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Syllabus

NEC Computer · Practice

Chapters & sets

1. Basic Electrical and Electronics

Basic Electrical

Set 1106

Basic Electronics

Set 171 Set 233

2. Digital Logic and Microprocessor

Digital Logic

Set 150 Set 250 Set 350 Set 450 Set 550 Set 650 Set 749 Set 851 Set 950 Set 1050 Set 1150 Set 1232

Microprocessor

Set 150 Set 250 Set 350 Set 445 Set 550 Set 650 Set 720 Set 850 Set 969

3. Programming Language and Its Applications

Mixed chapter MCQs

Set 150 Set 249 Set 349 Set 451 Set 540

4. Computer Organization and Embedded System

Mixed chapter MCQs

Set 150 Set 249 Set 350 Set 450 Set 550 Set 650 Set 750 Set 849 Set 950 Set 1050 Set 1150

5. Concept of Computer Network and Network Security System

Basic Networking

Set 150 Set 253

Advanced Networking

Set 150 Set 250 Set 350 Set 450 Set 550 Set 655

6. Theory of Computation and Computer Graphics

Theory of Computation

Set 150 Set 250 Set 360

Computer Graphics

Set 150 Set 251 Set 350 Set 450 Set 550

7. Data Structures and Algorithm, Database System and Operating System

8. Software Engineering and Object-Oriented Analysis & Design

Mixed chapter MCQs

Set 150 Set 250 Set 350 Set 450 Set 550 Set 650 Set 750 Set 926

9. Artificial Intelligence and Neural Networks

Mixed chapter MCQs

Set 150 Set 317 Set 450 Set 550 Set 650 Set 750 Set 850 Set 932

10. Project Planning, Design and Implementation

Engineering Drawing

Set 150 Set 267

Engineering Economics

Set 168

Project Planning & Scheduling

Set 188

Project Mangement

Set 150

Engineering Professional Practice

Set 120

Engineering Regulatory Body

Set 130

Operating System Set 1

50 questions

Question 1

Virtual memory is:

A.
An extremely large main memory
B.
An extremely large secondary memory
C.
An illusion of an extremely large main memory
D.
A type of memory used in supercomputers

Question 2

50

Spatial locality refers to the phenomenon that once a location is referenced:

A.
It will not be referenced again
B.
It will be referenced again
C.
A nearby location will be referenced soon
D.
None of the above

Question 3

Which of the following is an example of a SPOOLED device?

A.
The terminal used to enter the input data for a program being executed
B.
The secondary memory device in a virtual memory system
C.
A line printer used to print the output of a number of jobs
D.
None of the above

Question 4

Page fault occurs when:

A.
The page is in main memory
B.
The page is not in main memory
C.
The page is corrupted by application software
D.
One tries to divide a number by 10

Question 5

Overlay is:

A.
A part of an operating system
B.
A specific memory location
C.
A single contiguous memory that was used in the olden days for running large programs by swapping
D.
Overloading the system with many user files

Question 6

Determine the number of page faults when reference to pages occurs in the order 1,2,3,4,5,2,1,2,4. Assume that the main memory can accommodate 3 pages and the main memory already has the pages 1 and 2, with page 1 having been brought earlier than page 2 (assume LRU algorithm is used).

A.
3
B.
4
C.
5
D.
None of the above

Question 7

Concurrent processes are processes that:

A.
Do not overlap in time
B.
Overlap in time
C.
Are executed by a processor at the same time
D.
None of the above

Question 8

The page replacement policy that sometimes leads to more page faults when the size of the memory is increased is:

A.
FIFO
B.
No such policy exists
C.
LRU
D.
None of the above

Question 9

The only state transition that is initiated by the user process itself is:

A.
Block
B.
Wake up
C.
Dispatch
D.
None of the above

Question 10

Working set (t, k) at an instant of time, t, is the set of:

A.
K future references that the operating system will make
B.
Future references that the operating system will make in the next ‘k’ time units
C.
K references with high frequency
D.
Pages that have been referenced in the last k time units

Question 11

Fragmentation is:

A.
Dividing the secondary memory into equal-sized fragments
B.
Dividing the main memory into equal-sized fragments
C.
Fragments of memory words used in a page
D.
Fragments of memory words unused in a page

Question 12

Which of the following are real-time systems?

A.
A process control system
B.
Aircraft control system
C.
An on-line railway reservation system
D.
Both (B) and (C)

Question 13

Dijkstra’s banking algorithm in an operating system solves the problem of:

A.
Deadlock avoidance
B.
Mutual exclusion
C.
Deadlock recovery
D.
Context switching

Question 14

In page memory systems, if the page size is increased, then the internal fragmentation generally:

A.
Becomes less
B.
Remains constant
C.
Becomes more
D.
None of the above

Question 15

An operating system contains 3 user processes each requiring 2 units of resource R. The minimum number of units of R such that no deadlock will ever occur is:

A.
3
B.
5
C.
4
D.
6

Question 16

Critical region is:

A.
A part of the operating system which is not allowed to be accessed by any process
B.
A set of instructions that access common shared resource which exclude one another in time
C.
The portion of the main memory which can be accessed only by one process at a time
D.
None of the above

Question 17

Kernel is:

A.
Considered as the critical part of the operating system
B.
The software which monitors the operating system
C.
The set of primitive functions upon which the rest of operating system functions are built up
D.
None of the above

Question 18

With a single resource, deadlock occurs:

A.
If there are more than two processes competing for that resource
B.
If there are only two processes competing for that resource
C.
If there is a single process competing for that resource
D.
None of the above

Question 19

Necessary conditions for deadlock are:

A.
Non-preemption and circular wait
B.
Both (A) and (B)
C.
Mutual exclusion and partial allocation
D.
None of the above

Question 20

In time-sharing operating systems, when the time slot given to a process is completed, the process goes from the RUNNING state to the:

A.
BLOCKED State
B.
SUSPENDED state
C.
READY state
D.
TERMINATED state

Question 21

At a particular time, the value of a counting semaphore is 10. It will become 7 after:

A.
3 V operations
B.
5 V operations and 2 P operations
C.
3 P operations
D.
13 P operations and 10 V operations

Question 22

Supervisor call:

A.
Is a call made by the supervisor of the system
B.
Is a call with control functions
C.
Are privileged calls that are used to perform resource management functions, which are controlled by the operating system
D.
Is a call made by someone working in the root directory

Question 23

Semaphores are used to solve the problem of:

A.
Race condition
B.
Mutual exclusion
C.
Process synchronization
D.
Both (B) and (C)

Question 24

If the property of locality of reference is well pronounced in a program:

A.
The number of page faults will be more
B.
The number of page faults will be less
C.
Execution will be faster
D.
Both (B) and (C)

Question 25

At a particular time of computation, the value of a counting semaphore is 7. Then 20 P operations and ‘x’ V operations were completed on this semaphore. If the final value of the semaphore is 5, x will be:

A.
15
B.
18
C.
22
D.
13

Question 26

Pre-emptive scheduling is the strategy of temporarily suspending a running process:

A.
Before the CPU time slice expires
B.
When it requests I/O
C.
To allow starving processes to run
D.
None of the above

Question 27

Mutual exclusion problem occurs:

A.
Between two disjoint processes that do not interact
B.
Among processes that share resources
C.
Among processes that do not use the same resource
D.
None of the above

Question 28

Sector interleaving in disks is done by:

A.
The disk manufacturer
B.
The operating system
C.
The disk controller cord
D.
None of the above

Question 29

Memory protection is of no use in a:

A.
Single-user system
B.
Non-multitasking system
C.
Non-multiprogramming system
D.
None of the above

Question 30

Some computer systems support dual-mode operation—the user mode and the supervisor or monitor mode. These refer to the modes:

A.
By which user programs handle their data
B.
By which the operating system executes user programs
C.
In which the processor and the associated hardware operate
D.
Of memory access

Question 31

Disk scheduling involves deciding:

A.
Which disk should be accessed next
B.
The order in which disk access requests must be serviced
C.
The physical location where files should be accessed in the disk
D.
None of the above

Question 32

A computer system has 6 tape drives, with ‘n’ processes competing for them. Each process may need 3 tape drives. The maximum value of ‘n’ for which the system is guaranteed to be deadlock-free is:

A.
2
B.
4
C.
3
D.
1

Question 33

Dirty bit is used to show the:

A.
Page with corrupted data
B.
Wrong page in the memory
C.
Page that is modified after being loaded into cache memory
D.
Page that is less frequently accessed

Question 34

Fence register is used for:

A.
CPU protection
B.
File protection
C.
Memory protection
D.
All of the above

Question 35

Which of the following is a service not supported by the operating system?

A.
Protection
B.
Compilation
C.
Accounting
D.
I/O operation

Question 36

The first-fit, best-fit, and worst-fit algorithms can be used for:

A.
Contiguous allocation of memory
B.
Indexed allocation of memory
C.
Linked allocation of memory
D.
All of the above

Question 37

Which of the following is a single-user operating system?

A.
MS-DOS
B.
XENIX
C.
UNIX
D.
Both (A) and (C)

Question 38

In Round Robin CPU scheduling, as the time quantum is increased, the average turnaround time:

A.
Increases
B.
Remains constant
C.
Decreases
D.
Varies irregularly

Question 39

In a multiprogramming environment:

A.
The processor executes more than one process at a time
B.
The programs are developed by more than one person
C.
More than one process resides in the memory
D.
A single user can execute many programs at the same time

Question 40

Which of the following are true?

A.
A re-entrant procedure can be called any number of times
B.
A re-entrant procedure can be called even before the procedure has not returned from its previous call
C.
Re-entrant procedures cannot be called recursively
D.
Re-entrant procedures can be called recursively

Question 41

In a paged memory, the page hit ratio is 0.35. The time required to access a page in secondary memory is equal to 100ns. The time required to access a page in primary memory is 10ns. The average time required to access a page is:

A.
3.0 ns
B.
68.0 ns
C.
68.5 ns
D.
78.5 ns

Question 42

A state is safe if the system can allocate resources to each process (up to its maximum) in some order and still avoid deadlock. Which of the following are true?

A.
Deadlock state is unsafe
B.
Unsafe state may lead to a deadlock situation
C.
Unsafe state must lead to a deadlock, deadlock state is a subset of unsafe state
D.
All of the above

Question 43

The size of the virtual memory depends on the size of the:

A.
Data bus
B.
Address bus
C.
Main memory
D.
None of the above

Question 44

In a multi-user operating system, 20 requests are made to use a particular resource per hour, on average. The probability that no requests are made in 45 minutes is:

A.
$e^{15}$
B.
$e^5$
C.
$1 - e^5$
D.
$1 - e^{-10}$

Question 45

In which of the following scheduling policies does context switching never take place?

A.
Round-robin
B.
First come first serve
C.
Shortest job first
D.
Both (B) and (C)

Question 46

In which of the following directory systems, it is possible to have multiple complete paths for a file, starting from the root directory?

A.
Single level directory
B.
Tree structural directory
C.
Two level directory
D.
Acyclic graph

Question 47

Suppose that a process is in ‘BLOCKED’ state waiting for some I/O service. When the service is completed, it goes to the:

A.
RUNNING state
B.
SUSPENDED state
C.
READY state
D.
TERMINATED state

Question 48

In a system that does not support swapping:

A.
The compiler normally binds symbolic addresses (variables) to relocate addresses
B.
The compiler normally binds symbolic addresses to physical addresses
C.
The loader binds relocatable addresses to physical addresses
D.
All of the above

Question 49

To obtain better memory utilization, dynamic loading is used. With dynamic loading, a routine is not loaded until it is called. For implementing dynamic loading:

A.
Special support from hardware is essential
B.
Special support from the operating system is essential
C.
Special support from both hardware and operating system are essential
D.
User programs can implement dynamic loading without any special support from the operating system or hardware

Question 50

Which of the following is true?

A.
The linkage editor is used to edit programs which have to be later linked together
B.
The linkage editor links object modules during compiling or assembling
C.
The linkage editor links object modules and resolves external references between them before loading
D.
The linkage editor resolves external references between the object modules during execution time

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