This chapter explains latitude, longitude, and their role in determining time zones. Understanding these concepts is essential for navigation and mapping the Earth.
Latitude, Longitude and Time - Quick Look Revision Guide
Your 1-page summary of the most exam-relevant takeaways from Practical Work in Geography.
This compact guide covers 20 must-know concepts from Latitude, Longitude and Time aligned with Class 11 preparation for Geography. Ideal for last-minute revision or daily review.
Complete study summary
Essential formulas, key terms, and important concepts for quick reference and revision.
Key Points
Define Latitude.
Latitude measures the angular distance north or south of the equator in degrees.
What are Parallels of Latitude?
Imaginary lines that run parallel to the equator, marking specified latitudinal degrees.
Define Longitude.
Longitude measures angular distance east or west of the Prime Meridian in degrees.
Meridians of Longitude explained.
Vertical lines converging at the poles, marking longitudinal degrees west or east.
What is the Equator?
The equator is the 0° latitude line, dividing Earth into the northern and southern hemispheres.
Great Circles vs. Small Circles.
Great circles divide the Earth into equal halves; small circles do not, varying in size.
Geographical Coordinates.
Latitude and longitude combined provide precise locations on a map or globe.
Earth's rotation time.
The Earth rotates 360° in 24 hours, leading to a rotation speed of 15° per hour.
Measure of one degree of latitude.
One degree of latitude is approximately 111 km anywhere on Earth.
Local Time determination.
Local time varies; it is calculated based on the longitudinal distance from the Prime Meridian.
Standard Meridian.
The standard meridian is used to define a country's time zone; for India, it's 82°30'E.
Understanding Time Zones.
The world has 24 major time zones corresponding to longitudes, adjusted for local time.
International Date Line.
Located at approximately 180° longitude, it marks the point where the date changes.
Difference in time calculation.
For every degree east/west of the Prime Meridian, local time adjusts by 4 minutes.
Role of the Prime Meridian.
The Prime Meridian (0°) serves as the reference for longitudinal measurements worldwide.
Understanding East and West Hemispheres.
The Earth is divided into eastern and western hemispheres, defined by the Prime Meridian.
Time relation to Longitude.
Each 15° of longitude equates to 1 hour of time difference from Greenwich Mean Time.
Drawing Latitude Lines.
Draw horizontal lines parallel to the equator, marking each degree of latitude with accuracy.
Drawing Longitude Lines.
Vertical lines that meet at the poles; spaced widest at the equator and tapering towards it.
Time at Thimphu example.
At 90° E, when Greenwich is 12:00, Thimphu's local time is 6:00 PM due to time difference.
Time at New Orleans example.
At 90° W, if Greenwich is 12:00, local New Orleans time is 6:00 AM due to time difference.
This chapter introduces the concept of maps, their significance, and how they represent the Earth visually.
Start chapterThis chapter explains the importance of map scales, methods of measuring distances, and understanding spatial relationships on maps.
Start chapterThis chapter explores map projections, their purpose, and the different types used in geography.
Start chapterThis chapter explains topographical maps, highlighting their role in depicting natural and cultural features. Understanding these maps is essential for geographers to analyze landscapes and human activities.
Start chapterThis chapter introduces remote sensing, a method for gathering information about objects from a distance, and its significance in geography and environmental studies.
Start chapter
