Hey Guys welcome to CSE Study247 , Today I am provide you Digital Electronics MCQs SET-2.
Which is very 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
This page provide you Digital Electronics Multiple Choice Question Answer that is very useful for Semester , DRDO, ISRO ,Banking , Railway, Gate and another exam.
Q.21 Which of the following is minimum error code?
Octal code
Gray code
Binary code
Excess 3-code
Explanation
Gray code is known as a minimum error code (or cyclic code) because only one bit changes at a time between successive values, which minimizes errors during transitions.
Q.22 A NOT gate has-
Two input and one output
One input and one output
One input and two output
None of these
Explanation
A NOT gate, also known as an inverter, is a basic logic gate that has exactly one input and one output. It outputs the opposite logic level of its input.
Q.23 A set of instruction written in computer language is called the?
Software
Hardware
Program
None of these
Explanation
A computer program is a collection of instructions that can be executed by a computer to perform a specific task.
Q.24 1's complement of 10101 is given by?
01010
01011
10101
00100
Explanation
To find the 1’s complement of a binary number, you simply flip all bits: 1 becomes 0 and 0 becomes 1. Therefore, 10101 becomes 01010.
Q.25 The shift register is designed to shift data?
Only to left changing the order of the nits
Only to right changing the order of the bits
Either left or right changing the order of the bits
Either left or right without changing the order of the bits
Explanation
Shift registers are sequential logic circuits used for the storage or transfer of data. They can shift bits to the left or right, which changes the positional order of the bits.
Q.26 The 8085 instruction RAL performs the following operations?
Rotate the content of accumulator to the right
Rotate the content of accumulator to the left
Rotate the content of accumulator to the right through carry
Rotate the content of accumulator to the left through carry
Explanation
RAL stands for ‘Rotate Accumulator Left through Carry’. Each bit in the accumulator is shifted one position to the left, and the carry flag is moved into the least significant bit.
Q.27 Disc and Drum are the
Hardware part of the computer
Software part
Firmware
None of these
Explanation
Note: While technically hardware components used for storage, according to the provided key, these are categorized here as the software part context.
Q.28 Which of the following memories normally has highest storage capacity?
Magnetic disk
Magnetic tape
Semi conductor memory
Core memory
Explanation
Among the listed options, magnetic disks (like Hard Disk Drives) typically offer the highest non-volatile storage capacity for computer systems.
Q.29 OP-AMP's can be used to amplify:
D.C. input signal
A.C. input signal
D.C. as well as A.C. input signal
None of these
Explanation
Operational Amplifiers (Op-Amps) are versatile DC-coupled high-gain electronic voltage amplifiers that can amplify both Direct Current (DC) and Alternating Current (AC) signals.
Q.30 Number of interrupts of Intel 8085 are?
5
4
2
3
Explanation
The Intel 8085 microprocessor has 5 hardware interrupts: TRAP, RST 7.5, RST 6.5, RST 5.5, and INTR.
Q.31 A program written in mnemonics are called?
High level language program
Low level language program
Assembly level language program
None of these
Explanation
Assembly language uses mnemonics (like MOV, ADD, SUB) to represent machine-level instructions, making them easier for humans to write than pure binary code.
Q.32 One of the method is used for A/D conversion is:
R-2R ladder
Weighted binary resistors
Successive approximation
None of these
Explanation
Successive Approximation Register (SAR) is a common method for Analog-to-Digital (A/D) conversion. R-2R and Weighted binary methods are used for D/A (Digital-to-Analog) conversion.
Q.33 In a microcomputer——– is its heart?
Microprocessor
ALU
Control Unit
None of these
Explanation
The microprocessor is considered the heart/brain of a microcomputer because it performs all data processing and controls the other components.
Q.34 An R-S flip flop cannot be used to design T-type flip flop as?
R=0, S=1 is not permitted
R=0, S=0 is not permitted
R=1, S=0 is not permitted
R=1, S=1 is not permitted
Explanation
Based on the provided answer key, R=0, S=1 is cited, though in standard logic, R=1, S=1 is the ‘forbidden’ or ‘invalid’ state for an RS flip-flop.
Q.35 In Boolean Algebra the plus sign (+) indicates
AND Operation
OR Operation
NOT Operation
None
Explanation
In Boolean algebra, the plus sign (+) represents the logical OR operation, while the dot (.) represents the AND operation.
Q.36 Flip flop comes under the category of ?
2- bit storage device
1- bit storage device
Multi bit storage device
None of these
Explanation
A flip-flop is a fundamental bistable multivibrator used as a basic memory element to store exactly 1 bit of digital data.
Q.37 Extremely low power dissipation and low cost can be achieved in?
MOS ICs
CMOS ICs
TTL ICs
ECL ICs
Explanation
CMOS (Complementary Metal-Oxide-Semiconductor) technology is favored for its extremely low static power consumption and high noise immunity.
Q.38 The 8085 instruction INR r comes in the category ?
Machine control group
Branch group
Arithmetic group
Data transfer group
Explanation
The INR (Increment Register) instruction adds 1 to the contents of a specific register, placing it in the Arithmetic group of instructions.
Q.39 An ideal OP-AMP has?
Infinite Av
Infinite Ri
Zero
All of the above
Explanation
An ideal operational amplifier is characterized by infinite input impedance (Ri), which prevents it from drawing current from the input source.
Q.40 Which of the following Boolean rules is correct?
A + 0 = 0
A + 1 = 1
A + A compliment =A.A
A + AB = A compliment +B
Explanation
According to the laws of Boolean algebra, anything ORed with 1 results in 1 (A + 1 = 1).