Computer Science/IT MCQs
Topic Notes: Computer Science/IT
MCQs and preparation resources for competitive exams, covering important concepts, past papers, and detailed explanations.
Plato
- Biography: Ancient Greek philosopher (427–347 BCE), student of Socrates and teacher of Aristotle, founder of the Academy in Athens.
- Important Ideas:
- Theory of Forms
- Philosopher-King
- Ideal State
171
The hexadecimal ASCII value for a space character is 20. What is its decimal value?
Answer:
32
To convert (20)₁₆ to decimal: (2 \* 16¹) + (0 \* 16⁰) = 32 + 0 = 32.
172
Boolean algebra is the mathematics of:
Answer:
Logical values (true/false)
Developed by George Boole, it provides a formal system for manipulating logical statements and variables that can only have two states: true (1) and false (0).
173
A logic gate that acts as a controlled switch, passing the input signal to the output only when a control signal is high, is a(n):
Answer:
AND gate
If you consider one input as the "signal" and the other as the "control", the output will only be equal to the signal when the control is 1. If the control is 0, the output is always 0, effectively blocking the signal.
174
What is the main difference between UTF-8 and UTF-16?
Answer:
UTF-8 uses 8-bit code units, while UTF-16 uses 16-bit code units
The "8" and "16" refer to the size of the basic block (code unit) used. UTF-8 builds characters from one to four 8-bit blocks (bytes). UTF-16 builds characters from one or two 16-bit blocks.
175
How is the decimal number 100 represented in hexadecimal?
Answer:
(64)₁₆
100 / 16 = 6 with a remainder of 4. The result is 6. Reading from bottom to top gives (64)₁₆.
176
What was the primary limitation of the ASCII character set?
Answer:
It could not represent characters from languages other than English
ASCII was designed for English, containing only the basic Latin alphabet, numbers, and common symbols. It lacked the capacity for accented characters, non-Latin scripts, and various symbols used in other languages.
177
Which method is used to convert from a base-B number to a decimal number?
Answer:
Sum the products of each digit and its positional weight (power of B)
This is the fundamental definition of a positional number system. Each digit's value is multiplied by B raised to the power of its position, and all products are summed.
178
The number system we use for counting in our daily lives is:
Answer:
Decimal
The decimal (base-10) system is the standard system for denoting integers and non-integer numbers in everyday life.
179
What is the decimal equivalent of the hexadecimal number (11)₁₆?
Answer:
17
To convert a hexadecimal number to its decimal equivalent, each digit is multiplied by a power of 16, corresponding to its position, and the results are summed.
For the hexadecimal number (11)₁₆:
- The rightmost digit '1' is in the 16⁰ (units) place.
- The leftmost digit '1' is in the 16¹ (sixteens) place.
Calculation:
(1 * 16¹) + (1 * 16⁰)
= (1 * 16) + (1 * 1)
= 16 + 1
= 17
Therefore, the decimal equivalent of (11)₁₆ is 17.
180
Which of the following is a key characteristic of a positional number system?
Answer:
The value of a digit depends on its position within the number
In a positional system, the position of a digit determines its value. For example, in the number 555, each '5' has a different value (500, 50, and 5) because of its position.