Explore topic-wise MCQs in ENGINEERING SERVICES EXAMINATION (ESE).

This section includes 2171 Mcqs, each offering curated multiple-choice questions to sharpen your ENGINEERING SERVICES EXAMINATION (ESE) knowledge and support exam preparation. Choose a topic below to get started.

201.

In the 8421 BCD code, the decimal number 125, is written as

A. 1111101
B. 0001 0010 0101
C. 7 D
D. none of these
Answer» B. 0001 0010 0101
202.

For the given truth table, the correct Boolean expression is

A. A
B. B
C. C
D. D
Answer» C. C
203.

Which of the following logic no resistors are used?

A. CMOS
B. TTL
C. 4 n sec ECL
D. 8 sec ECL
Answer» B. TTL
204.

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
205.

Which binary subtraction is incorrect?

A. 100101 - 100011 = 000000
B. 10000000 - 01000000 = 1000000
C. 10111110.1 - 101011.11 = 110010.11
D. 11111111 - 1111111 = 10000000
Answer» B. 10000000 - 01000000 = 1000000
206.

A (A + B) =

A. A
B. B
C.
D.
Answer» B. B
207.

Find the FSV (full scale voltage) in a 6 bit R-2R ladder D/A converter has a reference voltage of 6.5 V.

A. 6.4 V
B. 0.1 V
C. 7 V
D. 8 V
Answer» B. 0.1 V
208.

BCD numbers are useful whenever

A. binary to hexadecimal conversion is desired
B. binary to BCD conversion is desired
C. decimal information is transferred into or out of a digital system
D. none of the above
Answer» D. none of the above
209.

The high voltage level of a digital signal in positive logic is

A. 1
B. 0
C. either 1 or 0
D. -1
Answer» B. 0
210.

AECF1₁₆ + 15ACD₁₆ = __________ .

A. C47BB₁₆
B. C47BE₁₆
C. A234F₁₆
D. A1111₁₆
Answer» C. A234F₁₆
211.

A twisted ring counter consisting of 4 FF will have

A. 4 states
B. 8 states
C. 2⁴ states
D. None of the above
Answer» C. 2⁴ states
212.

In a shift left register, shifting a bit by one bit means

A. division by 2
B. multiplication by 2
C. subtraction of 2
D. None of the above
Answer» C. subtraction of 2
213.

The given figure shows a K-map for a Boolean function. The number of essential prime implicants is

A. 4
B. 5
C. 6
D. 8
Answer» B. 5
214.

Assertion (A): Gate triggering is the most commonly used method for triggering of an SCR.Reason (R): Even a small gate current is sufficient to turn on an 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» B. Both A and R correct but R is not correct explanation of A
215.

The sum S of A and B in a Half Adder can be implemented by using K NAND gates. The value of K is

A. 3
B. 4
C. 5
D. none of these
Answer» C. 5
216.

In 2's complement addition, the carry generated in the last stage is

A. added to LSB
B. neglected
C. added to bit next to MSB
D. added to the bit next to LSB
Answer» C. added to bit next to MSB
217.

If an inverter is placed at the input to an SR flip-flop, the result is

A. T flip-flop
B. D flip-flop
C. JK flip-flop
D. BCD decade counter
Answer» C. JK flip-flop
218.

The open wired circuit in the given figure works as a

A. EX - NOR gate
B. AND gate
C. XOR gate
D. NOR gate
Answer» D. NOR gate
219.

Assertion (A): Demorgan's first theorem replaces a NOR gate by bubbled AND gate.Reason (R): Double complement of a variable equals the variable.

A. Both A and R are correct and R is correct explanation of A
B. Both A and R are correct but R is not correct explanation of A
C. A is true, R is false
D. A is false, R is true
Answer» C. A is true, R is false
220.

Each cell of a static RAM has

A. 4 MOS transistors
B. 4 MOS transistors and 2 capacitors
C. 2 MOS transistors and two capacitors
D. 1 MOS transistor and 1 capacitor
Answer» B. 4 MOS transistors and 2 capacitors
221.

In an 8085 microprocessor, the instruction CMP B has been executed while the content of the accumulator is less than that of register B, As a result.

A. carry flag will be set but zero flag will be reset
B. carry flag will be reset but zero flag will be set
C. both carry flag and zero flag will be reset
D. both carry flag and zero flag will be set
Answer» B. carry flag will be reset but zero flag will be set
222.

In 8085 microprocessor, an interrupt service request is serviced

A. immediately on receipt of request
B. after the execution of the current instruction is completed
C. at the end of the current machine cycle
D. none
Answer» C. at the end of the current machine cycle
223.

A 12 bit ADC is operating with 1 μs clock period. Total conversion time is 14 μs. ADC is

A. flash type
B. counting type
C. integrating type
D. successive approximation type
Answer» D. successive approximation type
224.

When a binary adder is used as BCD adder, the sum is

A. correct when it is < 9
B. correct when it is > 9
C. correct when it is < 16
D. none of these
Answer» B. correct when it is > 9
225.

A 4 bit DAC gives an output of 4.5 V for input of 1001. If input is 0110, the output is

A. 1.5 V
B. 2.0 V
C. 3.0 V
D. 4.5 V
Answer» D. 4.5 V
226.

In INHIBIT operation

A. output is 1 when both inputs are 0
B. output is 0 when blocking input is 1
C. output is 0 when blocking input is 0
D. output is 1 when blocking input is either 0 or 1
Answer» C. output is 0 when blocking input is 0
227.

The process of entering data into ROM is called

A. writing
B. burning
C. decoding
D. registering
Answer» C. decoding
228.

The PC contains 0450 H and SP contains 08D 6 H. What will be content of P and SP following a CALL to subroutine at location 02 AFH?

A. 0453 H, 08 D 8 H
B. 0453 H, 08 D 4 H
C. 02 AFH, 08 D 8 H
D. 02 AFH, 08 D 4 H
Answer» E.
229.

The Boolean expression Y = (A + B̅ + A̅B) C̅ then Y will be equal to

A. AC̅
B. BC̅
C.
D. none
Answer» D. none
230.

The Boolean function A + BC is reduced form of

A. AB + BC
B. A̅B + A̅BC
C. (A + B) (A + C)
D. (A + C)B
Answer» D. (A + C)B
231.

A clock signal coordinates the working of different flip flops.

A. True
B. False
C. May be True or False
D. Can't say
Answer» B. False
232.

In LIFO

A. only the top of the stack is immediately accessible
B. only the top of the stack is never accessible
C. only the first-in is accessible
D. only the first-in is not accessible
Answer» B. only the top of the stack is never accessible
233.

Consider the following digital circuits: 1. Multipliers2. Read only memories3. D-latch4. Circuits as shown in figureWhich of these come under the class of combinational circuit?

A. 1 and 2
B. 3 and 4
C. 1, 2 and 3
D. 1, 2, 3 and 4
Answer» B. 3 and 4
234.

Decimal number 9 in gray code =

A. 1100
B. 1101
C. 110
D. 1111
Answer» C. 110
235.

A 6 MHz channel is used by a digital signalling system initializing four-level signals. The maximum possible transmission rate is

A. 6M bands/s
B. 12M bands/s
C. 6 M bits/s
D. 12M bits/s
Answer» B. 12M bands/s
236.

The product of which of the following gives the figure of merit of a logic family?

A. Gain and bandwidth
B. Propagation delay time and power dissipation
C. Fan-out and propagation delay time
D. Noise margin and power dissipation
Answer» C. Fan-out and propagation delay time
237.

A presettable counter with 4 flip flops can start counting from

A. 0000
B. 1000
C. any number from 0000 to 1000
D. any number from 0000 to 1111
Answer» E.
238.

The decimal equivalent of the hexadecimal number (3 E 8)₁₆ is

A. 1000
B. 982
C. 768
D. 323
Answer» B. 982
239.

Which multivibrator can be used as a clock timer?

A. Astable multivibrator
B. Bistable multivibrator
C. Any of the above
D. None of the above
Answer» B. Bistable multivibrator
240.

Two 16 : 1 and one 2 : 1 multiplexers can be connected to form a

A. 16 : 1 multiplexer
B. 32 : 1 multiplexer
C. 64 : 1 multiplexer
D. 8 : 1 multiplexer
Answer» C. 64 : 1 multiplexer
241.

Which of the following logic family is fastest of all?

A. TTL
B. RTL
C. DCTL
D. ECL
Answer» E.
242.

Programmable logic array uses

A. RAM matrices
B. ROMs matrices
C. PROM matrices
D. Silo memory
Answer» C. PROM matrices
243.

Out of multiplexer and demultiplexer, which can be used as a logic function generator?

A. Multiplexer only
B. Demultiplexer only
C. Both
D. None
Answer» B. Demultiplexer only
244.

State transition table and state transition diagram form part of design steps for

A. combinational circuits
B. sequential circuits
C. delay circuits
D. all of the above
Answer» C. delay circuits
245.

For the K map in the given figure, the simplified expression is

A. A
B. B
C. C
D. D
Answer» C. C
246.

The most commonly used logic family is

A. ECL
B. TTL
C. CMOS
D. PMOS
Answer» C. CMOS
247.

Assuming accumulator contain A 64 and the carry is set (1). What will register A and (CY) contain after ADI A4H?

A. 4 AH, 0
B. 4 AH, 1
C. 4 BH, 0
D. 4 BH, 1
Answer» C. 4 BH, 0
248.

Logic hardware is available only in NAND and NOR.

A. True
B. False
C. May be True or False
D. Can't say
Answer» C. May be True or False
249.

Flow charts that contain decision symbol

A. represent straight line programs
B. do not represent straight line programs
C. all of the above
D. none of the above
Answer» C. all of the above
250.

The output of the circuit shown below will be of the frequency

A. 125 Hz
B. 250 Hz
C. 500 Hz
D. 750 Hz
Answer» C. 500 Hz