/21

2021

ELECTRONICS AND HARDWARE
( Vocational Course )

( Installation Technician Computing Peripherals )

Full Marks : 30
Time : 1 hour

The figures in the margin indicate full marks for the questions

1. Choose the correct answer : 1×4=4
(a) Miniature circuit breaker is a small
(i) fuse

(ii) magnetic switch

(iii) electromagnetic switch

(iv) two-way switch

(b) A simple enclosed length of wire that has low
melting point is known as
(i) resistor

(ii) fuse

(iii) circuit breaker

(iv) thermistor

/140 [ P.T.O.

( 2 )

(c) SF6 gas is transported in

(i) air cylinder

(ii) gas cylinder

(iii) liquid form in cylinder

(iv) solid form

(d) The technology behind AC motor speed consists of

(i) rectifier unit

(ii) DC circuit

(iii) inverter unit

(iv) All of the above

2. Fill in the blanks : 1×4=4

(a) PLC stands for _____.

(b) The meter constant of single-phase energy meter is
expressed in terms of _____.

(c) The voltage of 3-phase system is _____.

(d) _____ is used to control the RPM of motor.

HS/XII/V/EH/21/140 [ Contd.

( 3 )

3. Answer the following in 1 word or 1 sentence each
(any four) : 1×4=4

(a) What is three-phase system?

(b) What is an alternator?

(c) What is relay?

(d) What is the function of PT?

(e) What is distribution transformer?

4. Answer the following in 3 or 4 sentences each
(any three) : 2×3=6

(a) What is a contactor? Draw the circuit connection of
motor using contactor.

(b) What is soft starter? Why is it needed?

(c) Explain with circuit diagram the two types of
connection in three-phase system.

(d) Differentiate between RCCB and ELCB.

(e) What is circuit breaker? Give its types.

HS/XII/V/EH/21/140 [ P.T.O.

( 4 )

5. Answer the following essay-type questions (any three) :
4×3=12
(a) Draw the block diagram of solar power energy and
explain the working principle and function of each
part.

(b) What is transformer? Differentiate between single-
phase and three-phase transformer.

(c) Explain with diagram the working and construction
of a current transformer.

(d) What is communication? Explain the method of
communication.

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HS/XII/V/EH/21/140 11-21—100