Important Questions and Answers for Class 11 Computer Science Chapter 1 Computer System 2025-26

Q1. Which component is considered the "brain" of the computer?

• (a) RAM
• (b) Hard Disk
• (c) CPU
• (d) Monitor

Answer: (c) CPU.

Q2. Which of the following is an example of secondary memory?

• (a) Cache Memory
• (b) Register
• (c) RAM
• (d) Pen Drive

Answer: (d) Pen Drive.

Q3. The operating system is classified as which type of software?

• (a) System Software
• (b) Application Software
• (c) Programming Tool
• (d) Customised Software

Answer: (a) System Software.

Q4. Which of the following best describes unstructured data?

• (a) Tabular attendance record
• (b) Data in a database
• (c) Audio file
• (d) HTML table

Answer: (c) Audio file.

2. Very Short Answer (VSA).

Q1. Define primary memory.

Answer: Primary memory is a computer’s main memory that stores data and instructions temporarily for quick access by the CPU. It mainly includes RAM and ROM.

Q2. What is the function of an input device?

Answer: An input device converts user data or commands into a digital format acceptable by the computer system, allowing the computer to receive instructions and information.

Q3. Mention one example of application software.

Answer: One example of application software is a web browser, which helps users access and view websites on the Internet.

Q4. What is a bit?

Answer: A bit is the smallest unit of memory in a computer, representing a binary digit—either 0 or 1.

3. Short Answer Questions.

Q1. Differentiate between volatile and non-volatile memory with examples.

Answer: Volatile memory, such as RAM, loses its data when power is lost, while non-volatile memory, like ROM or hard disks, retains data even when the computer is switched off. RAM is used for temporary data; ROM stores permanent instructions.

Q2. Explain the purpose of the Control Unit in a computer.

Answer: The Control Unit (CU) directs the execution of instructions by interpreting program commands, managing the sequence in which operations are performed, and overseeing data flow between memory, ALU, and input/output devices.

Q3. State any two differences between system software and application software.

Answer: System software manages and operates computer hardware (e.g., operating system), while application software helps users perform specific tasks, like word processing. Additionally, system software is essential for running the system; application software is optional.

Q4. Why are microcontrollers preferred in smart appliances?

Answer: Microcontrollers are compact, energy-efficient, and combine CPU, memory, and peripherals on a single chip. This makes them ideal for dedicated automatic tasks in smart appliances like microwaves or washing machines.

4. Long Answer Questions.

Q1. Describe the evolution of computing devices from Abacus to modern computers.

Answer: Computing devices began with the Abacus, a simple mechanical calculator for arithmetic. Later, the Analytical Engine introduced programmability. Pascaline, tabulating machines, and the Turing Machine contributed concepts like data storage and automation. The invention of transistors, followed by integrated circuits and microprocessors, revolutionized size and speed. Modern computers, like PCs, smartphones, and IoT gadgets, now perform complex data processing and automation.

1. Abacus: simple calculations.
2. Analytical Engine: programmability.
3. Transistors & ICs: smaller, faster devices.
4. Microprocessors & AI: modern computing.

Q2. Explain the functions of the operating system and its importance in a computer system.

Answer: The operating system (OS) manages computer hardware and software resources. It handles process management, memory allocation, file management, and device management. The OS offers user-friendly interfaces and secure access to applications. Its presence is vital for coordinating hardware, running programs smoothly, and ensuring overall reliability and usability of the computer.

1. Manages processes and scheduling.
2. Allocates primary memory.
3. Handles files and security.
4. Coordinates device drivers.

Q3. Discuss the types of data (structured, semi-structured, unstructured) with examples.

Answer: Structured data is organized in tables, like attendance records. Semi-structured data doesn't follow rigid tables but includes tags, such as HTML or CSV files. Unstructured data lacks a predefined format, including text documents, images, or audio. All types are crucial for computing applications and digital storage.

1. Structured: Student attendance table.
2. Semi-structured: HTML/CSS files.
3. Unstructured: Images, audio files.

Q4. True or False Questions.

Q1. RAM is a type of secondary memory.

Answer: False.

Q2. Device drivers are required for the proper functioning of hardware devices.

Answer: True.

Q3. The data bus is unidirectional.

Answer: False.

Q4. Microprocessors combine the CPU and peripherals on a single chip.

Answer: False.

5. Match the Following Questions.

Q1. Match the following.

Answer: 1 - A, 2 - B, 3 - C, 4 - D

Why Knowing Computer System Fundamentals Matters for Class 11 Students?

Learning about computer systems in Class 11 Computer Science Chapter 1 helps you understand the basic building blocks of technology. These important questions guide your preparation and improve your command of fundamental units like CPU, memory, and data.

Practising with computer system important questions sharpens your ability to answer both theory and application-based exams. You’ll feel more confident in CBSE assessments with well-explained question answers and simple explanations of structured and unstructured data types.

With this Class 11 Computer Science Chapter 1 question Answer PDF Download, you can revise anytime and build concepts step by step. This approach helps you score better and makes learning genuinely enjoyable and easier for your academic journey.