CS Free MCQ Bank

[ Option A ]

Memory storage refers to devices or media used to store data and programs in a computer.

• Primary memory (Volatile) is directly accessible by the CPU and loses its data when the power is turned off, examples include RAM and cache. 
• Secondary memory (Non-Volatile) stores data permanently, such as hard disks, SSDs, and optical discs.
• Tertiary and offline storage is used for backups and large-scale data storage, including tape drives and external hard drives.

Storage units are used to measure the amount of data in a computer, starting from the smallest unit, a bit, to larger units like Byte, Kilobyte (KB), Megabyte (MB), Gigabyte (GB), and Terabyte (TB).

• Bit → Byte → KB → MB → GB → TB → PB → EB → ZB → YB. Trick “Bharat Ke Modi Gaye Taj Pe Ek Zaruri Yatra”.

[ Option A ]

[ Option B ]

Storage units are used to measure the amount of data in a computer, starting from the smallest unit, a bit, to larger units like byte, kilobyte (KB), megabyte (MB), gigabyte (GB), and terabyte (TB).

• Bit → Byte → KB → MB → GB → TB → PB → EB → ZB → YB. Trick “Bharat Ke Modi Gaye Taj Pe Ek Zaruri Yatra”.

[ Option B ]

CSA stands for Computer Speed Addition. It refers to techniques used in computer arithmetic to perform addition faster, often by reducing the time required to handle carries during binary addition.
By designing circuits that can process sums and carries efficiently, computers can speed up arithmetic operations, which is critical in processors and digital systems.

[ Option A ]

The repeated division method by 2 is used to convert a decimal (base 10) number into a binary (base 2) number.
Steps:
1. Divide the decimal number by 2.
2. Record the remainder.
3. Use the quotient for the next division by 2.
4. Repeat until the quotient becomes 0.
5. The binary number is formed by reading the remainders from bottom to top.

[ Option B ]

[ Option C ]

To convert the hexadecimal number (1F.01B)₁₆ into its decimal equivalent, we first separate it into the integer part (1F) and the fractional part (.01B).

In integer part conversion, each digit is multiplied by 16 raised to the power of its position from right to left, starting with 0.
(1F)₁₆ = 1⋅16¹+F⋅16⁰ = 16+15 = 31
In fractional part conversion, each digit after the hexadecimal point is multiplied by 16 raised to a negative power corresponding to its position.
0⋅16⁻¹+1⋅16⁻²+B⋅16⁻³ = 0 + 0.00390625 + 0.002685546875 = 006591796875 ≈ 0.0065918
After combining integer and fractional parts, 31 + 0.0065918 = 31.0065918
 

[ Option D ]

Data in computers is stored in binary form as bits (0 or 1), which are the smallest possible units. The hierarchy is starting from Bits → Nibble → Byte → KB → MB → GB → TB → PB.

However, among the given options (KB, GB, Byte, Nibble), the smallest unit is the Nibble (4 bits), which is smaller than a byte (8 bits).

[ Option D ]

Storage units are used to measure the amount of data in a computer, starting from the smallest unit, a bit, to larger units like byte, kilobyte (KB), megabyte (MB), gigabyte (GB), and terabyte (TB).

• Bit → Byte → KB → MB → GB → TB → PB → EB → ZB → YB. Trick “Bharat Ke Modi Gaye Taj Pe Ek Zaruri Yatra”.

[ Option A ]

To quickly convert a number from octal to hexadecimal, first convert the octal number into binary by replacing each octal digit with its 3-bit binary equivalent. Then, group the binary digits into 4-bit groups starting from the right. Finally, convert each 4-bit group into its hexadecimal equivalent. 
For example, to convert 356₈to hexadecimal:

• Convert each octal digit to 3-bit binary: 3 → 011, 5 → 101, 6 → 110 → 011101110₂
• Group into 4-bit sections from the right: 1110 1110₂
• Convert each group to hexadecimal: 1110 → E, 1110 → E → EE₁₆

So, 356₈ = EE₁₆.

[ Option A ]

The smallest unit of data in a computer is a bit, which stands for binary digit. A bit can hold only one of two values: 0 or 1.

[ Option C ]

In computer storage, memory is measured in bytes, and larger units are multiples of bytes:

[ Option C ]

Binary Coded Decimal (BCD) is a method of representing each decimal digit (0 to 9) using a fixed number of binary bits. Each decimal digit is encoded using 4 bits, which is exactly half a byte and commonly called a nibble.

[ Option C ]

The hexadecimal number system is a base-16 positional numeral system used widely in computing and digital electronics. It uses 16 distinct symbols to represent values from 0 to 15:

• The first 10 symbols are the decimal digits 0 to 9.
• The next 6 symbols are the letters A to F, where value of A is 10 and F is 15.

[ Option C ]

To find the binary number that, when divided by 11 (binary), gives a quotient of 10 (binary), we first convert the binary numbers to decimal for easier calculation. The divisor 11 in binary is equal to 3 in decimal, and the quotient 10 in binary is equal to 2 in decimal.

Using the formula for division, Dividend = Divisor × Quotient + Remainder, and assuming the remainder is zero, we calculate the dividend as 3 × 2 = 6. Converting 6 back into binary gives 110.

Therefore, dividing the binary number 110 by 11 results in a quotient of 10, making 110 the correct binary number for this question.

[ Option A ]

Storage units are used to measure the amount of data in a computer, starting from the smallest unit, a bit, to larger units like byte, kilobyte (KB), megabyte (MB), gigabyte (GB), and terabyte (TB).

• Bit → Byte → KB → MB → GB → TB → PB → EB → ZB → YB. Trick “Bharat Ke Modi Gaye Taj Pe Ek Zaruri Yatra”.

[ Option D ]

To convert a binary number to hexadecimal, group the binary digits in sets of 4 (adding leading zeros if necessary), then convert each group to its hexadecimal equivalent and combine.

Step 1:
Group the binary number into 4-bit groups from right to left:
111111000101101001
Since the leftmost group has only 2 bits, we can pad with 2 leading zeros:
0011 1111 0001 0110 1001
Step 2:
Convert each 4-bit group to hexadecimal:

• 0011 : 3
• 1111 : F
• 0001 : 1
• 0110 : 6
• 1001 : 9

Combine the hexadecimal digits:
(111111000101101001)₂ = (3F169)₁₆
 

[ Option C ]

To convert the binary number (1110100.0100111)₂ into octal, we divide the digits into groups of three bits each, starting from the binary point. 
For the integer part, grouping (1110100)₂ as (001 110 100) gives octal digits 1, 6, and 4 respectively, forming (164)₈. 
For the fractional part, grouping (0100111)₂ as (010 011 100) gives octal digits 2, 3, and 4, forming (.234)₈. 
Thus, the octal equivalent of (1110100.0100111)₂ is (164.234)₈.

[ Option C ]

BCD (Binary-Coded Decimal) is a way of representing decimal digits (0–9) in binary form. Each decimal digit is represented by 4 bits.

Add the two BCD numbers like normal binary addition: 0010 (2) + 0011 (3) = 0101 (5). Since the sum (5 → 0101) is less than 10 (not greater than 9 (1001)) , no correction is needed. If the sum is greater than 9 (1001), add 6 (0110) to correct it. Consider the below example:

[ Option A ]

We need to convert binary number (101110)₂ into octal (base 8). Rule for Binary to Octal Conversion is:

• Group binary digits into 3 bits (from right to left).
• Convert each 3-bit group into its octal equivalent.

Here, (101110)₂ can be grouped as 101 and 110. The binary group 101 equals 5 in decimal, and 110 equals 6 in decimal, which gives us the octal number (56)₈.

[ Option B ]

Each digit after the binary point represents a negative power of 2. By summing these values, we convert the binary fraction to its decimal equivalent. To convert a binary fraction to decimal, use the formula:

0.b1b2b3b4 = b1×2⁻¹ + b2×2⁻² + b3×2⁻³ + b4×2⁻⁴

Given: 
(0.1011)2 =1×2⁻¹ + 0×2⁻² + 1×2⁻³ + 1×2⁻⁴
=0.5+0+0.125+0.0625
=0.6875
So, (0.1011)₂ = (0.6875)₁₀
 

[ Option A ]

Storage units are used to measure the amount of data in a computer, starting from the smallest unit, a bit, to larger units like byte, kilobyte (KB), megabyte (MB), gigabyte (GB), and terabyte (TB).

• Bit → Byte → KB → MB → GB → TB → PB → EB → ZB → YB.

[ Option B ]

Digital Signals are discrete signals that represent information using distinct values, often in binary form (0s and 1s). They are generated by digital modulation techniques and are used in computers, digital communication, and networking devices.

Unlike Analog Signals, which are continuous, digital signals are less prone to noise and distortion, making them more reliable for data transmission.

[ Option D ]

[ Option D ]

The binary fraction (0.10101)₂ is converted to decimal by multiplying each digit with 2⁻ⁿ, where n is the position after the decimal point. Thus, it becomes 1×2⁻¹ + 0×2⁻² + 1×2⁻³ + 0×2⁻⁴ + 1×2⁻⁵. This equals 0.5 + 0 + 0.125 + 0 + 0.03125 = 0.65625. Therefore, the decimal equivalent of (0.10101)₂ is (0.65625)₁₀.

[ Option B ]

[ Option A ]

Analog Signals represent continuous data and real-world phenomena such as smell, speech, temperature, or pressure that vary smoothly.
Digital Signals are discrete and represent data in binary form, such as scanning, which converts images or documents into digital data.

[ Option B ]

[ Option D ]

BCD (Binary-Coded Decimal) represents decimal digits 0 to 9 using 4-bit binary codes.

🔶 BCD Valid Range: 0000 to 1001

🔶 1011 = 11 (which is not a valid decimal digit in BCD)

[ Option B ]

[ Option A ]

[ Option B ]

The octal number system is a base-8 number system, which means it uses 8 digits: 0, 1, 2, 3, 4, 5, 6, and 7. Each place value in octal represents a power of 8.

[ Option B ]

A Modem (Modulator-Demodulator) is a device that allows computers to communicate over telephone lines or other analog transmission media.

• The data originates as digital (0s and 1s) form from the computer.
• The modem converts this digital data into analog signals suitable for transmission over traditional telephone lines or other analog communication media.
• At the receiving end, the modem converts the analog signals back into digital data for the receiver.

This process is called Modulation (Digital to Analog) and Demodulation (Analog to Digital), which is why the device is called a MODEM (Modulator-Demodulator).