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GeographyClass 11Practical Work in Geography

Practical Work in Geography | Class 11 Geography Notes

By ConceptScroll Team · Published on 17 July 2026 · 4 min read

Practical Work in Geography – this guide gives you a concise, exam-ready overview of Practical Work in Geography from Class 11 Geography, written by ConceptScroll editors and reviewed against the latest NCERT textbook.

Longitude and Time

The Earth rotates from west to east, causing the sun to appear to rise in the east and set in the west. One complete rotation takes 24 hours, corresponding to 360° of longitude. Since the Earth is divided into 360° of longitude, the sun moves 15° of longitude every hour (360° ÷ 24 hours = 15° per hour). Equivalently, the sun moves 1° of longitude every 4 minutes (60 minutes ÷ 15°).

Time decreases when moving eastward and increases when moving westward. This means local time at a place east of the Prime Meridian is ahead of Greenwich Mean Time (GMT), while local time west of the Prime Meridian is behind GMT.

The local time of any place can be calculated by multiplying the difference in longitude from the Prime Meridian by 4 minutes per degree. For example, Thimpu in Bhutan is at 90°E longitude. Since it is east of Greenwich, its local time is ahead by 90 × 4 = 360 minutes or 6 hours. Therefore, when it is 12 noon at Greenwich, it is 6 p.m. in Thimpu.

Similarly, New Orleans at 90°W longitude is west of Greenwich, so its local time is behind by 6 hours. When it is 12 noon at Greenwich, it is 6 a.m. in New Orleans.

To maintain uniform time within countries, a standard meridian is selected, usually divisible by 7°30' or 15°, so that the time difference from GMT is in whole or half hours. India uses the 82°30'E meridian passing through Mirzapur as its Standard Meridian, making Indian Standard Time (IST) 5 hours 30 minutes ahead of GMT.

Countries with large east-west spans may have multiple time zones, such as Russia, Canada, and the USA. The world is divided into 24 major time zones, each covering 15° of longitude.

📊 Diagram: Figure 3.6 displays the major time zones of the world, showing 24 divisions each spanning 15° of longitude.

🔗 Connection: This section sets the foundation for understanding the International Date Line and how crossing it affects the calendar date.

Frequently asked questions

1. Answer the following questions in about 30 words: (i) Which are the two natural points of references on the earth? (ii) What is a great circle? (iii) What are coordinates? (iv) Why does the sun appear to be moving from east to west? (v) What is meant by local time?

(i) The two natural points of reference on the earth are the North Pole and the South Pole.

(ii) A great circle is any circle drawn on a globe (or sphere) that divides it into two equal halves. It represents the shortest distance between two points on the surface.

(iii) Coordinates are numerical values (latitude and longitude) used to specify the exact location of a place on the earth's surface.

(iv) The sun appears to be moving from east to west because the earth rotates from west to east on

2. Distinguish between latitudes and longitudes.

Latitude:

  • Imaginary horizontal lines running parallel to the Equator.
  • Measure distance north or south of the Equator (0° to 90° N or S).
  • Also called parallels.
  • Used to determine climate zones.

Longitude:

  • Imaginary vertical lines running from pole to pole.
  • Measure distance east or west of the Prime Meridian (0° to 180° E or W).
  • Also called meridians.
  • Used to determine time zones.
## ACTIVITY 1. Find out the locations of the following places with the help of your atlas and write their latitudes and longitudes. | Place | Latitude | Longitude | | --- | --- | --- | | (i) Mumbai | | | | (ii) Vladivostok | | | | (iii) Cairo | | | | (iv) New York | | | | (v) Ottawa | | | | (vi) Geneva | | | | (vii) Johannesburg | | | | (viii) Sydney | | |

Students should refer to an atlas or reliable geographic source to fill in the latitudes and longitudes:

(i) Mumbai: approx. 19° N, 72.8° E (ii) Vladivostok: approx. 43° N, 131.9° E (iii) Cairo: approx. 30° N, 31.2° E (iv) New York: approx. 40.7° N, 74° W (v) Ottawa: approx. 45.4° N, 75.7° W (vi) Geneva: approx. 46.2° N, 6.1° E (vii) Johannesburg: approx. 26.2° S, 28° E (viii) Sydney: approx. 33.9° S, 151.2° E

2. What would be the time of the following cities if the time at Prime Meridian is 10 a.m. (i) Delhi (ii) London (iii) Tokyo (iv) Paris (v) Cairo (vi) Moscow

Given: Time at Prime Meridian (0° longitude) = 10 a.m.

To find local time at other cities, use the formula: Local Time = GMT + (Longitude in degrees × 4 minutes per degree)

Note: East longitude adds time, West longitude subtracts time.

Approximate longitudes:

  • Delhi: 77° E
  • London: 0° (Prime Meridian)
  • Tokyo: 139° E
  • Paris: 2° E
  • Cairo: 31° E
  • Moscow: 37° E

Calculations: (i) Delhi: Time difference = 77° × 4 min = 308 min = 5 hrs 8 min Local time = 10:00 + 5:08 = 3:08 p.m.

(ii) London:

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