Longitudinal Extend and Time Difference

Duration: 3 min

This video lesson is available to enrolled students.

Return to /learn/SSC-JE-NON-TECHNICAL-COURSE/general-awareness/geography/indian-geography-core-static/asset-longitudinal-extend-and-time-difference after enrolling

Inside: a video lesson and guided study material.

Module outline

  1. General Intelligence & Reasoning: Non Verbal Reasoning (Spatial Aptitude) (Spatial Reasoning) (Visual Reasoning), Series (Number and Letter Series) (Numerical Relations and Reasoning), Coding Decoding, Analogy, Blood Relations, Data Sufficiency, Number System, HCF LCM, Selection Decision Table (Decision Making), Logical Sequence Of Words, Directions (Direction Test), Ranking, Order and Sequence, Syllogisms, Venn Diagram, Deductive and Inductive Reasoning (Logical Deduction and Induction) (Prepositional Reasoning), Puzzle Solving (Puzzles), Data Arrangement, Analytical Reasoning (Counting Figures Reasoning), Cubes & Dices, Calendar, Clock, Arithmetic, Verbal Analogy (Word Based Analogy), Numerical Reasoning, Patterns in Two-Dimensional Figures, Assembling and Grouping of Shapes, Transformation of Shapes, Three-Dimensional Patterns and Visualization, Coding and Decoding, Cubes and Dice, Series Completion, Alphabet and Word Tests, Analogy and Classification, Vocabulary, Mathematical Operations, Direction Sense, Number System, Averages, Mixtures and Alligation, Percentages, Logical Deduction and Induction, Simplification and Approximation, Algebra, Sequences and Series, Powers, Surds and Logarithms, Constraint Puzzles, Critical Reasoning, Order, Ranking and Sequence, Syllogisms and Venn Diagrams, Reading Comprehension, Speed, Time and Distance, Traverse Surveying, Clocks and Calendars, Permutations and Combinations, Narrative Sequencing, Project Monitoring, Resources and Safety, Profit, Loss and Discount, Ratio and Proportion, Time and Work, Mensuration, Data Interpretation, 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, Seating Arrangements, Permutation and Combination, Combinatorics
  2. General Awareness: Physics, Chemistry, Biology, History, Geography, Polity, Indian Economy, Environment, Static General Knowledge, GK- Current Affairs
  3. Full-Length Mock Tests:
  4. Sectional Tests:
AI summary & chapters

AI Summary

An AI-generated summary of this video lecture.

The video is a lecture on the longitudinal extent and time difference in India, presented on a digital whiteboard. The instructor begins by stating that India spans 30 degrees of longitude, from 68°7'E to 97°25'E. The core concept explained is that each degree of longitude corresponds to a 4-minute difference in time. Using this, the total time difference across India is calculated as 30 degrees multiplied by 4 minutes, which equals 120 minutes, or 2 hours. The lecture concludes by applying this to a real-world example: the sun rises approximately two hours earlier in Arunachal Pradesh (the easternmost state) compared to Gujarat (the westernmost state). The instructor uses on-screen text, handwritten calculations, and a diagram of the Earth to illustrate the concept.

Chapters

  1. 0:00 – 2:00 00:00-02:00

    The video opens with a slide titled '6. Longitudinal Extent and Time Difference'. The instructor states that India extends over 30 degrees of longitude, from 68°7'E to 97°25'E. The key principle is introduced: each degree of longitude corresponds to 4 minutes of time difference. The calculation is shown as '30 degrees x 4 minutes = 120 minutes = 2 hours'. The slide text explains that this means the sun rises about two hours earlier in the easternmost part of India (e.g., Arunachal Pradesh) than in the westernmost part (e.g., Gujarat). The instructor begins to write a calculation on the board, starting with '360° = 24 hours'.

  2. 2:00 – 3:17 02:00-03:17

    The instructor continues the calculation on the whiteboard. He writes '360° = 24 hours' and then divides 24 hours by 360 degrees to find the time per degree, writing '24/360 = 1/15 hours'. He then converts this to minutes, writing '1/15 hours = 60/15 = 4 minutes'. This confirms the 4-minute rule. He then draws a diagram of the Earth, showing the 30-degree longitudinal span from 68°7'E to 97°25'E, and circles the 30-degree difference. He reiterates the final calculation: '30 degrees x 4 minutes = 120 minutes = 2 hours'. The on-screen text remains visible, reinforcing the concept that this time difference causes the sun to rise two hours earlier in the east.

The lecture systematically explains the relationship between longitude and time. It starts with the factual extent of India's longitudinal span, establishes the fundamental rule that 1 degree of longitude equals 4 minutes of time, and then applies this rule to calculate the total time difference across the country. The process is reinforced with a step-by-step calculation on the board and a visual diagram of the Earth, culminating in a practical example of how this time difference affects the sunrise time between the eastern and western extremities of India.

Loading lesson…