All questions of Achievers Section for Class 8 Exam

Understanding Computer Viruses
Computer viruses are malicious software programs designed to replicate and spread to other computers. Let's break down the statements to understand why option 'A' is correct.
Statement S1: A virus can replicate itself and spread to other computers.
- True: A key characteristic of a virus is its ability to replicate itself.
- Mechanism: Once a virus infects a host computer, it can attach itself to other programs or files, allowing it to spread to other systems, especially when shared through networks or removable storage devices.
Statement S2: A virus is always detectable by antivirus software.
- False: While antivirus software is designed to detect and remove viruses, it does not guarantee complete detection.
- Limitations: Some advanced viruses can evade detection through techniques like encryption, polymorphism, or simply by being new and not yet recognized by the antivirus database. Therefore, not all viruses are detectable at all times.
Conclusion
Given the analysis:
- Only S1 is correct because it accurately describes the self-replicating nature of viruses.
- S2 is incorrect due to the limitations of antivirus software in detecting every virus.
Thus, the correct answer is option 'A': Only S1 is correct. Understanding these aspects helps in better protection against computer viruses.

Understanding Binary Numbers
Binary numbers are fundamental in computer science and digital electronics. Let's analyze the two statements to understand why only S1 is correct.
S1: Binary numbers are represented using only 0s and 1s.
- Binary is a base-2 numbering system.
- It uses only two symbols: 0 and 1.
- Each digit in a binary number is called a "bit."
- For example, the binary number `1011` consists of four bits.
S2: Binary numbers are based on the base-10 numbering system.
- The base-10 system, also known as the decimal system, uses ten symbols (0-9).
- Binary is distinct from decimal as it operates on base-2.
- This means that binary counts differently than decimal, with each position representing a power of 2 rather than a power of 10.
Conclusion
- Only S1 is correct because it accurately describes the nature of binary numbers.
- S2 is incorrect as it mistakenly associates binary with the decimal system.
Thus, the correct answer is option 'A': Only S1 is correct.

Statement S1 is correct because the Internet is a global network of interconnected computers. Statement S2 is incorrect because the Internet is not owned by any single organization; it is a network of networks maintained by multiple organizations and entities.

Understanding the Hypervisor in Virtualization
The hypervisor is a crucial component in virtualization technology, primarily responsible for managing and allocating resources to virtual machines (VMs). Let's delve into its main functions.
Resource Management
- The hypervisor acts as a manager for the physical resources of the host machine, such as CPU, memory, and storage.
- It ensures that each VM gets the necessary resources to operate efficiently, preventing any single VM from monopolizing these resources.
Isolation of Virtual Machines
- By managing resources, the hypervisor maintains isolation between VMs, ensuring that they operate independently without interference.
- This isolation is critical for security and stability, allowing multiple operating systems to run on the same physical hardware.
Virtual Hardware Abstraction
- The hypervisor provides a layer of abstraction over the physical hardware, allowing VMs to interact with virtualized hardware rather than the actual physical components.
- This abstraction simplifies the process of creating and managing VMs, as users can deploy different operating systems without worrying about hardware compatibility.
Types of Hypervisors
- There are two main types of hypervisors: Type 1 (bare-metal) and Type 2 (hosted).
- Type 1 hypervisors run directly on the hardware, while Type 2 hypervisors operate on top of an existing operating system. Each type has its own advantages, depending on the use case.
Conclusion
In summary, the hypervisor's primary function is to manage and allocate resources to virtual machines effectively. This capability is essential for enabling virtualization, allowing multiple VMs to run on a single physical machine while ensuring performance, security, and stability.

The 'ping' command tests the reachability of a host on an IP network and measures the round-trip time for messages sent from the originating host to a destination computer. It is a diagnostic tool to ensure that a networked device is available and functioning.

Statement S1 is correct because cloud computing allows access to computing resources over the internet. Statement S2 is incorrect because cloud computing does not require physical presence near the data center; resources can be accessed remotely.

Statement S1 is correct because cybersecurity involves protecting computer systems from unauthorized access, use, disclosure, disruption, modification, or destruction. Statement S2 is incorrect because cybersecurity also involves protecting data and systems from various digital threats, not just physical theft of hardware.

Statement S1 is correct because an algorithm is a step-by-step procedure to solve a problem. Statement S2 is incorrect because an algorithm should be clear and unambiguous.

Statement S1 is correct because AI enables machines to perform tasks that typically require human intelligence, such as learning, reasoning, and problem-solving. Statement S2 is incorrect because AI is used in a wide range of applications beyond video games.

Statement S2 is correct because RAM (Random Access Memory) is used for temporary storage while a computer is running. Statement S1 is incorrect because RAM is volatile memory, meaning it loses its data when the computer is turned off.

Both statements are correct. An OS manages hardware resources and provides a user interface for interaction with the computer, making it possible for users to perform tasks and run applications.

In the context of hardware engineering, the term "board" typically refers to the motherboard, which is the main circuit board in a computer. Interconnection units called buses are part of the motherboard, but the term "board" generally does not specifically refer to them.