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Duration: 11 min

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Inside: a video lesson and guided study material.

Module outline

  1. General Intelligence & Reasoning: Analogy, Non Verbal Reasoning (Spatial Aptitude) (Spatial Reasoning) (Visual Reasoning), Series (Number and Letter Series) (Numerical Relations and Reasoning), Coding Decoding, Blood Relations, Directions (Direction Test), Ranking, Order and Sequence, Logical Sequence Of Words, Syllogisms, Venn Diagram, Deductive and Inductive Reasoning (Logical Deduction and Induction) (Prepositional Reasoning), Selection Decision Table (Decision Making), Data Sufficiency, Puzzle Solving (Puzzles), Data Arrangement, Cubes & Dices, Calendar, Clock, Arithmetic, Number System, HCF LCM, Verbal Analogy (Word Based Analogy), Visual Recognition and Figure Completion, Paper Folding and Cutting, Transformation of Shapes, Clocks and Calendars, Direction Sense, Cubes and Dice, Patterns in Two-Dimensional Figures, Seating Arrangements, Analogy and Classification, Logical Deduction and Induction, Alphabet and Word Tests, Mathematical Operations, Series Completion, Simplification and Approximation, Coding and Decoding, Numerical Reasoning, Assembling and Grouping of Shapes, Three-Dimensional Patterns and Visualization, Vocabulary, Number System, Averages, Mixtures and Alligation, Simple and Compound Interest, Percentages, Algebra, Speed, Time and Distance, Seating and Arrangement Puzzles, Traverse Surveying, Order, Ranking and Sequence, Constraint Puzzles, Syllogisms and Venn Diagrams, Reading Comprehension, Critical Reasoning, Permutations and Combinations, Narrative Sequencing, Project Monitoring, Resources and Safety, Profit, Loss and Discount, Ratio and Proportion, Time and Work, Mensuration, Data Interpretation, Powers, Surds and Logarithms, Sequences and Series, Articles and Determiners, Sentence Completion, Data Sufficiency, Blood Relations, Simple Interest and Compound Interest, Mixture and Alligation, Sequence and Series (Series), Speed Time and Distance, Algebra, Profit and Loss, Powers and Exponents (Surds and Indices), Permutation and Combination
  2. General Awareness: Physics, Chemistry, Biology, History, Geography, Polity, Indian Economy, Environment, Static General Knowledge, GK- Current Affairs, Artificial Intelligence, MS Office Applications, Terms & Abbreviations, Keyboard Shortcuts, Evolution of Indian Banking (Banking & Financial Awareness), Emerging Tech Trends
  3. Engineering Mathematics: Set Theory, Relations, Functions, Graph Theory, Group Theory, Propositional and Predicate Logic, Linear Algebra, Calculus, Probability, Statistics, Signal Space and Optimum Detection, Probability, Statistics
  4. Digital Logic: Digital Systems & Boolean Basics, Logic Gates & Hardware, Boolean Expression, Boolean Minimization, Combinational Circuit, Sequential Circuits, Number System, Number Representation, Floating Point Rep, Number Systems and Codes, Registers and Counters, Boolean Algebra and Logic Gates, Microprocessors and Microcontrollers, Logic Families and CMOS Logic, Microprocessors, Logic Gates and Boolean Algebra, Minimization of Boolean Functions, Timing, Hazards and Testing, Logic Families, Combinational Logic Design, Arithmetic Circuits, Waveform Generators and Timer Circuits, Semiconductor Memories and Programmable Logic Devices, Combinational Logic Circuits, Latches and Flip-Flops, Finite State Machines, Sequential Circuits and State Machines, Minimization of Boolean Functions, Arithmetic Circuits, Latches and Flip-Flops, Number Systems and Codes, Registers and Counters
  5. Computer Organisation & Architecture: Basics of COA, Cache Memory Organization, Input Output Organisation, Pipelining, Instr Formats & Modes, Control Unit Design, Programming the Basic Computer, Register Transfer and Microoperations, Semiconductor Memories and Programmable Logic, Processor Organization and Instructions, Memory Hierarchy and Input/Output, Registers and Counters
  6. Programming & Data Structures: C Fundamentals, Control Flow, Functions, Arrays & Pointers, Storage Classes, Structures & Enums, DMA, Macros, Scoping & File Handling, Introduction to DS, Array, Stack, Queue, Linked List, Tree, Graphs, Hashing, HTML Basics, OOPS with C++, Java, Object Oriented Technology
  7. Databases: Basics of DBMS, ER Diagram, Relational Model & Functional Dependencies, Keys & Integrity Constraints, Normalization (1NF - BCNF), Decomposition Properties & 4NF, File Organization & Indexing, Relational Algebra, SQL, Relational Calculus, Transaction Management, Concurrency Control, Database Recovery, Database Security & Authorization
  8. Algorithms: Algorithm Analysis, Time Complexity Analysis, Sorting Algorithms, Greedy Algorithms, Dynamic Programming, Minimum Spanning Trees, Shortest Path Algos
  9. 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, Complexity Theory
  10. Compiler Design: Intro to Compilers, Lexical Analysis, Grammar & CFG, Syntax Analysis: Top-Down, Syntax Analysis: Bottom-Up, Semantic Analysis & SDT, Intermediate Code Gen, Code Optimization, Run Time Environment
  11. Operating System: Introduction to OS, Process Management, CPU Scheduling, Process Synchronization, Threads & Process Creation, Deadlock, Memory Management, Virtual Memory, Disc Scheduling, File Management, Security, Windows OS, Distributed Systems, Unix OS, Linux OS
  12. Computer Networks: Introduction to CN, 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, Hardware Basics, Data Communication, Website, Browser & Services, Web Design & Development, Network Security, Cyber Threats and Malware Attacks, Cyber Safety and Security
  13. Full Length Mock Tests:
  14. Sectional Tests:
  15. Paper 2 - Full-length Mock Tests:
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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