250+ TOP MCQs on The Arithmetic & Logic Unit and Answers

Computer Fundamentals Multiple Choice Questions on “The Arithmetic & Logic Unit”.

1. The ‘heart’ of the processor which performs many different operations _____________
a) Arithmetic and logic unit
b) Motherboard
c) Control Unit
d) Memory

Answer: a
Clarification: The Arithmetic and logic unit performs all the basic operations of the computer system. It performs all the arithmetic(+,-,*,/,etc) as well as the logical operations( AND, OR, NOT, etc.).

2. ALU is the place where the actual executions of instructions take place during the processing operation.
a) True
b) False

Answer: a
Clarification: ALU is a combinational electronic circuit which basically performs all the logical or the bitwise operations and the arithmetic operations. Therefore, it is the place where the actual executions of instructions take place.

3. Which of the following is not a bitwise operator?
a) |
b) ^
c) .
d) <<

Answer: c
Clarification: All except the dot(.) operator are bitwise operators.
| : Bitwise OR
^ : Bitwise XOR
<< : Shift Left

4. The sign magnitude representation of -1 is __________
a) 0001
b) 1110
c) 1000
d) 1001

Answer: d
Clarification: The first leftmost bit i.e. the most significant bit in the sign magnitude represents if the number is positive or negative. If the MSB is 1, the number is negative else if it is 0, the number is positive. Here, +1=0001 and for -1=1001.

5. IEEE stands for ___________
a) Instantaneous Electrical Engineering
b) Institute of Emerging Electrical Engineers
c) Institute of Emerging Electronic Engineers
d) Institute of Electrical and electronics engineers

Answer: d
Clarification: The IEEE is an organization of professionals in the field of electronics and electrical engineering. IEEE has given certain standards of its own which are followed in the field of computer science and electrical engineering.

6. The ALU gives the output of the operations and the output is stored in the ________
a) Memory Devices
b) Registers
c) Flags
d) Output Unit

Answer: b
Clarification: Any output generated by the ALU gets stored in the registers. The registers are the temporary memory locations within the processor that are connected by signal paths to the CPU.

7. The process of division on memory spaces is called ______________
a) Paging
b) Segmentation
c) Bifurcation
d) Dynamic Division

Answer: b
Clarification: The memory space is divided into segments of dynamic size. The programmer is aware of the segmentation and can reallocate the segments accordingly.

8. Number of bits in ALU is _________
a) 4
b) 8
c) 16
d) 2

Answer: c
Clarification: Arithmetic and Logic Unit consists of 16bits. They perform certain Arithmetic and bitwise operations (add, subtract, AND, OR, XOR, Increment, decrement, shift).

9. Which flag indicates the number of 1 bit that results from an operation?
a) Zero
b) Parity
c) Auxiliary
d) Carry

Answer: b
Clarification: The parity flag indicates the number of 1 bit in any operation. The resultant bit is called the parity bit. The main aim of the parity bit is to check for errors.

10. The bitwise complement of 0 is ___________
a) 00000001
b) 10000000
c) 11111111
d) 11111110

Answer: c
Clarification: Bitwise complement is basically used to convert all the 0 digits to 1 and the 1s to 0s.
So, for 0 = 00000000(in 8-bits) ::: 11111111(1s complement). The bitwise complement is often referred to as the 1s complement.