Person joining or leaving in between

Duration: 12 min

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Inside: a video lesson and guided study material.

Module outline

  1. Child Development and Pedagogy: विकास की अवधारणा / Concept of Development, विकास के मनोवैज्ञानिक सिद्धांत / Psychological Theories of Development, व्यक्तिगत भिन्नताएँ, व्यक्तित्व एवं जेंडर / Individual Differences, Personality and Gender, बुद्धि एवं सृजनात्मकता / Intelligence and Creativity, अधिगम एवं इसके सिद्धांत / Learning and Its Theories, बालक कैसे सोचते एवं सीखते हैं / How Children Think and Learn, संवेग, अभिप्रेरणा, मानसिक स्वास्थ्य एवं निर्देशन / Emotion, Motivation, Mental Health and Guidance, समावेशी शिक्षा / Inclusive Education, शिक्षण-अधिगम प्रक्रिया / Teaching-Learning Process, शिक्षण विधियाँ एवं रणनीतियाँ / Teaching Methods and Strategies, आकलन एवं मूल्यांकन / Assessment and Evaluation, पाठ्यचर्या और विद्यालयी गतिविधियाँ / Curriculum and School Activities, पाठ योजना और शिक्षण कौशल / Lesson Planning and Teaching Skills, शिक्षण संसाधन और शैक्षिक प्रौद्योगिकी / Teaching Resources and Educational Technology, शैक्षिक विचारक, उद्देश्य एवं राष्ट्रीय नीतियाँ / Educational Thinkers, Aims and National Policies, कक्षा प्रबंधन और सम्प्रेषण / Classroom Management and Communication, शिक्षक पहचान और व्यावसायिक विकास / Teacher Identity and Professional Development, सामाजिक विज्ञान शिक्षणशास्त्र / Social Science Pedagogy, सामाजिक एवं राजनीतिक जीवन / Social and Political Life, विज्ञान शिक्षण शास्त्र / Science Pedagogy, जीवन कौशल, मूल्य, शांति एवं पर्यावरण शिक्षा / Life Skills, Values, Peace and Environmental Education, संविधान, आयोग, अधिनियम एवं योजनाएँ / Constitution, Commissions, Acts and Schemes in Education
  2. Mathematics: संख्या पद्धति एवं स्थानीय मान / Number System & Place Value, मूलभूत संक्रियाएँ, सरलीकरण एवं पैटर्न / Basic Operations, Simplification & Patterns, गुणनखंड, विभाज्यता, म.स.प. एवं ल.स.प. / Factors, Divisibility, HCF & LCM, भिन्न एवं दशमलव / Fractions & Decimals, वर्ग, घन, घातांक एवं करणी / Squares, Cubes, Exponents & Surds, मापन: लंबाई, भार, धारिता, समय एवं मुद्रा / Measurement: Length, Mass, Capacity, Time & Money, बीजगणित / Algebra, अनुपात, समानुपात, औसत एवं आयु / Ratio, Proportion, Average & Ages, प्रतिशत, लाभ-हानि एवं ब्याज / Percentage, Profit–Loss & Interest, समय-कार्य एवं चाल-दूरी / Time & Work and Speed–Distance, रेखाएँ, कोण, आकृतियाँ एवं निर्देशांक / Lines, Angles, Shapes & Coordinates, त्रिभुज, चतुर्भुज, वृत्त एवं त्रिकोणमिति / Triangles, Quadrilaterals, Circles & Trigonometry, क्षेत्रमिति: परिमाप, क्षेत्रफल एवं आयतन / Mensuration: Perimeter, Area & Volume, आँकड़ा प्रबंधन, सांख्यिकी एवं प्रायिकता / Data Handling, Statistics & Probability, गणित शिक्षणशास्त्र / Mathematics Pedagogy, वर्णमाला एवं संख्या परीक्षण / Alphabet & Number Test, अशाब्दिक तर्क / Non-Verbal Reasoning, पासा एवं घन / Dice & Cubes, गणितीय संक्रियाएँ एवं अंकगणितीय तर्क / Mathematical Operations & Arithmetical Reasoning, क्रम, बैठक व्यवस्था एवं पहेली / Ranking, Seating Arrangement & Puzzles, कैलेंडर एवं घड़ी / Calendar & Clock, वेन आरेख एवं तार्किक निगमन / Venn Diagrams & Logical Deduction
  3. Environmental Studies: परिवार, मित्र और समुदाय / Family, Friends and Community, पौधे / Plants, जंतु / Animals, खेती और पशुपालन / Farming and Animal Husbandry, भोजन और पोषण / Food and Nutrition, शरीर और स्वास्थ्य / Body and Health, जल / Water, आवास / Shelter, यात्रा, परिवहन और संचार / Travel, Transport and Communication, मानचित्र, दिशाएँ और भारत / Maps, Directions and India, हम क्या बनाते और करते हैं / Things We Make and Do, पृथ्वी, आकाश और आपदाएँ / Earth, Sky and Disasters, पर्यावरण, पारिस्थितिकी और वन्यजीव / Environment, Ecology and Wildlife, प्राकृतिक संसाधन, प्रदूषण और जलवायु परिवर्तन / Natural Resources, Pollution and Climate Change, पर्यावरण अध्ययन का शिक्षणशास्त्र / Pedagogy of Environmental Studies, भौतिक भूगोल / Physical Geography, संसाधन एवं विकास / Resources and Development, बल, दाब, कार्य एवं ऊर्जा / Force, Pressure, Work and Energy, पर्यावरण एवं पारिस्थितिकी / Environment and Ecology, विज्ञान एवं प्रौद्योगिकी / Science & Technology, ऊष्मा एवं ध्वनि / Heat and Sound, प्रकाश / Light, ब्रह्मांड एवं प्राकृतिक परिघटनाएँ / Universe and Natural Phenomena, रासायनिक अभिक्रियाएँ, अम्ल, क्षार एवं लवण / Chemical Reactions, Acids, Bases and Salts, प्राकृतिक वनस्पति, वन्य जीवन एवं विश्व के प्रदेश / Natural Vegetation, Wildlife and World Regions, पर्यावरण एवं जलवायु समसामयिकी / Environment & Climate Affairs
  4. Language I/II — Hindi: भाषा, लिपि और वर्ण-विचार, संधि, शब्द-स्रोत और शब्द-रचना, समास, शब्द-भेद: विकारी और अविकारी, लिंग, वचन, कारक, काल और वाच्य, वाक्य-विचार और शुद्ध लेखन, शब्द-भंडार, रस, छंद, अलंकार और शब्द-शक्ति, हिंदी साहित्य, अपठित बोध, हिंदी शिक्षणशास्त्र
  5. Language I/II — English: Sounds, Spelling and Word Formation, Parts of Speech, Nouns and Pronouns, Articles, Determiners and Adjectives, Verbs and Modals, Tenses and Subject–Verb Agreement, Adverbs, Prepositions and Conjunctions, Sentence Structure, Voice and Narration, Vocabulary, Sentence Correction and Writing Skills, Poetry and English Literature, Reading Comprehension, Pedagogy of English Language
  6. Language I/II — Sanskrit: वर्णविचारः एवं संज्ञाप्रकरणम्, सन्धिप्रकरणम्, शब्दरूपाणि, धातुरूपाणि, कारकाणि एवं विभक्तयः, उपसर्गाः एवं अव्ययानि, प्रत्ययप्रकरणम्, समासप्रकरणम्, वाच्यप्रकरणम्, संख्याज्ञानम्, शब्दज्ञानम् एवं अनुवादः, अपठितावबोधनम्, संस्कृतसाहित्यम् एवं काव्यशास्त्रम्, संस्कृतशिक्षणशास्त्रम्
  7. Language I/II — Urdu: رسم الخط، املا اور تلفظ, ذخیرۂ الفاظ, قواعد, محاورے اور ضرب الامثال, شعر و سخن, اردو ادب کی تاریخ, تفہیمِ عبارت, اردو کی تدریس
  8. Language I/II — Bengali: ভাষা, ধ্বনি ও বর্ণ, সন্ধি ও বানান, শব্দের উৎস ও গঠন, সমাস, পদ পরিচয়, কারক ও বিভক্তি, ক্রিয়া ও কাল, বাক্যতত্ত্ব, শব্দার্থ ও বাগর্থ, পাঠ অনুধাবন ও সাহিত্য, নির্মিতি ও পত্রলিখন, বাংলা শিক্ষণবিদ্যা
  9. अतिरिक्त अभ्यास / Extra Practice (beyond syllabus): कंप्यूटर हार्डवेयर एवं परिधीय उपकरण / Computer Hardware and Peripherals, अंतरराष्ट्रीय संबंध एवं संगठन / International Relations & Organisations, भारतीय अर्थव्यवस्था: आँकड़े एवं समसामयिकी / Indian Economy: Data & Current Affairs
AI summary & chapters

AI Summary

An AI-generated summary of this video lecture.

This educational video is a lecture on solving time and work problems, a common topic in competitive exams. The instructor, Yash Jain Sir, presents a series of four problems, each with a different scenario involving multiple workers. The core concept taught is that the total work done is the sum of the work done by each individual, which is calculated as (Time Worked / Time to Complete Alone). The video demonstrates a systematic approach: first, defining variables for the time each person takes to complete the work alone, then setting up an equation where the sum of the fractions of work completed by each person equals 1 (the whole work). The first problem involves two people working together for a period before one leaves. The second problem features three people with staggered start and end times. The third problem uses the combined work rates of pairs to find an individual's rate. The fourth problem uses the LCM method to simplify calculations. The instructor uses a digital whiteboard to write out the equations and solve them step-by-step, providing a clear, methodical guide for students.

Chapters

  1. 0:00 – 2:00 00:00-02:00

    The video opens with a title card featuring the text 'TIME & WORK' and an illustration of a person working at a computer. It then transitions to a lecture slide for Question 1. The problem states that Gangadhar and Shaktimaan can complete a work in 18 and 24 days respectively. They work together for 8 days, after which Gangadhar leaves, and Shaktimaan finishes the remaining work. The question asks for the number of days Shaktimaan took to finish the remaining work. The instructor, Yash Jain Sir, is visible in a small window in the bottom right corner. The slide also shows the answer as '16/3 days' and the source as 'COGNIZANT 2018'. The instructor begins to explain the problem, setting up the scenario and introducing the concept of work rates.

  2. 2:00 – 5:00 02:00-05:00

    The instructor explains the general formula for time and work problems. He writes on the digital board: 'Time Worked by A / A's alone time + Time Worked by B / B's alone time = 1'. He then applies this to the first problem, defining 'A' as Gangadhar (18 days) and 'B' as Shaktimaan (24 days). He writes the equation: '8/18 + x/24 = 1', where 'x' is the number of days Shaktimaan worked alone. He proceeds to solve the equation step-by-step, first simplifying 8/18 to 4/9, then finding a common denominator of 72, and finally solving for 'x' to get 16/3 days. The instructor emphasizes that the sum of the work done by each person must equal the total work, which is 1.

  3. 5:00 – 10:00 05:00-10:00

    The video transitions to Question 2. The problem states that Ajay, Vijay, and Sujoy can complete a work in 10, 12, and 15 days respectively. They all start together, Ajay leaves after 2 days, and Vijay leaves 3 days before the work is completed. The question asks for the total time taken to complete the work. The instructor sets up the equation: '2/10 + (x-3)/12 + x/15 = 1', where 'x' is the total time. He explains that Ajay worked for 2 days, Vijay worked for (x-3) days, and Sujoy worked for the full 'x' days. He then solves the equation by finding a common denominator of 60, simplifying to '12 + 5(x-3) + 4x = 60', and solving for 'x' to get 7 days. The instructor then moves to Question 3, which states that A and B together can do a work in 12 days, and B and C together can do it in 16 days. After A works for 5 days, B for 7 days, and C for 13 days, the work is completed. The question asks for the number of days C alone would take to finish the work. The instructor sets up the equation: '5/12 + 7/16 + 13/x = 1'.

  4. 10:00 – 11:47 10:00-11:47

    The instructor continues solving Question 3. He simplifies the equation '5/12 + 7/16 + 13/x = 1' by finding a common denominator of 48, which gives '20/48 + 21/48 + 13/x = 1'. This simplifies to '41/48 + 13/x = 1'. He then isolates the term with 'x': '13/x = 1 - 41/48 = 7/48'. Solving for 'x' gives 'x = (13 * 48) / 7', which is approximately 88.57, but the instructor notes this is not among the options. He then re-examines the problem and realizes the work done by A and B is not independent. He corrects the approach by using the combined rates: (A+B)'s 5-day work + (B+C)'s 2-day work + C's 11-day work = 1. He writes the equation: '5/12 + 2/16 + 11/x = 1'. He solves this, finding a common denominator of 48, which gives '20/48 + 6/48 + 11/x = 1', or '26/48 + 11/x = 1'. This simplifies to '11/x = 22/48', and solving for 'x' gives 24 days. The video then moves to Question 4, which involves Hari and Giri working together, with Hari leaving after some days and Giri finishing the remaining work in 47 days. The instructor sets up the equation using the LCM method: 'x/70 + (x+47)/60 = 1'. The video ends with a 'THANKS FOR WATCHING' screen.

The video provides a comprehensive tutorial on solving time and work problems by breaking them down into a systematic process. The central theme is the application of the formula: (Time Worked / Time to Complete Alone) = Fraction of Work Done. The instructor demonstrates this principle across four distinct problem types: two individuals working together and one leaving, three individuals with staggered work periods, using combined work rates to find an individual's rate, and using the LCM method for efficient calculation. The progression from simple to more complex problems, coupled with clear, step-by-step algebraic solutions, equips students with a robust methodology for tackling a wide range of time and work questions in competitive exams.

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