Concept & Short Tricks to calculate AVERAGE SPEED (1)
Duration: 14 min
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Inside: a video lesson and guided study material.
Module outline
- Paper 1 | Reasoning Test: Series (Number and Letter Series) (Numerical Relations and Reasoning), Coding Decoding, Data Sufficiency, Syllogisms, Deductive and Inductive Reasoning (Logical Deduction and Induction) (Prepositional Reasoning), Seating Arrangements, Blood Relations, Puzzle Solving (Puzzles), Venn Diagram, Analogy, Ranking, Order and Sequence, Non Verbal Reasoning (Spatial Aptitude) (Spatial Reasoning) (Visual Reasoning), Selection Decision Table (Decision Making), Logical Sequence Of Words, Cubes & Dices, Analytical Reasoning (Counting Figures Reasoning), Calendar, Alphabet and Word Tests, Numerical Reasoning, Number System, Averages, Mixtures and Alligation, Percentages, Series Completion, Analogy and Classification, Patterns in Two-Dimensional Figures, Coding and Decoding, Mathematical Operations, Direction Sense, Algebra, Logical Deduction and Induction, Syllogisms and Venn Diagrams, Critical Reasoning, Order, Ranking and Sequence, Reading Comprehension, Profit, Loss and Discount, Constraint Puzzles, Speed, Time and Distance, Traverse Surveying, Ratio and Proportion, Time and Work, Mensuration, Permutations and Combinations, Clocks and Calendars, Data Interpretation, Assembling and Grouping of Shapes, Transformation of Shapes, Three-Dimensional Patterns and Visualization, Cubes and Dice, Vocabulary, Blood Relations, Data Sufficiency
- Paper 1 | Numerical Analysis: Number System, HCF LCM, Percentage, Ratio and Proportion (Ratios), Average, Sequence and Series (Series), Powers and Exponents (Surds and Indices), Algebra, Statistics, Data Interpretation, Mental Ability, Arithmetic, Logarithm, Profit and Loss, Simple Interest and Compound Interest, Speed Time and Distance, Mixture and Alligation, Mensuration and Geometry, Permutation and Combination, Probability, Sequences and Series, Powers, Surds and Logarithms, Subject-Verb Agreement, Sentence Completion, Geometry, Sentence Structure and Correction, Data Sufficiency, Trigonometry, Measurement and Quantity Take-Off, Signal Space and Optimum Detection, Probability, Statistics, Algebra, Time and Work, Speed, Time and Distance, Data Interpretation, Graph Theory, Combinatorics
- Paper 1 | General Knowledge: State Wise GK, History, Geography, GK- Current Affairs, Static General Knowledge, Polity, Indian Economy
- Paper 1 | DBMS: 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, Relational Calculus, Database Security & Authorization, Database Recovery
- Paper 1 | Data Communication & Network: 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, Network Security, Security in Mobile and Wireless Computing, Input Output Organisation, File Management, Hardware Basics, Terms & Abbreviations, Protocols & Services, Network Access Technologies, Cyber Safety and Security, Basics of COA
- Paper 2 | System Analysis & Design: Fundamentals of Systems and Information Systems, SDLC and Development Approaches, Fundamentals of Software Engineering, Software Requirements and Quality Assurance, Software Documentation and Software Requirements Specification (SRS), SDD and Quality Assurance, Software Design, Estimation and Metrics, Software Testing, Software Maintenance and Configuration Management, Security, Risk Management & Maintenance, extras
- Paper 2 | Programming Language (Java): Java Fundamentals, OOPS with Java, Array, String, IO & References, Generic & Collections, Multithreading, Java, Miscellaneous, Control Flow, OOPS with C++, Stack, C Fundamentals, Arrays & Pointers, Object Oriented Technology, Control Flow & Looping, Introduction to Python
AI summary & chapters
AI Summary
An AI-generated summary of this video lecture.
This educational video is a lecture on the topic of average speed, presented by an instructor named Yash Jain. The video begins with a title slide and then transitions to a whiteboard-style presentation where the instructor explains the fundamental formula for speed: Speed = Distance / Time. He then introduces the concept of average speed, defining it as Total Distance divided by Total Time. The core of the lecture focuses on a specific case: when the distance covered is the same for different segments of a journey. The instructor uses a diagram of a person traveling from 'Home' to 'Office' to illustrate this. He derives the formula for average speed in this scenario, showing that it is the harmonic mean of the individual speeds. The derivation is shown step-by-step, starting with the total distance (2x) and total time (x/s1 + x/s2), which simplifies to 2s1s2/(s1+s2). The lecture then extends this concept to three segments, deriving the formula 3s1s2s3/(s1s2 + s2s3 + s3s1). The video concludes with a final 'Thanks for Watching' screen.
Chapters
0:00 – 2:00 00:00-02:00
The video opens with a title slide featuring the text 'SPEED, TIME & DISTANCE' over a background image of a car driving on a desert road. This transitions to a presentation slide with the same title, now with the text '- By Yash Jain' below it. A small video window in the bottom right corner shows the instructor, Yash Jain, a man with glasses and a blue shirt, speaking. The slide also includes a logo for 'YASH JAIN SIR' and 'KNOWLEDGE GATE EDUCATOR'. The instructor begins his lecture, introducing the topic of average speed.
2:00 – 5:00 02:00-05:00
The slide changes to a new one titled 'AVERAGE SPEED'. The instructor writes the fundamental formula for speed: 'Speed = Distance / Time', and its symbolic form 's = d/t'. He then writes the formula for average speed: 'Average Speed = Total Distance / Total Time'. He explains that average speed is not the arithmetic mean of speeds but the total distance divided by the total time taken. He begins to discuss the first case, which is when the distance covered is the same for different parts of the journey, writing 'Case 1: When Distance Covered is same' on the slide.
5:00 – 10:00 05:00-10:00
The instructor draws a diagram illustrating a journey from 'Home' to 'Office'. He labels the distance as 'x' and the speeds for the two legs of the journey as 's1' and 's2'. He then writes the formula for average speed: 'Avg Speed = Total dist / Total time'. He substitutes the values, writing '2x / (x/s1 + x/s2)'. He simplifies this expression by factoring out 'x' from the denominator, resulting in '2x / (x(1/s1 + 1/s2))'. He cancels 'x' from the numerator and denominator, leaving '2 / (1/s1 + 1/s2)'. He then simplifies this to the final formula: '2s1s2 / (s1 + s2)'. He explains that this is the harmonic mean of the two speeds.
10:00 – 13:41 10:00-13:41
The instructor extends the concept to three segments. He draws a new diagram with three equal distances, each labeled 'x', and speeds 's1', 's2', and 's3'. He writes the formula for average speed as '3x / (x/s1 + x/s2 + x/s3)'. He factors out 'x' from the denominator, simplifying to '3x / (x(1/s1 + 1/s2 + 1/s3))'. After canceling 'x', he gets '3 / (1/s1 + 1/s2 + 1/s3)'. He then multiplies the numerator and denominator by 's1s2s3' to get the final formula: '3s1s2s3 / (s1s2 + s2s3 + s3s1)'. The video ends with a 'THANKS FOR WATCHING' screen.
The video provides a clear, step-by-step derivation of the formula for average speed when the distance covered in each segment of a journey is equal. It starts with the basic definition of speed and builds up to the specific case of average speed for equal distances. The instructor uses a combination of text, diagrams, and algebraic manipulation to explain that the average speed is the harmonic mean of the individual speeds, not their arithmetic mean. This is demonstrated for two and then three segments, providing a generalizable method for solving such problems.

