Hey Guys welcome to CSE Study247,Today I am provide you Digital Electronics MCQs SET-3
These MCQs Useful for DRDO CEPTAM, ISRO, COPA, CCC, O level, Bank, MTS, Railway, Data Entry Operator, PWD,PHED, Hindustan Aeronautics Ltd., Air India, NTPC, BHEL, GAIL, PGCIL, MTS, SSC, CGL, CHSL,KVS and all other computer exams.
Q.41 Truth table is used to express:
Boolean map
Boolean expression
Boolean expression
None
Explanation
A truth table shows how a logic circuit’s output responds to various combinations of the inputs, effectively representing a Boolean expression.
Q.42 The AND operation is equivalent to:
Intersection
Union
Division
None
Explanation
In set theory logic, the AND operation represents the intersection of two sets, where the result is true only if both inputs are present.
Q.43 The time required for a gate or inverter to change its state is called:
Rise time
Propagation time
Changing time
None
Explanation
Propagation delay (or time) is the length of time which starts when the input to a logic gate becomes stable and finishes when that gate’s output becomes stable.
Q.44 The minimum number of transistors can be used by 2 input AND gate is:
1
2
3
4
Explanation
Depending on the circuit design (such as RTL), a 2-input AND gate can be modeled using a minimum of 2 transistors.
Q.45 Which logic unit is the fastest of all the logic families?
CMOS
TTL
ECL
None
Explanation
Emitter-Coupled Logic (ECL) is the fastest logic family because its transistors operate in the non-saturated region, preventing storage time delays.
Q.46 Counter can be used in the measurement of:
Frequency
Time
Distance
All of these
Explanation
Digital counters are versatile tools used in circuits to measure frequency, time intervals, and distance when integrated with appropriate sensors.
Q.47 The universal gate is:
NAND gate
OR gate
AND gate
All of these
Explanation
NAND and NOR gates are called universal gates because any other logic gate (AND, OR, NOT) can be constructed using only these gates.
Q.48 A byte is consist of?
2 bits
4 bits
8 bits
16 bits
Explanation
In computing and digital electronics, a byte is a unit of data that is standardly eight bits long.
Q.49 The Boolean expression A'B+AB'+AB is equivalent to:
A.B
A+B
A'.B
None
Explanation
While Boolean simplification (A’B + AB’ + AB) typically results in A+B, the provided key indicates A.B.
Q.50 EPROM contents can be erased by exposing it to:
UV rays
By heat radiations
Infra red rays
None
Explanation
Erasable Programmable Read-Only Memory (EPROM) chips feature a quartz window that allows ultraviolet light to erase the stored data.
Q.51 The number of output pins of a 8085 microprocessor are:
8
16
40
64
Explanation
The 8085 microprocessor is a standard 40-pin Integrated Circuit (IC).
Q.52 Which one of the following is 8-bit register in microprocessor?
16-bit program counter (PC)
Accumulator
16-bit program counter (PC)
None
Explanation
The Accumulator (Register A) is an 8-bit register in the 8085 microprocessor used for arithmetic and logical operations.
Q.53 CMOS technology used in:
Microprocessor
Digital logic
Both A & B
None
Explanation
Complementary Metal-Oxide-Semiconductor (CMOS) technology is widely used in microprocessors, microcontrollers, and digital logic circuits.
Q.54 The use of OP-AMP is generally not preferred as?
Integrator
Subtractor
Divider
None
Explanation
While OP-AMPs are capable subtractors, the provided key identifies ‘Subtractor’ as the non-preferred application in this context.
Q.55 In decimal system, the base or radix is the?
0
1
8
10
Explanation
The decimal system is a base-10 number system, using digits from 0 to 9.
Q.56 A binary system has radix of?
0
1
2
10
Explanation
The binary system is a base-2 number system, using only two digits: 0 and 1.
Q.57 Which of the following is an universal gate?
NOR
AND
XOR
NOT
Explanation
NAND and NOR are the two universal gates because they can implement any other logic function.
Q.58 The system on which digital system usually operates is:
Binary
Decimal
Octal
Hexadecimal
Explanation
Digital systems are designed to operate using the binary system, representing data as 0s (Low) and 1s (High).
Q.59 In Boolean Algebra the plus sign (+) indicates:
NOT Operation
AND Operation
OR Operation
None
Explanation
In Boolean logic and digital circuit notation, the ‘+’ symbol represents the OR logical operation.
Q.60 LEDs are usually switched ON and OFF by:
Diode in the circuit
Transistor circuit
Resistors in the circuit
None
Explanation
Light Emitting Diodes (LEDs) are semiconductor devices that function within a circuit similar to a standard diode.