Explore topic-wise MCQs in Engineering.

This section includes 9294 Mcqs, each offering curated multiple-choice questions to sharpen your Engineering knowledge and support exam preparation. Choose a topic below to get started.

1.

What about the stability of system in

A. system is stable
B. unstable
C. stable at 0.4
D. cant say
Answer» B. unstable
Discussion
2.

An energy signal has G(f) = 10. Its energy density spectrum is

A. 10
B. 100
C. 50
D. 20
Answer» C. 50
Discussion
3.

The first geostationary satellite launched in 1965 was called

A. ANIK
B. EARLY BIRD (Intelsat-I)
C. WESTAR
D. MOLNIYA
Answer» C. WESTAR
Discussion
4.

Rotation of a geosynchronous satellite means its

A. drift from stationary position
B. wobbling
C. three-axis stabilization
D. three-dimensional stabilization
Answer» C. three-axis stabilization
Discussion
5.

The present total cost per watt of power generation in geosynchronous orbit is nearly Rs.

A. 20
B. 50
C. 100
D. 5
Answer» B. 50
Discussion
6.

For F1 layer the maximum ionic density is 2.3 x 104 electrons per cc. The critical frequency for this layer will be

A. 1.36 MHz
B. 13.6 MHz
C. 136 MHz
D. 1360 MHz
Answer» C. 136 MHz
Discussion
7.

Which one of the following does represents the electric field lines for the TE02 mode in the cross section of a hollow rectangular metallic waveguide?

A. <img src="/_files/images/electronics-and-communication-engineering/electromagnetic-field-theory/195-228-1.png">
B. <img src="/_files/images/electronics-and-communication-engineering/electromagnetic-field-theory/195-228-2.png">
C. <img src="/_files/images/electronics-and-communication-engineering/electromagnetic-field-theory/195-228-3.png">
D. <img src="/_files/images/electronics-and-communication-engineering/electromagnetic-field-theory/195-228-4.png">
Answer» D. <img src="/_files/images/electronics-and-communication-engineering/electromagnetic-field-theory/195-228-4.png">
Discussion
8.

Radiation intensity of a dipole depends strongly on frequency. If at a frequency f, the intensity of radiation is 'I'. Then at a frequency of f/2, the intensity will be

A. <img src="/_files/images/electronics-and-communication-engineering/electromagnetic-field-theory/203-419-1.png">
B. <img src="/_files/images/electronics-and-communication-engineering/electromagnetic-field-theory/203-419-2.png">
C. <img src="/_files/images/electronics-and-communication-engineering/electromagnetic-field-theory/203-419-3.png">
D. <img src="/_files/images/electronics-and-communication-engineering/electromagnetic-field-theory/203-419-4.png">
Answer» B. <img src="/_files/images/electronics-and-communication-engineering/electromagnetic-field-theory/203-419-2.png">
Discussion
9.

The input impedance of short-circuited line of length l where /4 &lt; l &lt; /2, is

A. resistive
B. inductive
C. capacitive
D. none of the above
Answer» D. none of the above
Discussion
10.

A wave is propagated in a waveguide at frequency of 9 GHz and separation is 2 cm between walls find cut off wavelength for dominant mode.

A. 4 cm
B. 1 cm
C. 2 cm
D. 8 cm
Answer» B. 1 cm
Discussion
11.

Find the radiation resistance of an antenna of length /10 meter?

A. 8 &ohm;
B. 780 &ohm;
C. 7.8 &ohm;
D. 78 &ohm;
Answer» D. 78 &ohm;
Discussion
12.

Current derating may be necessary when thyristors are operating in

A. series
B. parallel
C. series or parallel
D. none of the above
Answer» C. series or parallel
Discussion
13.

Assertion (A): Power transistor has lower switching time than SCR Reason (R): Power transistor has greater switching time than SCR

A. Both A and R are correct and R is correct explanation of A
B. Both A and R correct but R is not correct explanation of A
C. A is correct but R is wrong
D. A is wrong but R is correct
Answer» E.
Discussion
14.

A 3 kV circuit uses SCR of 800 V rating. If derating is 25%, the number of SCRs in series is

A. 4
B. 5
C. 6
D. 8
Answer» C. 6
Discussion
15.

For a 12 pulse operation, the two 6 pulse units are fed by

A. Y - Y and Y - Y transformers
B. - and - transformers
C. Y - Y and Y - transformers
D. Y - and Y - transformers
Answer» D. Y - and Y - transformers
Discussion
16.

A single phase semiconverter is feeding a highly inductive load and has freewheeling diode across the load. The waveshapes of output voltage and output current

A. are similar
B. are not similar
C. may be similar or dissimilar
D. are similar only if firing angle is zero
Answer» C. may be similar or dissimilar
Discussion
17.

The number of distinct Boolean expression of 4 variables is

A. 16
B. 256
C. 1024
D. 65536
Answer» E.
Discussion
18.

The fixed count that should be used so that the output register will represent the input for a 6 bit dual slope A/D converter uses a reference of -6v and a 1 MHz clock. It uses a fixed count of 40 (101000).

A. 000110
B. 0010
C. 1111
D. 011101
Answer» B. 0010
Discussion
19.

A memory system of size 16 k bytes is to be designed using memory chips which have 12 address lines and 4 data lines each. The number of such chips required to design the memory system is

A. 2
B. 4
C. 8
D. 18
Answer» D. 18
Discussion
20.

In a 7 segment display, LEDs b and c lit up. The decimal number displayed is

A. 9
B. 7
C. 3
D. 1
Answer» E.
Discussion
21.

7BF16 = __________ 2

A. 0111 1011 1110
B. 0111 1011 1111
C. 0111 1011 0111
D. 0111 1011 0011
Answer» C. 0111 1011 0111
Discussion
22.

A counter type A/D converter contains a 4 bit binary ladder and a counter driven by a 2 MHz clock. Then conversion time

A. 8 sec
B. 10 sec
C. 2 sec
D. 5 sec
Answer» B. 10 sec
Discussion
23.

Zero suppression is not used in actual practice.

A. True
B. False
Answer» C.
Discussion
24.

The hexadecimal number (3E8)16 is equal to decimal number

A. 1000
B. 982
C. 768
D. 323
Answer» B. 982
Discussion
25.

AB + AB =

A. B
B. A
C. 1
D. 0
Answer» C. 1
Discussion
26.

In a BCD to 7 segment decoder the minimum and maximum number of outputs active at any time is

A. 2 and 7
B. 3 and 7
C. 1 and 6
D. 3 and 6
Answer» B. 3 and 7
Discussion
27.

A three state switch has three outputs. These are

A. low, low and high
B. low, high, high
C. low. floating, low
D. low, high, floating
Answer» E.
Discussion
28.

1's complement of 11100110 is

A. 00011001
B. 10000001
C. 00011010
D. 00000000
Answer» B. 10000001
Discussion
29.

Which device has one input and many outputs?

A. Multiplexer
B. Demultiplexer
C. Counter
D. Flip flop
Answer» C. Counter
Discussion
30.

Minimum number of 2-input NAND gates required to implement the function F = (x + y) (Z + W) is

A. 3
B. 4
C. 5
D. 6
Answer» C. 5
Discussion
31.

A carry look ahead adder is frequently used for addition because

A. it costs less
B. it is faster
C. it is more accurate
D. is uses fewer gates
Answer» C. it is more accurate
Discussion
32.

The counter in the given figure is

A. Mod 3
B. Mod 6
C. Mod 8
D. Mod 7
Answer» C. Mod 8
Discussion
33.

For the truth table of the given figure Y =

A. A + B + C
B. <span style="text-decoration:overline;">A</span>
C. + BC
D. <span style="text-decoration:overline;">A</span>
E. <span style="text-decoration:overline;">B</span>
Answer» E. <span style="text-decoration:overline;">B</span>
Discussion
34.

A 12 bit ADC is used to convert analog voltage of 0 to 10 V into digital. The resolution is

A. 2.44 mV
B. 24.4 mV
C. 1.2 V
D. none of the above
Answer» B. 24.4 mV
Discussion
35.

In register index addressing mode the effective address is given by

A. index register value
B. sum of the index register value and the operand
C. operand
D. difference of the index register value and the operand
Answer» C. operand
Discussion
36.

A full adder can be made out of

A. two half adders
B. two half adders and a OR gate
C. two half adders and a NOT gate
D. three half adders
Answer» C. two half adders and a NOT gate
Discussion
37.

If the functions w, x, y, z are as follows.w = R + PQ + RS , x = PQR S + PQR S + PQ R SThen

A. <i>w = z x = z</i>
B. <i>w = z, x = y</i>
C. <i>w = y</i>
D. <i>w = y = z</i>
Answer» B. <i>w = z, x = y</i>
Discussion
38.

The output of a half adder is

A. SUM
B. CARRY
C. SUM and CARRY
D. none of the above
Answer» D. none of the above
Discussion
39.

An AND gate has two inputs A and B and one inhibit input 3, Output is 1 if

A. A = 1, B = 1, S = 1
B. A = 1, B = 1, S = 0
C. A = 1, B = 0, S = 1
D. A = 1, B = 0, S = 0
Answer» C. A = 1, B = 0, S = 1
Discussion
40.

The greatest negative number which can be stored is 8 bit computer using 2's complement arithmetic is

A. - 256
B. - 128
C. - 255
D. - 127
Answer» C. - 255
Discussion
41.

For the gate in the given figure the output will be

A. 0
B. 1
C. A
D. <span style="text-decoration:overline;">A</span>
Answer» E.
Discussion
42.

In the expression A + BC, the total number of minterms will be

A. 2
B. 3
C. 4
D. 5
Answer» E.
Discussion
43.

The circuit in the given figure is

A. positive logic XOR gate
B. negative logic OR gate
C. negative logic AND gate
D. positive logic AND gate
Answer» D. positive logic AND gate
Discussion
44.

Which of the following is non-saturating?

A. TTL
B. CMOS
C. ECL
D. Both (a) and (b)
Answer» D. Both (a) and (b)
Discussion
45.

A device which converts BCD to seven segment is called

A. encoder
B. decoder
C. multiplexer
D. none of these
Answer» C. multiplexer
Discussion
46.

The number of digits in octal system is

A. 8
B. 7
C. 9
D. 10
Answer» B. 7
Discussion
47.

In 2's complement representation the number 11100101 represents the decimal number

A. +37
B. -31
C. +27
D. -27
Answer» E.
Discussion
48.

BCD input 1000 is fed to a 7 segment display through a BCD to 7 segment decoder/driver. The segments which will lit up are

A. <i>a, b, d</i>
B. <i>a, b, c</i>
C. all
D. <i>a, b, g, c, d</i>
Answer» D. <i>a, b, g, c, d</i>
Discussion
49.

The sensitivity curve of a standard receiver is represented by

A. curve A
B. curve B
C. curve C
D. curve D
Answer» D. curve D
Discussion
50.

A transponder is a satellite equipment which

A. receives a signal from Earth station and amplifies
B. changes the frequency of the received signal
C. retransmits the received signal
D. does all of the above-mentioned functions
Answer» E.
Discussion