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

Duration: 13 min

This video lesson is available to enrolled students.

Return to /learn/BIHAR-STET-COMPUTER-SCIENCE-COMPLETE-COURSE/mathematical-aptitude/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 the course: About the Course
  2. Mathematical Aptitude: संख्या पद्धति / Number System, महत्तम समापवर्तक और लघुत्तम समापवर्त्य / HCF and LCM, Divisibility Rules, प्रतिशत / Percentage, अनुपात और समानुपात / Ratio and Proportion, औसत / Average, लाभ, हानि और बट्टा / Profit, Loss and Discount, समय और कार्य / Time and Work, घन क्षेत्रमिति / Solid Mensuration, साधारण और चक्रवृद्धि ब्याज / Simple and Compound Interest, समय, चाल और दूरी / Time, Speed and Distance, Age Problems, मिश्रण और एलिगेशन / Mixture and Alligation, Algebra, सरलीकरण, घातांक और करणी / Simplification, Indices and Surds, Pipe and Cistern, Trigonometry, Statistics, आँकड़ा निर्वचन / Data Interpretation, Arithmetic, समुच्चय, संबंध, फलन और विविक्त गणित / Sets, Relations, Functions and Discrete Mathematics, संख्या पद्धति और संख्या सिद्धांत / Number Systems and Number Theory, निर्देशांक ज्यामिति, सदिश और त्रिविमीय ज्यामिति / Coordinate Geometry, Vectors and 3D Geometry, बहुपद, समीकरण और सम्मिश्र संख्याएँ / Polynomials, Equations and Complex Numbers
  3. Logical Reasoning: श्रेणी / Series, कूट लेखन एवं कूट वाचन / Coding-Decoding, सादृश्यता एवं वर्गीकरण / Analogy and Classification, रक्त संबंध / Blood Relations, दिशा एवं दूरी / Direction and Distance, क्रम एवं रैंकिंग / Order and Ranking, अशाब्दिक तर्क / Non-Verbal Reasoning, बैठक व्यवस्था एवं पहेलियाँ / Seating Arrangement and Puzzles, Syllogisms, वेन आरेख, न्याय वाक्य एवं असमानता / Venn Diagrams, Syllogism and Inequalities, गणितीय संक्रियाएँ एवं लुप्त संख्या / Mathematical Operations and Missing Numbers, वर्णमाला एवं संख्या परीक्षण / Alphabet and Number Test, कथन आधारित तार्किक विवेचन / Statement-Based Reasoning, Analytical Reasoning (Counting Figures Reasoning), घन, पासा एवं आकृतियों की गिनती / Cubes, Dice and Figure Counting, कैलेंडर एवं घड़ी / Calendar and Clock, Clock
  4. General Knowledge: वैज्ञानिक उपलब्धियाँ और अनुसंधान / Scientific Achievements and Research, Chemistry, Biology, History, Geography, Polity, Indian Economy, समसामयिकी / Current Affairs, Static General Knowledge
  5. Art of Teaching: शिक्षण-अधिगम प्रक्रिया एवं कक्षा प्रबंधन / Teaching-Learning Process and Classroom Management, Learners & Learning Process, Factors Affecting Teaching, शिक्षण विधियाँ एवं उपागम / Teaching Methods and Approaches, सूक्ष्म शिक्षण एवं कक्षा संप्रेषण / Microteaching and Classroom Communication, शिक्षण सहायक सामग्री एवं शैक्षिक तकनीकी / Teaching Aids and Educational Technology, आकलन एवं मूल्यांकन / Assessment and Evaluation, शिक्षक: गुण, व्यावसायिक नैतिकता एवं विकास / Teacher: Qualities, Professional Ethics and Development, शैक्षिक नीतियाँ, अधिनियम एवं प्रशासन / Educational Policies, Acts and Administration, पाठ्यचर्या, कला एवं सह-शैक्षिक क्षेत्र / Curriculum, Arts and Co-curricular Areas, निर्देशन एवं परामर्श / Guidance and Counselling, दिव्यांग बच्चों की शिक्षा / Education of Children with Disabilities, Micro-Teaching & Teaching Skills, पाठ योजना / 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, Node.js
  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, कंप्यूटर नेटवर्क / Computer Networks
  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 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…