Class 10 Computer Science Chapter 1 Test 3: Operating System – Structure & Services | Punjab Board 2027

(PART - I)

1. i)
   How operating system works?.

   Ans: The OS loads when the computer starts, manages the CPU, memory and devices, runs programs, and passes user and application requests to the hardware through the shell and system calls, then returns the results.
2. ii)
   Differentiate between graphic shells and command line shells?

   Ans: A graphic shell (GUI) uses icons, windows, menus and a mouse, so it is easy for beginners (e.g. Windows Explorer). A command line shell (CLI) takes typed commands, is faster for experts and uses fewer resources (e.g. CMD, Bash).
3. iii)
   What is process life cycle? Named its stages.

   Ans: The process life cycle is the set of states a process goes through from creation to termination. Stages: New, Ready, Running, Waiting (Blocked) and Terminated.
4. iv)
   Why is the operating system referred to as the "central controller"?

   Ans: Because it controls and coordinates all hardware and software resources, deciding which program uses the CPU, memory and devices, and when.
5. v)
   Define one way to create a new user account in Windows

   Ans: Open Settings → Accounts → Family & other users → Add someone else to this PC, then enter the user name and password. (Control Panel → User Accounts also works.)
6. vi)
   What is the role of a file system?

   Ans: A file system names, organizes, stores and retrieves data in files and folders on a storage device, manages free space and controls access permissions.

1. i)
   Why virtual memory is compulsory for today's technology?

   Ans: It lets programs larger than RAM run and lets many applications work together by using disk space as extra memory, which prevents slowdowns and crashes when RAM is full.
2. ii)
   Named computer-based file system used by different operating systems.

   Ans: FAT32 and NTFS (Windows), ext4 (Linux), APFS (macOS).
3. iii)
   What is network operating system? Also write its applications.

   Ans: A network operating system runs on a server and manages users, files, printers and security for the computers connected to a network. Applications: file and print sharing, user authentication, web and email servers (e.g. Windows Server, Linux).
4. iv)
   Define multitasking in computer system.

   Ans: Multitasking is running more than one task or program at the same time; the CPU switches between them so quickly that they appear to run together.
5. v)
   Why is virtual memory slower than RAM?

   Ans: Virtual memory uses the hard disk or SSD, which is much slower than RAM chips, and data must be swapped between disk and RAM.
6. vi)
   How is kernel different from shell.

   Ans: The kernel is the core of the OS that works directly with hardware (memory, processes, devices). The shell is the interface that takes user commands and passes them to the kernel.

1. i)
   Which system call is used to retrieve data from input devices? Give an example.

   Ans: The read system call. Example: read() in Linux reads data typed on the keyboard or stored in a file.
2. ii)
   What did you know FCFS? Give an example.

   Ans: FCFS (First Come First Served) is a scheduling method in which processes are served in the order they arrive. Example: if P1, P2, P3 arrive in that order, the CPU runs P1, then P2, then P3.
3. iii)
   Why device drivers are important in Ms window.

   Ans: A device driver lets Windows communicate with hardware such as a printer or graphics card. Without the correct driver, the device will not work properly.
4. iv)
   Give one example of a system library and its purpose.

   Ans: The C library (libc) in Linux. It provides ready-made functions such as printf() and wraps system calls so programs can use OS services easily.
5. v)
   Define a system call.

   Ans: A system call is the way a program requests a service from the OS kernel, e.g. open, read, write, fork.
6. vi)
   Explain one advantage and one disadvantage of FCFS scheduling.

   Ans: Advantage: it is simple and fair, as processes are served in arrival order. Disadvantage: a long process can make short ones wait (convoy effect), so average waiting time can be high.

(PART- II)