I85PREP
⌘ K
RSMSSB Computor study materials
RSMSSB Computor study resources

RSMSSB Computor practice questions

One question at a time. Build your RSMSSB Computor understanding.

First 50 of 200 questions. Each one lists the choices, the correct answer, and an explanation. The checker at the top of this page saves progress in this browser when it is available.

Continue in the practice tool above to load more questions, 50 at a time.

Question 1Computer Fundamentals and Basics

In a computer system, which component is directly responsible for carrying out arithmetic operations such as addition and comparison of two binary numbers?

  1. Arithmetic Logic Unit Correct answer.
  2. Instruction Register
  3. Control Unit
  4. Main Memory

Explanation

The Arithmetic Logic Unit (ALU) is the part of the CPU that performs arithmetic operations like addition, subtraction and logical comparisons. The control unit only directs and coordinates operations, while memory stores data and the instruction register merely holds the current instruction.

Question 2Computer Fundamentals and Basics

A file on a disk is stored as a contiguous sequence of 4 KB blocks. Which term describes the smallest addressable unit that the operating system can read from or write to the disk in one operation?

  1. Nibble
  2. Word
  3. Bit
  4. Block Correct answer.

Explanation

Disk storage is organised into blocks (also called sectors or clusters at higher levels), and the operating system transfers data in whole blocks rather than individual bits or bytes. A bit is a single binary digit and a nibble is four bits, both far too small to be a disk transfer unit.

Question 3Computer Fundamentals and Basics

Which number system uses exactly sixteen distinct digit symbols and is commonly used as shorthand for binary values in computing?

  1. Binary
  2. Octal
  3. Decimal
  4. Hexadecimal Correct answer.

Explanation

Hexadecimal is base 16, using digits 0-9 plus letters A-F, and each hex digit maps neatly to four binary bits. Octal uses eight symbols and binary uses only two, so neither matches the description.

Question 4Computer Fundamentals and Basics

What is the decimal value of the binary number 1011?

  1. 13
  2. 11 Correct answer.
  3. 15
  4. 9

Explanation

Evaluating place values from left to right gives 1x8 + 0x4 + 1x2 + 1x1, which equals 11. Each position corresponds to a power of two starting at 2^0 on the right.

Question 5Computer Fundamentals and Basics

Which of the following is an example of system software rather than application software?

  1. A web browser
  2. A photo editor
  3. A spreadsheet program
  4. An operating system kernel Correct answer.

Explanation

System software manages hardware and provides a platform for other programs; the operating system kernel is the core example of this category. Spreadsheets, browsers and photo editors are application software written to perform user-facing tasks.

Question 6Computer Fundamentals and Basics

In the context of computer fundamentals, what does the term 'firmware' most accurately describe?

  1. A utility that compresses files before storage
  2. A driver installed by the user after buying a printer
  3. Software permanently stored in read-only memory on a hardware device Correct answer.
  4. A temporary copy of a program held in RAM during execution

Explanation

Firmware is program code embedded in non-volatile memory such as ROM or flash on a device, controlling its low-level operation. It persists across power cycles and is not the same as a transient RAM copy or a user-installed driver.

Question 7Computer Fundamentals and Basics

Which unit of storage is equal to 1024 megabytes in the binary convention commonly used in computer science?

  1. 1 kilobyte
  2. 1 terabyte
  3. 1 petabyte
  4. 1 gigabyte Correct answer.

Explanation

In the binary convention, each storage unit is 1024 times the previous one, so 1024 megabytes make one gigabyte. A kilobyte is 1024 bytes, a terabyte is 1024 gigabytes and a petabyte is 1024 terabytes.

Question 8Computer Fundamentals and Basics

Which input device converts a physical document into a digital image file that can be stored on a computer?

  1. Scanner Correct answer.
  2. Light pen
  3. Digitizer tablet
  4. Plotter

Explanation

A scanner optically reads a printed page and produces a digital image of it for storage or editing. A plotter is an output device, while a digitizer tablet and light pen are used for positional input rather than document capture.

Question 9Computer Fundamentals and Basics

A user converts the decimal number 45 into binary. Which result is correct?

  1. 101011
  2. 101101 Correct answer.
  3. 111001
  4. 110101

Explanation

Dividing 45 repeatedly by 2 gives remainders 1,0,1,1,0,1 read in reverse, producing 101101. Checking the value: 32 + 8 + 4 + 1 equals 45.

Question 10Computer Fundamentals and Basics

In a computer, which memory is volatile and loses its contents when power is switched off, yet provides the working space the CPU uses during program execution?

  1. RAM Correct answer.
  2. Hard disk
  3. ROM
  4. Flash drive

Explanation

RAM is volatile read/write memory that holds programs and data currently in use, and its contents vanish when power is removed. ROM, hard disks and flash drives all retain data without power.

Question 11Computer Fundamentals and Basics

What is the primary function of an operating system in a computer system?

  1. To translate high-level languages into assembly language
  2. To compile source code into machine instructions
  3. To manage hardware resources and provide services to application programs Correct answer.
  4. To design and edit graphical images

Explanation

An operating system acts as an intermediary between hardware and applications, managing memory, processor time, files and devices while offering services through system calls. Compilers and image editors are separate programs that run on top of the operating system.

Question 12Computer Fundamentals and Basics

Which of the following best describes a compiler as opposed to an interpreter?

  1. It executes the source program one statement at a time without producing an object file
  2. It links separately compiled object files into a single executable
  3. It converts assembly language mnemonics into machine code
  4. It translates the entire program into machine code before execution begins Correct answer.

Explanation

A compiler processes the whole source program and produces an object or executable file before the program runs. An interpreter translates and executes statement by statement, while an assembler handles mnemonics and a linker joins object files.

Question 13Computer Fundamentals and Basics

Which logic gate produces an output of 1 only when all of its inputs are 1?

  1. OR gate
  2. XOR gate
  3. AND gate Correct answer.
  4. NOT gate

Explanation

An AND gate outputs 1 only when every input is 1; a single 0 input forces the output to 0. OR outputs 1 if any input is 1, NOT inverts, and XOR outputs 1 only for an odd number of 1 inputs.

Question 14Computer Fundamentals and Basics

A user wants to move a file from one folder to another on the same disk. Which operation does the operating system perform?

  1. Recompresses the file into the destination folder
  2. Copies the file contents and deletes the original
  3. Updates the directory entry to point to the new location Correct answer.
  4. Converts the file to a different format before moving

Explanation

Moving a file within the same disk volume only requires updating directory metadata to reference the new path, so the data blocks stay in place. Copying and deleting is what happens when moving across different volumes.

Question 15Computer Fundamentals and Basics

What is the hexadecimal equivalent of the binary number 11111010?

  1. EA
  2. AF
  3. FA Correct answer.
  4. F5

Explanation

Grouping the binary digits into nibbles gives 1111 and 1010, which are F and A in hexadecimal, so the result is FA. Each hex digit corresponds to four consecutive binary bits.

Question 16Computer Fundamentals and Basics

Which of the following correctly lists the stages of the instruction cycle in the order they occur?

  1. Store, decode, fetch, execute
  2. Decode, fetch, execute, store
  3. Fetch, decode, execute, store Correct answer.
  4. Execute, fetch, decode, store

Explanation

The CPU first fetches the instruction from memory, then decodes it to determine the operation, executes it, and finally stores any result back to memory or registers. This sequence repeats for each instruction.

Question 17Computer Fundamentals and Basics

A user types a command in a command-line interface. Which component of the operating system interprets and executes that command?

  1. Interrupt handler
  2. File allocation table
  3. Command interpreter Correct answer.
  4. Device driver

Explanation

The command interpreter (shell) reads the typed command, interprets its meaning and invokes the appropriate program or system service. Device drivers control hardware, file allocation tables track disk usage and interrupt handlers respond to hardware events.

Question 18Computer Fundamentals and Basics

Which of the following is a characteristic of primary memory but not of secondary storage?

  1. It is directly accessed by the CPU for current processing Correct answer.
  2. It retains data permanently without power
  3. It stores backup copies of files
  4. It has a much larger capacity than main memory

Explanation

Primary memory such as RAM is directly addressable by the CPU and holds the instructions and data currently in use. Secondary storage is slower, non-volatile and much larger, but it is not directly accessed at processing speed.

Question 19Computer Fundamentals and Basics

What is the result of adding the binary numbers 1011 and 0110?

  1. 10101
  2. 10011
  3. 10001 Correct answer.
  4. 11001

Explanation

Adding column by column from the right: 1+0=1, 1+1=0 carry 1, 0+1+1=0 carry 1, and 1+0+1=0 carry 1, giving 10001, which equals 17 in decimal. Checking decimals, 11 plus 6 equals 17.

Question 20Computer Fundamentals and Basics

Which of the following statements about the terms 'bit' and 'byte' is correct?

  1. One bit contains four bytes and is called a nibble
  2. One bit contains eight bytes and can represent 256 distinct values
  3. One byte contains eight bits and can represent 256 distinct values Correct answer.
  4. One byte contains sixteen bits and can represent 1024 distinct values

Explanation

A byte is conventionally eight bits, so it has 2^8, that is 256, distinct bit patterns. A bit is a single binary digit and therefore the smaller unit, not the larger one.

Question 21Computer Fundamentals and Basics

In a computer's memory, which addressing scheme allows a program to refer to memory locations by symbolic names that are resolved to actual addresses during compilation or loading?

  1. Symbolic addressing Correct answer.
  2. Physical addressing
  3. Direct addressing
  4. Immediate addressing

Explanation

Symbolic addressing lets a programmer use names for variables and labels, which the assembler or compiler then translates into real addresses. Physical and direct addressing refer to actual or effective addresses, while immediate addressing embeds the operand value in the instruction itself.

Question 22Computer Fundamentals and Basics

A cache memory of 8 KB is placed between a CPU and main memory. Which statement best explains why this arrangement improves performance?

  1. It increases the total capacity of main memory available to programs
  2. It permanently stores the operating system so that it never needs reloading
  3. It holds frequently accessed instructions and data so that average access time is reduced Correct answer.
  4. It converts machine code into assembly language before execution

Explanation

A cache exploits locality of reference by keeping recently or frequently used blocks close to the CPU, so many accesses complete faster than a main-memory access. It does not enlarge main memory, permanently store the operating system, or perform any translation.

Question 23Computer Fundamentals and Basics

Which of the following best distinguishes a multiprogramming operating system from a multiprocessing system?

  1. Multiprogramming keeps several programs in memory and switches the CPU among them, whereas multiprocessing uses two or more CPUs executing simultaneously Correct answer.
  2. Multiprogramming uses two or more CPUs simultaneously, whereas multiprocessing keeps several programs in memory and switches among them
  3. Multiprogramming requires a network of computers, whereas multiprocessing requires only a single CPU
  4. Multiprogramming and multiprocessing are identical terms describing time-sharing on a single processor

Explanation

Multiprogramming increases CPU utilisation on a single processor by interleaving several resident programs, switching when one waits for I/O. Multiprocessing instead involves multiple processors executing instructions truly in parallel. The two concepts address different hardware and scheduling situations.

Question 24Computer Fundamentals and Basics

A 12-bit binary number is used to represent signed integers in two's complement form. What is the range of values that can be represented?

  1. -2047 to 2047
  2. -2048 to 2047 Correct answer.
  3. 0 to 4095
  4. -4096 to 4095

Explanation

With n bits in two's complement, the range is -2^(n-1) to 2^(n-1) - 1. For n equal to 12 this gives -2048 to 2047, a total of 4096 distinct values.

Question 25Computer Fundamentals and Basics

Which statement correctly describes the role of the program counter during instruction execution?

  1. It holds the address of the next instruction to be fetched Correct answer.
  2. It counts the number of clock cycles used by the program
  3. It stores the result of the most recent arithmetic operation
  4. It contains the opcode of the instruction being executed

Explanation

The program counter (instruction pointer) holds the memory address of the next instruction, and it is incremented or set to a branch target as execution proceeds. Results of operations go to the accumulator or general registers, and opcodes are held in the instruction register.

Question 26Computer Fundamentals and Basics

In a computer system, which component is responsible for performing arithmetic operations such as addition and comparison of two numbers?

  1. The hard disk controller
  2. The control unit inside the CPU
  3. The Arithmetic Logic Unit inside the CPU Correct answer.
  4. The main memory module

Explanation

The Arithmetic Logic Unit (ALU) is the part of the processor that carries out arithmetic and logical operations on data held in registers. The control unit coordinates instruction flow but does not itself add numbers, and storage devices only hold data.

Question 27Computer Fundamentals and Basics

A monitor that shows output to a user is best classified in the computer system as which of the following?

  1. A processing device
  2. A storage device
  3. An output device Correct answer.
  4. An input device

Explanation

An output device presents processed results from the computer to the user, and a monitor displays text and graphics for that purpose. It does not send data into the system, compute, or retain files permanently.

Question 28Computer Fundamentals and Basics

In a computer, what is the smallest addressable unit of memory that a program can normally read or write in one operation?

  1. A bit
  2. A word
  3. A nibble
  4. A byte Correct answer.

Explanation

Memory is addressed in bytes on mainstream computer architectures, so a byte is the smallest unit a program can individually access. A bit is smaller but is not independently addressed, and a word is larger than a byte.

Question 29Computer Fundamentals and Basics

Which of the following best describes the function of a computer's control unit?

  1. It directs the flow of data and coordinates the other units by decoding instructions Correct answer.
  2. It converts analogue signals into digital values
  3. It supplies electrical power to the motherboard
  4. It stores the program instructions permanently

Explanation

The control unit fetches and decodes each instruction and then generates the signals that tell the ALU, registers and memory what to do. Permanent storage, signal conversion and power delivery belong to other components.

Question 30Computer Fundamentals and Basics

Which of the following file extensions typically identifies an executable program file on a Windows system?

  1. .jpg
  2. .exe Correct answer.
  3. .txt
  4. .csv

Explanation

Windows uses the .exe extension for executable program files that the operating system can load and run. The other extensions denote plain text, an image and comma-separated data, none of which are runnable programs.

Question 31Computer Fundamentals and Basics

Which of the following is a task that a spreadsheet application performs on numeric data?

  1. Resolving domain names to IP addresses
  2. Formatting a disk partition
  3. Compiling source code into machine code
  4. Calculating totals using built-in formulas Correct answer.

Explanation

Spreadsheet software is designed to organise numbers in cells and compute results through formulas and functions such as SUM. Compilation, disk formatting and name resolution are tasks of entirely different software.

Question 32Computer Fundamentals and Basics

Which of the following correctly states the relationship between a kilobyte and a byte in the decimal (SI) convention?

  1. 1 kilobyte equals 100 bytes
  2. 1 kilobyte equals 1000 bytes Correct answer.
  3. 1 kilobyte equals 8 bytes
  4. 1 kilobyte equals 1024 bytes

Explanation

In the decimal SI convention the prefix kilo means one thousand, so one kilobyte is 1000 bytes. The value 1024 belongs to the binary convention, often written kibibyte, while 8 bytes is merely the size of a 64-bit word.

Question 33Computer Fundamentals and Basics

A technician needs to store a 3 GB video file on a device. Which of the following media can hold the file while still being a form of secondary storage?

  1. A 512 MB RAM module
  2. A 256 KB cache memory
  3. A 4 MB ROM chip
  4. An 8 GB USB pen drive Correct answer.

Explanation

Secondary storage retains data without power, and an 8 GB pen drive has ample capacity for a 3 GB file. RAM, cache and ROM are primary or firmware memory and are too small or unsuitable for holding a large user file.

Question 34Computer Fundamentals and Basics

A user wants to keep a copy of a document in the same folder under a new name while retaining the original. Which file operation accomplishes this?

  1. Copy and paste Correct answer.
  2. Delete
  3. Rename
  4. Move

Explanation

Copying the file and pasting it in the same folder creates an additional file with identical content, which can then be renamed. Move relocates the only copy, rename changes the name of the existing file, and delete removes it.

Question 35Computer Fundamentals and Basics

What is the decimal value of the binary number 11001?

  1. 24
  2. 25 Correct answer.
  3. 31
  4. 17

Explanation

Reading place values from the right, 11001 equals 1x16 + 1x8 + 0x4 + 0x2 + 1x1, which totals 25. The other options result from misreading the place values or dropping a set bit.

Question 36Computer Fundamentals and Basics

A logic circuit must output 1 when at least one of its two inputs is 1, and output 0 only when both inputs are 0. Which gate implements this?

  1. NOT gate
  2. AND gate
  3. NAND gate
  4. OR gate Correct answer.

Explanation

The OR gate outputs 1 whenever any input is 1 and outputs 0 only when all inputs are 0, which matches the stated behaviour. AND requires all inputs to be 1, NAND inverts the AND result, and NOT accepts a single input.

Question 37Computer Fundamentals and Basics

Which of the following correctly pairs a primary memory with the reason it is described as volatile?

  1. RAM, because it loses its contents when power is removed Correct answer.
  2. ROM, because its contents can be rewritten
  3. Hard disk, because it stores data magnetically
  4. Cache, because it is smaller than the main memory

Explanation

Volatility means the stored contents disappear when power is switched off, and RAM behaves exactly this way. Hard disks are non-volatile secondary storage, ROM is non-volatile, and small size does not make cache volatile.

Question 38Computer Fundamentals and Basics

A computer has 4 GB of RAM and runs several programs at once. Which function of the operating system allows each program to believe it has its own continuous memory?

  1. Disk defragmentation
  2. Print spooling
  3. File compression
  4. Virtual memory management with address translation Correct answer.

Explanation

The operating system maps each program's virtual addresses onto physical frames, giving every process the illusion of a private, contiguous address space. Compression, defragmentation and spooling concern files, disks and printers respectively, not address spaces.

Question 39Computer Fundamentals and Basics

Which of the following statements about the ASCII character encoding is correct?

  1. It represents every Unicode character using 16 bits
  2. It assigns a unique 7-bit code to each of 128 characters Correct answer.
  3. It stores the colour of each pixel on a screen
  4. It encodes only digits and arithmetic operators

Explanation

Standard ASCII uses seven bits, giving 128 distinct codes for letters, digits, punctuation and control characters. Unicode is the broader standard, and pixel colour is a graphics concern rather than character encoding.

Question 40Computer Fundamentals and Basics

A company wants each employee to have a unique numeric code from 1 to 500. What is the minimum number of bits needed to store any such code?

  1. 7 bits
  2. 10 bits
  3. 9 bits Correct answer.
  4. 8 bits

Explanation

With n bits, 2^n distinct values can be represented. Seven bits give 128 values and eight bits give 256, both insufficient, while nine bits give 512 values, enough to cover codes up to 500.

Question 41Computer Fundamentals and Basics

Which of the following best explains why a solid-state drive generally opens files faster than a magnetic hard disk?

  1. It compresses every file automatically
  2. It stores data in volatile memory that is faster than disk platters
  3. It has no moving mechanical parts, so data access does not wait for a rotating platter Correct answer.
  4. It uses a larger block size than a hard disk

Explanation

An SSD stores data in flash memory cells addressed electronically, so there is no seek time or rotational latency. Volatility, block size and automatic compression are not the reasons for its speed advantage.

Question 42Computer Fundamentals and Basics

A program is described as using a high-level language. Which statement best characterises such a language?

  1. It is executed directly by the hardware without any translation
  2. It is written using English-like statements that must be translated before execution Correct answer.
  3. It uses mnemonics that map one-to-one onto machine instructions
  4. It consists only of binary 0 and 1 values

Explanation

High-level languages use readable constructs such as variables, loops and functions that are independent of the hardware, so a compiler or interpreter must translate them. Mnemonics describe assembly language, and binary is machine language.

Question 43Computer Fundamentals and Basics

A user presses a key on the keyboard. Which sequence correctly describes how the character reaches the screen?

  1. Keyboard sends a code to the CPU, the operating system processes it, and the display adapter renders it on the monitor Correct answer.
  2. The hard disk detects the keypress and writes the character to a file
  3. The monitor reads the key directly and displays the character
  4. The printer driver converts the keypress into a screen character

Explanation

The keyboard controller sends a scan code to the system, the CPU and operating system interpret it, and the display adapter outputs the resulting character to the monitor. Peripherals do not bypass the processor, and disks and printer drivers play no part in this path.

Question 44Computer Fundamentals and Basics

Which of the following describes the purpose of a device driver in an operating system?

  1. To convert source code into an executable program
  2. To translate between the operating system and a specific hardware device Correct answer.
  3. To allocate disk space to files
  4. To manage user login passwords

Explanation

A device driver is software that knows the commands and protocols of one particular piece of hardware and presents a standard interface to the operating system. Compilation, password management and disk allocation are handled by other system software.

Question 45Computer Fundamentals and Basics

A programmer needs a storage location in the CPU that holds the operand currently being processed by an arithmetic instruction. Which register serves this purpose?

  1. The accumulator Correct answer.
  2. The memory address register
  3. The program counter
  4. The instruction register

Explanation

The accumulator holds the data on which the ALU is currently operating and often receives the result. The program counter holds the next instruction address, the instruction register holds the fetched instruction, and the memory address register holds an address.

Question 46Computer Fundamentals and Basics

A file system stores a file across several non-contiguous disk blocks. Which structure allows the operating system to locate all the blocks of that file?

  1. The cache tag array
  2. The boot sector that loads the operating system
  3. The printer spooler queue
  4. The file allocation table or index node that records the block addresses Correct answer.

Explanation

File systems maintain metadata such as a FAT or an inode listing the blocks belonging to each file, which permits non-contiguous allocation. The boot sector starts the system, the spooler handles printing, and cache tags concern memory caching.

Question 47Computer Fundamentals and Basics

An 8-bit register currently holds 11111111. If 1 is added to it and the result is kept in 8 bits, what value appears in the register?

  1. 11111110
  2. 00000001
  3. 100000000
  4. 00000000 Correct answer.

Explanation

Adding 1 to 11111111 produces 100000000, but an 8-bit register cannot hold the ninth bit, so it is discarded and the register shows 00000000. This wraparound is the overflow that sets the carry flag.

Question 48Computer Fundamentals and Basics

A process is in the ready state. Which event moves it to the running state in a typical operating system?

  1. The process issues a request for disk input
  2. The process is swapped out to secondary storage
  3. The process finishes its execution
  4. The scheduler selects it and assigns the CPU to it Correct answer.

Explanation

A ready process is waiting only for the processor, so the scheduler dispatches it to the CPU and it becomes running. Requesting input, terminating and being swapped out move a process away from the running state.

Question 49Computer Fundamentals and Basics

Why does a computer system use the two's complement representation for signed integers?

  1. It lets subtraction be performed by addition of the complement, simplifying the ALU Correct answer.
  2. It removes the need for a sign bit entirely
  3. It guarantees that overflow can never occur
  4. It doubles the number of values that can be stored in a given number of bits

Explanation

In two's complement, a - b is computed as a plus the complement of b, so one adder circuit handles both addition and subtraction. The representation does not increase the count of values, does not eliminate the sign bit, and cannot prevent overflow.

Question 50Computer Fundamentals and Basics

A computer has a small fast cache between the CPU and main memory. Which principle explains why this arrangement usually speeds up program execution?

  1. Locality of reference, because recently and frequently used data is likely to be needed again Correct answer.
  2. Compression, because cached data is stored in fewer bytes
  3. Virtualisation, because cache emulates a larger disk
  4. Parallelism, because cache adds extra processor cores

Explanation

Programs tend to reuse the same instructions and data in short periods, a property called locality of reference, so keeping those items in fast cache avoids slow main-memory accesses. Compression, extra cores and disk emulation are unrelated to cache operation.