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Duration: 11 min

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Module outline

  1. About the course: About the Course
  2. Mathematical Aptitude: Number System, HCF LCM, Divisibility Rules, Percentage, Ratio and Proportion (Ratios), Average, Profit and Loss, Time and Work, Mensuration and Geometry, Simple Interest and Compound Interest, Speed Time and Distance, Age Problems, Mixture and Alligation, Algebra, Powers and Exponents (Surds and Indices), Pipe and Cistern, Trigonometry, Statistics, Data Interpretation, Arithmetic
  3. Logical Reasoning: Series (Number and Letter Series) (Numerical Relations and Reasoning), Coding Decoding, Analogy, Blood Relations, Directions (Direction Test), Ranking, Order and Sequence, Non Verbal Reasoning (Spatial Aptitude) (Spatial Reasoning) (Visual Reasoning), Seating Arrangements, Syllogisms, Venn Diagram, Puzzle Solving (Puzzles), Logical Sequence Of Words, Deductive and Inductive Reasoning (Logical Deduction and Induction) (Prepositional Reasoning), Analytical Reasoning (Counting Figures Reasoning), Cubes & Dices, Calendar, Clock
  4. General Knowledge: Physics, Chemistry, Biology, History, Geography, Polity, Indian Economy, GK- Current Affairs, Static General Knowledge
  5. Art of Teaching: Nature, Objectives & Characteristics of Teaching, Learners & Learning Process, Factors Affecting Teaching, Methods of Teaching, Classroom Management & Communication, Teaching-Learning Aids & ICT Integration, Evaluation, Assessment & Measurement, Professional Development & Ethics, Policies, Acts & Contemporary Issues, Curriculum & School Environment, Guidance, Counselling & Mental Health, Inclusive Education & Special Needs, Micro-Teaching & Teaching Skills, Lesson Planning
  6. Environmental Science: Environment
  7. Unit 1 | Digital Electronics: Digital Systems & Boolean Basics, Logic Gates & Hardware, Boolean Expression, Boolean Minimization, Combinational Circuit, Sequential Circuits, Number System, Number Representation
  8. Unit 2 | COA: Basics of COA, Floating Point Rep, Cache Memory Organization, Input Output Organisation, Instr Formats & Modes, Control Unit Design, Register Transfer and Microoperations, Programming the Basic Computer
  9. Unit 3 | C Programming: C Fundamentals, Control Flow, Functions, Arrays & Pointers, Storage Classes, Structures & Enums, DMA, Macros, Scoping & File Handling
  10. Unit 3 | Data Structures: Introduction to DS, Array, Stack, Queue, Linked List, Tree, Graphs, Hashing
  11. Unit 4 | Algorithms: Algorithm Analysis, Time Complexity Analysis, Sorting Algorithms, Dynamic Programming, Minimum Spanning Trees, Shortest Path Algos, Advanced Algorithms
  12. Unit 5 | Operating System: Introduction to OS, Process Management, CPU Scheduling, Process Synchronization, Threads & Process Creation, Deadlock, Memory Management, Virtual Memory, Disc Scheduling, File Management
  13. Unit 6 | Database Management System: Basics of DBMS, ER Diagram, Relational Model & Functional Dependencies, Keys & Integrity Constraints, Normalization (1NF - BCNF), Decomposition Properties & 4NF, File Organization & Indexing, Relational Algebra, SQL, Transaction Management, Concurrency Control
  14. Unit 7 | Computer Networks: Introduction to CN, Data Communication, DLL: Access Control, DLL: Flow Control, DLL: Error Control, DLL: Framing, Data Link Layer - Ethernet, Net Layer: IPv4 & Proto, Net Layer: IP Addressing, Net Layer:Routing Protocol, Transport Layer Services, TL: Congestion & UDP, Application Layer
  15. Unit 8 | Software Engineering: Fundamentals of Software Engineering, Software Requirements and Quality Assurance, Software Design, Estimation and Metrics, Software Testing, Software Maintenance and Configuration Management
  16. Unit 9 | Object Oriented Programming: OOPS with C++
  17. Unit 10 | Web Development: HTML Basics, CSS, JavaScript-Basics, XML
  18. Unit 11 | Theory Of Computation: Introduction to TOC, Deterministic FA (DFA), Non-Deterministic FA, Regular Expressions, Grammar, Regular Language Properties, Moore & Mealy Machines, Pushdown Automata & CFG, Turing Machines
  19. Unit 12 | IoT: Emerging Tech Trends, Cloud Computing
  20. Unit 13 | Artificial Intelligence: Approaches to AI, Search Algorithms, Game Playing, Knowledge Representation, Natural Language Processing, Artificial Neural Networks, Genetic Algorithms
  21. Unit 14 | E-Commerce: Electronic Data Interchange and E-Commerce, Role of Internet and Web Services, Security in Mobile and Wireless Computing, Physical Security and Cryptography Basics, Cyber Safety and Security
  22. Unit 15 | Multimedia: Multimedia
  23. Unit 16 | Python: Introduction to Python, Tokens, Variables, Data Types, I/O, Operators & Expressions, Control Flow & Looping, Collections & Strings, Functions & Modules, File Handling & Data Analysis, DSA using Python
  24. Full Length Mock Tests — General Paper:
  25. Full Length Mock Tests — Computer Science (Paper II):
AI summary & chapters

AI Summary

An AI-generated summary of this video lecture.

This lecture demonstrates how to calculate Average Turnaround Time (TAT) and Average Waiting Time (WT) using the First Come First Serve (FCFS) scheduling algorithm. The instructor works through two practice problems on a whiteboard, using a table with columns for Process Number, Arrival Time (AT), Burst Time (BT), Completion Time (CT), TAT = CT - AT, and WT = TAT - BT. For the first problem, processes P0 (AT 0, BT 3), P1 (AT 2, BT 2), and P2 (AT 6, BT 4) are scheduled in arrival order. A Gantt chart shows P0 running from 0 to 3, P1 from 3 to 5, an idle gap from 5 to 6, and P2 from 6 to 10. Completion times are 3, 5, and 10, giving TAT values of 3, 3, and 4, and WT values of 0, 1, and 0. The instructor writes Avg TAT = 10/3 and Avg Waiting Time = 1/3. A second problem uses processes with AT 0, 0, 1 and BT 4, 6, 3. The Gantt chart shows P0 from 0 to 4, P1 from 4 to 10, and P2 from 10 to 13, with CT values 4, 10, 13, TAT values 4, 10, 12, and WT values 0, 4, 9. The instructor writes Avg TAT = 24/3 and Avg WT = 13/3. Ready and Run state diagrams are used to track which processes are waiting and which is executing.

Chapters

  1. 0:00 – 2:00 00:00-02:00

    The whiteboard displays the question: 'Calculate the Average Turnaround Time (TAT) and Average Waiting Time (WT) using the FCFS (First Come First Serve) Scheduling Algorithm.' A table is set up with columns P. No, Arrival Time (AT), Burst Time (BT), Completion Time (CT), TAT = CT - AT, and WT = TAT - BT. Rows show P0 (AT 0, BT 3), P1 (AT 2, BT 2), P2 (AT 6, BT 4), and an empty Average row. The instructor begins drawing a green Gantt chart below the table and labels Ready and Run states in a diagram.

  2. 2:00 – 5:00 02:00-05:00

    The instructor builds the Gantt chart for the first problem: P0 runs from 0 to 3, P1 from 3 to 5, an idle gap is marked in red from 5 to 6, and P2 runs from 6 to 10. Time markers 3, 5, and 6 are written beneath the chart. He then fills the table with pink values: CT 3, 5, 10 and TAT 3, 3, 4. Red checkmarks and circles mark the AT values 0, 2, 6 and BT values 3, 2, 4, confirming the input data before computing derived columns.

  3. 5:00 – 10:00 05:00-10:00

    The instructor completes the first problem by writing Avg Waiting Time = 1/3 and Avg TAT = 10/3 on the right side of the board, alongside Ready and Run circles containing P0, P1, P2. He then introduces a second problem with a new table headed Prd, AT, BT, CT, TAT, WT showing arrival values 0, 0, 1 and burst values 4, 6, 3. He sketches a green Gantt bar and a two-circle diagram labeled 'Ready P0, P1' and 'Run' with a magenta 'FCFS' label, circling the zero arrival entries for P0 and P1.

  4. 10:00 – 11:01 10:00-11:01

    The second problem is completed on the board. The table shows CT values 4, 10, 13 and a TAT-BT/WT column listing 0, 4, 9. The instructor writes Avg TAT = 24/3 and Avg WT = 13/3. A green Gantt chart at the bottom displays P0, P1, P2 with time markers 4, 10, 13, confirming the execution order P0 (0-4), P1 (4-10), P2 (10-13).

The lecture teaches FCFS scheduling through two worked examples. The method is: (1) list processes by arrival time; (2) draw a Gantt chart showing execution order, including idle gaps when no process is ready; (3) compute CT from the Gantt chart; (4) compute TAT = CT - AT; (5) compute WT = TAT - BT; (6) average TAT and WT across all processes. Key evidence: first problem yields CT 3, 5, 10; TAT 3, 3, 4; WT 0, 1, 0; Avg TAT = 10/3; Avg WT = 1/3. Second problem yields CT 4, 10, 13; TAT 4, 10, 12; WT 0, 4, 9; Avg TAT = 24/3; Avg WT = 13/3. The Ready/Run diagram helps track which processes are waiting versus executing. Idle time in the Gantt chart (e.g., 5 to 6 in the first problem) does not contribute to any process's execution but affects completion times of later processes.

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