Case 4_ Two Trains Crossing One Other (Same Direction)

Duration: 13 min

This video lesson is available to enrolled students.

Return to /learn/DSSSB-TGT-COMPUTER-SCIENCE-COMPLETE-COURSE/arithmetical-numerical-ability/speed-time-and-distance/train-problems/asset-case-4-two-trains-crossing-one-other-same-direction after enrolling

Inside: a video lesson and guided study material.

Module outline

  1. About Course: About the Course
  2. Section A: General Awareness: Polity, Physics, Biology, Chemistry, Static General Knowledge, History, Geography, Indian Economy, GK- Current Affairs, Evolution of Indian Banking (Banking & Financial Awareness), Environment
  3. Section A: General Intelligence & Reasoning ability: Series (Number and Letter Series) (Numerical Relations and Reasoning), Coding Decoding, Data Sufficiency, Non Verbal Reasoning (Spatial Aptitude) (Spatial Reasoning) (Visual Reasoning), Analytical Reasoning (Counting Figures Reasoning), Blood Relations, Syllogisms, Deductive and Inductive Reasoning (Logical Deduction and Induction) (Prepositional Reasoning), Seating Arrangements, Directions (Direction Test), Puzzle Solving (Puzzles), Calendar, Clock, Cubes & Dices, Selection Decision Table (Decision Making), Logical Sequence Of Words, Crypt Arithmetic, Venn Diagram, Data Arrangement, Inequality, Analogy, Ranking, Order and Sequence, TCS NQT Advanced Reasoning Ability
  4. Section A: Arithmetical & Numerical Ability: Ratio and Proportion (Ratios), Divisibility Rules, Data Interpretation, Mixture and Alligation, Permutation and Combination, Logarithm, Number System, HCF LCM, Sequence and Series (Series), Speed Time and Distance, Percentage, Average, Profit and Loss, Simple Interest and Compound Interest, Time and Work, Pipe and Cistern, Mensuration and Geometry, Powers and Exponents (Surds and Indices), Algebra, Probability, Mental Ability, Age Problems, Partnership, Statistics, Arithmetic, Speed Mathematics and Basic Mathematics, Miscellaneous
  5. Section A: English Language & Comprehension: Vocabulary, Subject Verb Agreement (Verb Noun Agreement), Adjectives, Tenses, Comprehension / Reading Comprehension / Unseen Passages (Critical Reasoning) (Paragraph Questions), Articles, Sentence Construction, Preposition, Direct and Indirect Speech, Sentence Completion (Fill in the blanks), Sentence Re-arrangements (Para Jumbles) (Narrative Sequencing), Modals, Active Passive Voice (Voice), Sentence Correction (Error Correction), Adverb, Conjunction, Cloze Test (Cloze Passage)
  6. Section A: Hindi Language & Comprehension: भाषा, लिपि, ध्वनि, वर्ण, अक्षर, स्वर, व्यंजन, मात्रा और संयुक्ताक्षर, वर्तनी, वर्ण-विन्यास, अनुस्वार, अनुनासिक, चंद्रबिंदु और ‘र’ के रूप, शब्द, पद और शब्द-भेद, संज्ञा और सर्वनाम, विशेषण और क्रिया, लिंग, वचन, पुरुष और कारक, काल, वाच्य, वाक्य और वाक्य-भेद, संधि, समास, विलोम शब्द, पर्यायवाची शब्द, सामान्य अशुद्धियाँ, अनेक शब्दों के लिए एक शब्द, मुहावरे और लोकोक्तियाँ, अपठित गद्यांश और अपठित पद्यांश, Multi-Topic Content (Cross-Concept Material), वर्णमाला
  7. Section B: Programming, Data Structures, OOP & Java: 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, Java, OOPS with C++, Language Design, Intro to Compilers, Visual Basics, Syntax Analysis: Bottom-Up, Object Oriented Technology
  8. Section B: Computer Networks, TCP/IP & Network Security: Introduction to CN, Data Communication, DLL: Flow Control, DLL: Access Control, DLL: Error Control, Data Link Layer - Ethernet, Net Layer: IPv4 & Proto, Net Layer: IP Addressing, Transport Layer Services, TL: Congestion & UDP, Application Layer, Hardware basics, Network Access Technologies, Network Security, Society, Law & Ethics, Mobile Computing, Net Layer:Routing Protocol, Cyber Safety and Security
  9. Section B: Teaching Methodology: Child Development, Concept of Pedagogy, Theories, Inclusive Education, Experiential Pedagogy, Assessment & Evaluation, Curriculum Framework & Reforms, National Education Policy (NEP) 2020, Psychology, Teaching-Learning Process, Personality Development, Teaching Methods & Strategies, Learning and Motivation, Learners & Learning Process, Factors Affecting Teaching, Methods of Teaching, Nature, Objectives & Characteristics of Teaching, Teaching-Learning Aids & ICT Integration, Classroom Management & Communication, Evaluation, Assessment & Measurement, Curriculum & School Environment, Inclusive Education & Special Needs, Professional Development & Ethics
  10. Section B: Digital Electronics / Boolean Logic: Digital Systems & Boolean Basics, Logic Gates & Hardware, Boolean Expression, Boolean Minimization, Combinational Circuit, Sequential Circuits, Number System, Number Representation, Analog-Digital Conversion
  11. Section B: Operating Systems & Linux: Introduction to OS, Process Management, CPU Scheduling, Process Synchronization, Threads & Process Creation, Deadlock, Memory Management, Virtual Memory, File Management, Disc Scheduling, Unix OS, Linux OS, Distributed Systems, Windows OS
  12. Section B: Data Base Management System: Basics of DBMS, ER Diagram, Relational Model & Functional Dependencies, Keys & Integrity Constraints, Normalization (1NF - BCNF), Decomposition Properties & 4NF, Relational Algebra, SQL, File Organization & Indexing, Transaction Management, Concurrency Control, Database Security & Authorization, Database Recovery, Data Warehousing & Mining
  13. Section B: Internet & Web Technologies: Website, Browser & Services, Internet Fundamentals, Web Design & Development, Protocols & Services, Web Publishing & Hosting, Server Side & Security, HTML Basics, CSS, Emerging Technologies, JavaScript-Basics, .Net Programming, Electronic Data Interchange and E-Commerce, XML
  14. Section B: Computer Fundamentals, IT Basics & Architecture: Basics of COA, Cache Memory Organization, Input Output Organisation, Register Transfer and Microoperations, Control Unit Design, Programming the Basic Computer, Terms & Abbreviations, MS Office Applications, Instr Formats & Modes, Floating Point Rep
  15. Section B: Python Language: Introduction to Python, Tokens, Variables, Data Types, I/O, Operators & Expressions, Control Flow & Looping, Collections & Strings, Functions & Modules, File Handling & Data Analysis
  16. Section B: Software Engineering: Fundamentals of Software Engineering, Software Requirements and Quality Assurance, Software Design, Estimation and Metrics, Software Testing, Software Maintenance and Configuration Management, extras, Fundamentals of Systems and Information Systems
  17. Section B: Design & Analysis of Algorithms: Algorithm Analysis, Time Complexity Analysis, Sorting Algorithms, Greedy Algorithms, Dynamic Programming, Minimum Spanning Trees, Shortest Path Algos, Advanced Algorithms
  18. Section B: Mathematics: Linear Algebra, Calculus, Trigonometry, Vectors, Set Theory, Functions, Relations, Propositional and Predicate Logic, Research Process Steps, Graph Theory
  19. Section B: Computer Graphics, Multimedia & Mobile Computing: Basics of Computer Graphics, 2-D Geometrical Transforms and Viewing, 3-D Object Representation, Geometric Transformations and Viewing, Multimedia
  20. Section B: Emerging Trends: Emerging Tech Trends, Knowledge Representation, Natural Language Processing
  21. DSSSB Previous Year Paper:
  22. Business Studies and Management: Business Communication, Business Organization and Management, Financial Accounting, Business Economics, Management Information System (MIS), Knowledge Management & New Economy
AI summary & chapters

AI Summary

An AI-generated summary of this video lecture.

This educational video provides a comprehensive tutorial on solving "Train Problems," specifically focusing on "Case 4: Two Trains Moving In Same Direction." Presented by Yash Jain from Knowledge Gate Eduventures, the lecture begins by establishing the fundamental concepts of relative speed and total distance required for trains to cross each other. The instructor systematically works through three distinct numerical examples, demonstrating the step-by-step application of formulas, unit conversions between kilometers per hour and meters per second, and algebraic manipulation to find unknown variables such as time, length, and speed. The visual aids include on-screen text of the problems, handwritten calculations on a digital whiteboard, and diagrams illustrating train movements. The lesson is structured to take students from basic understanding to advanced problem-solving techniques, ensuring clarity in each step of the mathematical process.

Chapters

  1. 0:00 – 2:00 00:00-02:00

    The video opens with an introductory title card reading "PROBLEM ON TRAINS" and "Basic To Advance" by Yash Jain. It transitions to a slide titled "Case 4: Two Trains Moving In Same Direction," decorated with rocket and planet icons. The instructor explains the concept of relative speed when two objects move in the same direction, drawing arrows to indicate direction and writing "diff" to signify that the relative speed is the difference between the two speeds. He introduces the basic formula S = d/t (Speed = Distance / Time) as the foundation for solving these problems. He emphasizes that for trains moving in the same direction, the relative speed is calculated by subtracting the slower speed from the faster speed, a key distinction from opposite direction problems.

  2. 2:00 – 5:00 02:00-05:00

    The first numerical problem is introduced: "Two trains Bangalore Rajdhani (length 80 meters) and Gondwana Express (length 100 meters) are moving on parallel tracks in the same direction with speeds 90 kmph and 60 kmph. Find the time (in seconds) in which Bangalore Rajdhani will cross Gondwana Express completely." The instructor underlines the key values and calculates the relative speed as 90 - 60 = 30 kmph. He converts this to meters per second using the factor 5/18, resulting in 25/3 m/s. He then calculates the total distance as the sum of lengths (80 + 100 = 180 meters). Finally, he applies the formula t = d/s to find the time, resulting in 21.6 seconds. He writes out the calculation t = 180 / (25/3) = 180 x 3 / 25 = 108/5 = 21.6 sec on the board, showing the intermediate steps clearly.

  3. 5:00 – 10:00 05:00-10:00

    The second problem involves "Patalkot Express and Shreedham Express" moving in the same direction with speeds of 72 km/hr and 54 km/hr. They cross each other in 20 seconds, and the length of the faster train is 40 meters. The goal is to find the length of the slower train. The instructor converts the speeds to m/s (20 m/s and 15 m/s) and determines the relative speed is 5 m/s. He sets up the equation 5 = (40 + x) / 20, where x is the unknown length. Solving this, he finds the length of the slower train to be 60 meters. He writes the conversion steps clearly on the board, showing 72 x 5/18 = 20 and 54 x 5/18 = 15. An image of a train station sign reading "Shree Dham Jabalpur" is visible, adding context to the problem.

  4. 10:00 – 13:03 10:00-13:03

    The final problem features "Kaleen Express and Guddu Express" with lengths of 65 meters and 105 meters respectively. They cross each other in 51/2 seconds, and the speed of Kaleen Express is 84 kmph. The task is to find the speed of Guddu Express. The instructor calculates the total distance (170 meters) and the relative speed in m/s (20/3 m/s). He converts this relative speed to kmph (24 kmph). Using the relationship |84 - S2| = 24, he solves for the speed of Guddu Express, determining it to be 60 kmph. He writes the conversion from m/s to kmph as multiplying by 18/5. The instructor circles the final answer of 60 kmph to highlight the solution.

The video effectively guides students through the logic of relative motion for trains moving in the same direction. By breaking down the process into identifying given values, calculating relative speed (difference of speeds), summing the lengths for total distance, and applying the time-speed-distance formula, the instructor provides a clear methodology. The progression from finding time to finding length and finally finding speed demonstrates the versatility of the core concepts. The consistent use of unit conversion (5/18 factor) is emphasized as a critical step for accuracy in these problems. The instructor's handwritten notes on the digital whiteboard serve as a visual guide for students to follow along with the calculations, ensuring they understand the derivation of each result.

Loading lesson…