Exercise Solutions Available
Step-by-step answers for all textbook questions in this chapter
Globe — Exercise Solutions
Use this guide alongside the Samacheer Kalvi textbook. Solve every question on your own first, then check below.
I. Choose the Best Answer (MCQs)
Q1. The shape of the Earth is \_\_\_\_\_\_. (a) Sphere (b) Geoid (c) Cylinder (d) Cone
The Earth is not a perfect sphere. It is slightly flattened at the poles and bulged at the Equator. This unique shape is called a geoid, meaning "earth-shaped."
Q2. The North Pole is \_\_\_\_\_\_. (a) 90° S Latitude (b) 90° N Latitude (c) 0° Latitude (d) 180° Longitude
The North Pole lies at 90° North latitude, which is the northernmost point on Earth.
Q3. The area between 0° and 180° E lines of longitude is called \_\_\_\_\_\_. (a) Western Hemisphere (b) Northern Hemisphere (c) Eastern Hemisphere (d) Southern Hemisphere
The region from 0° (Prime Meridian) to 180° East longitude forms the Eastern Hemisphere.
Q4. The 23½° N line of latitude is called \_\_\_\_\_\_. (a) Tropic of Capricorn (b) Tropic of Cancer (c) Arctic Circle (d) Equator
The Tropic of Cancer is at 23½° N. It marks the northernmost latitude where the Sun appears directly overhead at least once a year.
Q5. 180° line of longitude is \_\_\_\_\_\_. (a) Prime Meridian (b) Tropic of Cancer (c) International Date Line (d) Equator
The 180° longitude is generally the International Date Line, where the calendar date changes.
Q6. The Sun is found overhead the Greenwich Meridian at \_\_\_\_\_\_. (a) 6 a.m. (b) 6 p.m. (c) 12 midnight (d) 12 noon
When the Sun is directly overhead a line of longitude, it is 12 noon local time at all places on that longitude.
Q7. A day has \_\_\_\_\_\_ minutes. (a) 1440 (b) 1140 (c) 2440 (d) 360
A day has 24 hours × 60 minutes = 1440 minutes. Since Earth rotates 360° in 24 hours, it rotates 1° every 4 minutes.
Q8. Longitude considered for Indian Standard Time is \_\_\_\_\_\_. (a) 80° E (b) 82½° E (c) 90° E (d) 77° E
India has adopted 82½° E as its standard meridian for calculating Indian Standard Time (IST), which is 5 hours 30 minutes ahead of GMT.
Q9. Total number of lines of latitude is \_\_\_\_\_\_. (a) 180 (b) 360 (c) 181 (d) 90
Latitudes range from 0° (Equator) to 90° N and 90° S, giving 90 + 90 + 1 (Equator) = 181 lines of latitude.
Q10. Total number of lines of longitude is \_\_\_\_\_\_. (a) 181 (b) 360 (c) 180 (d) 90
Longitudes range from 0° to 180° E and 180° W, totaling 360 lines of longitude (180 E + 180 W).
II. Fill in the Blanks
1. The line of latitude which is known as the Great Circle is the Equator.
2. The imaginary lines drawn horizontally on Earth from the West to East are called Parallels of latitude.
3. The 90° lines of latitude on the Earth are called North Pole and South Pole.
4. The Prime Meridian is also called Greenwich Meridian.
5. The world is divided into 24 time zones.
III. Circle the Odd One
Q1. North Pole, South Pole, Equator, International Date Line
North Pole, South Pole, and Equator are related to latitude. The International Date Line is a line of longitude.
Q2. Tropic of Capricorn, Tropic of Cancer, Equator, Prime Meridian
Tropic of Capricorn, Tropic of Cancer, and Equator are lines of latitude. The Prime Meridian is a line of longitude.
Q3. Torrid Zone, Time Zone, Temperate Zone, Frigid Zone
Torrid Zone, Temperate Zone, and Frigid Zone are heat zones. Time Zone is related to longitude and time calculation.
Q4. Royal Astronomical Observatory, Prime Meridian, Greenwich Meridian, International Date Line
Prime Meridian, Greenwich Meridian, and International Date Line are lines or concepts of longitude. The Royal Astronomical Observatory is a building/institution, not a line of longitude.
Q5. 10° North, 20° South, 30° North, 40° West
10° North, 20° South, and 30° North specify latitude (N/S direction with no East/West). 40° West is a longitude reference that combines with East/West notation.
IV. Match the Following
| A | B | Answer |
|---|---|---|
| 0° line of latitude | Equator | Equator ✓ |
| 0° line of longitude | Greenwich | Greenwich ✓ |
| 180° line of longitude | International Date Line | International Date Line ✓ |
| 90° line of latitude | Pole | Pole ✓ |
V. Examine the Statements
Statements: 1. Earth is spherical in shape. 2. Shape of Earth is called geoid. 3. Earth is flat.
Options: (a) 1 and 3 are correct (b) 2 and 3 are correct (c) 1 and 2 are correct (d) All are correct
The Earth is spherical in shape and its unique shape is called a geoid. The Earth is not flat — statement 3 is incorrect.
Statement I: Lines of latitude are used to find location and define heat zones. Statement II: Lines of longitude are used to find location and calculate time.
Lines of latitude help determine location north-south and define heat zones (Torrid, Temperate, Frigid). Lines of longitude help determine location east-west and calculate time differences.
VI. Name the Following
1. Imaginary lines drawn horizontally on Earth → Latitudes (Parallels of latitude)
2. Imaginary lines drawn vertically on Earth → Longitudes (Meridians of longitude)
3. Three-dimensional model of the Earth → Globe
4. India is located in this hemisphere based on lines of longitude → Eastern Hemisphere
5. Network of lines of latitude and longitude → Earth Grid (Graticule)
VII. Very Short Answer Questions
Q1. What is a geoid?
The Earth has a unique shape — it is slightly flattened at the poles and bulged at the Equator. This shape cannot be compared with any other geometrical shape, so it is called a geoid (earth-shaped).
Q2. What is local time?
When the Sun is overhead on a particular line of longitude, it is 12 noon at all places located on that line of longitude. This is called local time. Local time varies from one longitude to another.
Q3. How many times would the Sun pass overhead a line of longitude?
The Sun passes overhead on a line of longitude only once a day. This is when it is 12 noon at that longitude.
Q4. What are lines of latitude and longitude?
- Lines of latitude: Imaginary lines that run east-west (horizontally) on the Earth, parallel to the Equator. They are also called parallels of latitude.
- Lines of longitude: Imaginary lines drawn vertically connecting the North Pole and South Pole. They are also called meridians of longitude.
Q5. Name the four hemispheres of the Earth.
1. Northern Hemisphere — area between the Equator (0°) and the North Pole (90° N) 2. Southern Hemisphere — area between the Equator (0°) and the South Pole (90° S) 3. Eastern Hemisphere — area between 0° and 180° East longitude 4. Western Hemisphere — area between 0° and 180° West longitude
VIII. Short Answer Questions
Q1. Why is the 0° line of longitude called the Greenwich Meridian?
All nations of the world agreed to have the 0° line of longitude pass through Greenwich, England, where the Royal Astronomical Observatory is located. This line passes through Greenwich and is therefore called the Greenwich Meridian. It serves as the international reference for calculating time zones.
Q2. Why are regions between 66½° latitude and the poles (90°) called the Frigid Zone?
The regions between 66½° latitude and the poles receive very slanting rays of the Sun. Because the sunlight hits at such a low angle, the heat is spread over a large area and the temperature remains very low throughout the year. Hence, this zone is called the Frigid Zone (frigid means extremely cold).
Q3. Why does the International Date Line run zigzag?
If the International Date Line were drawn as a straight line along the 180° longitude, it would cut through some countries and island groups, causing two places in the same country to have different dates. To avoid such confusion, the International Date Line runs in a zigzag manner, deviating around land masses and country boundaries.
IX. Detailed Answer Questions
Q1. What are the uses of a globe?
A globe is a three-dimensional model of the Earth. Its main uses are:
1. Accurate representation — It is the only accurate way to study the whole Earth because it shows the correct shape, size, and location of continents and oceans. 2. Shows distribution — It clearly shows the distribution of land and water on Earth. 3. Locating features — It helps locate sea routes, air routes, rivers, mountains, cities, and countries. 4. Understanding latitudes and longitudes — It helps visualise the network of latitudes and longitudes (Earth Grid). 5. Understanding hemispheres — It shows how the Earth is divided into Northern, Southern, Eastern, and Western Hemispheres. 6. Heat zones — It helps understand the Torrid, Temperate, and Frigid Zones.
Q2. How are hemispheres divided on the basis of lines of latitude and longitude? Explain.
The Earth is divided into four hemispheres:
On the basis of latitudes (Equator — 0°):
| Hemisphere | Extent | Description |
|---|---|---|
| Northern Hemisphere | 0° to 90° N | Area between the Equator and the North Pole |
| Southern Hemisphere | 0° to 90° S | Area between the Equator and the South Pole |
On the basis of longitudes (Prime Meridian — 0°):
| Hemisphere | Extent | Description |
|---|---|---|
| Eastern Hemisphere | 0° to 180° E | Area between Prime Meridian and 180° East longitude |
| Western Hemisphere | 0° to 180° W | Area between Prime Meridian and 180° West longitude |
Q3. Explain the significant lines of latitude and the heat zones between them.
Significant lines of latitude:
| Line of Latitude | Degree | Significance |
|---|---|---|
| Equator | 0° | Divides Earth into Northern and Southern Hemispheres |
| Tropic of Cancer | 23½° N | Northern boundary of Torrid Zone |
| Tropic of Capricorn | 23½° S | Southern boundary of Torrid Zone |
| Arctic Circle | 66½° N | Northern boundary of Temperate Zone |
| Antarctic Circle | 66½° S | Southern boundary of Temperate Zone |
| North Pole | 90° N | Northernmost point |
| South Pole | 90° S | Southernmost point |
Heat Zones:
| Zone | Extent | Characteristics |
|---|---|---|
| Torrid Zone | Between Tropic of Cancer (23½° N) and Tropic of Capricorn (23½° S) | Receives direct sunlight; hottest zone |
| Temperate Zone | Between Tropics and Arctic/Antarctic Circles | Receives moderate sunlight; moderate temperature |
| Frigid Zone | Between Arctic/Antarctic Circles and Poles | Receives slanting sunlight; extremely cold |
Q4. Explain Indian Standard Time in detail.
India's longitudinal extent stretches from 68°7′ E to 97°25′ E, which means 29 lines of longitude pass through India. If each longitude had its own local time, India would have 29 different local times — which is not practical.
Therefore, India has adopted 82½° E longitude as its standard meridian. The local time at this meridian is observed as Indian Standard Time (IST) across the entire country.
Key facts:
- IST is 5 hours 30 minutes ahead of GMT (Greenwich Mean Time).
- When it is 12 noon at Greenwich, it is 5:30 PM in India.
- The 82½° E meridian passes through Mirzapur (near Allahabad) in Uttar Pradesh.
- IST ensures uniformity of time across India for administrative, transport, and communication purposes.
Additional Practice Questions
MCQs
Q1. The Equator divides the Earth into \_\_\_\_\_\_. (a) Eastern and Western Hemispheres (b) Northern and Southern Hemispheres (c) Torrid and Temperate Zones (d) Arctic and Antarctic Zones
The Equator (0° latitude) divides the Earth into the Northern and Southern Hemispheres.
Q2. The distance between two consecutive lines of latitude is approximately \_\_\_\_\_\_. (a) 111 km (b) 100 km (c) 150 km (d) 90 km
Each degree of latitude is approximately 111 km (69 miles) apart.
Q3. The number of longitudes that pass through India is \_\_\_\_\_\_. (a) 27 (b) 28 (c) 29 (d) 30
India's longitudinal extent from 68°7′ E to 97°25′ E means 29 lines of longitude pass through it.
Q4. Which of the following is also known as the Great Circle? (a) Tropic of Cancer (b) Tropic of Capricorn (c) Equator (d) Prime Meridian
The Equator is the largest circle that can be drawn on the globe and divides it into two equal halves, hence called the Great Circle.
Q5. Time difference for every 1° of longitude is \_\_\_\_\_\_. (a) 2 minutes (b) 4 minutes (c) 6 minutes (d) 1 minute
Earth rotates 360° in 24 hours (1440 minutes). Time per degree = 1440 ÷ 360 = 4 minutes.
Fill in the Blanks (Additional)
1. The line that divides the Earth into Northern and Southern Hemispheres is the Equator. 2. The latitudinal value of the Tropic of Capricorn is 23½° S. 3. The longitudinal extent of India is from 68°7′ E to 97°25′ E. 4. The Earth rotates from west to east. 5. When it is 12 noon at Greenwich, the time in India is 5:30 PM. 6. The Arctic Circle is located at 66½° N latitude. 7. The Earth completes one rotation in approximately 24 hours.
Match the Following (Additional)
| A | B | Answer |
|---|---|---|
| Tropic of Cancer | 23½° N | 23½° N ✓ |
| Tropic of Capricorn | 23½° S | 23½° S ✓ |
| Arctic Circle | 66½° N | 66½° N ✓ |
| Antarctic Circle | 66½° S | 66½° S ✓ |
| North Pole | 90° N | 90° N ✓ |
| South Pole | 90° S | 90° S ✓ |
Common Mistakes
1. Confusing the total number of latitudes and longitudes — There are 181 lines of latitude (0° to 90° N and 0° to 90° S, with the Equator counted once) but 360 lines of longitude (0° to 180° E and 0° to 180° W). Remember: latitudes count the Equator once.
2. Mixing up latitude and longitude — Latitudes run east-west (horizontal) and measure north-south position. Longitudes run north-south (vertical) and measure east-west position. Think: "Latitude = flat lines, Longitude = long lines."
3. Saying the Earth is a perfect sphere — The Earth is a geoid (slightly flattened at the poles, bulging at the Equator). Do not call it a perfect sphere.
4. Confusing Tropic of Cancer and Tropic of Capricorn — Tropic of Cancer is at 23½° N (north of the Equator). Tropic of Capricorn is at 23½° S (south of the Equator).
5. Thinking the International Date Line is a straight line — It zigzags to avoid splitting countries into two different dates.
6. Confusing IST and GMT — IST is 5 hours 30 minutes ahead of GMT, not behind. When it is 12 noon at Greenwich, it is 5:30 PM in India.
7. Confusing heat zones with hemispheres — Heat zones (Torrid, Temperate, Frigid) are based on latitude and sunlight. Hemispheres are divisions of the Earth (Northern, Southern, Eastern, Western).
Exam Checklist
- [ ] Can define a globe and list its uses
- [ ] Can explain the shape of the Earth as a geoid
- [ ] Can define and differentiate latitudes and longitudes
- [ ] Can name all significant lines of latitude (Equator, Tropics, Arctic/Antarctic Circles, Poles)
- [ ] Can identify and explain the three heat zones (Torrid, Temperate, Frigid)
- [ ] Can explain how the Earth is divided into four hemispheres
- [ ] Can explain the Prime Meridian and Greenwich Mean Time
- [ ] Can explain the International Date Line and why it zigzags
- [ ] Can calculate time differences using longitude (4 minutes per degree)
- [ ] Can explain Indian Standard Time (82½° E, 5:30 hours ahead of GMT)
- [ ] Can identify odd-one-out questions based on latitude vs longitude
- [ ] Can match lines of latitude/longitude with their correct names