| Book Name | : School Geography |
| Subject | : Geography |
| Class | : 9 (Madhyamik) |
| Publisher | : Bengal Book Syndicate (P) Ltd. |
| Chapter Name | : Determination of Location of a Place on Earth’s Surface |
Identify the correct answers
Question 1 (a)
The imaginary lines drawn from east to west are called orbits/latitudes/ longitudes/hemispheres.
Answer
The imaginary lines drawn from east to west are called orbits latitudes.
Question 1 (b)
Equator/axis/orbit/latitude is an imaginary circle on Earth’s surface lying equidistant from the two poles.
Answer
Equator is an imaginary circle on Earth’s surface lying equidistant from the two poles.
Question 1 (c)
There are 25°/75°/90°/49° parallels of latitude on either side of the equator.
Answer
There are 25° parallels of latitude on either side of the equator.
Question 1 (d)
The value of the Tropic of Capricorn is 23½° N / 23½° S / 66½° N / 66½° S.
Answer
The value of the Tropic of Capricorn is 23½° S.
Question 1 (e)
The subsolar point on the Tropic of cancer is on 22nd December/23rd September / 21st June / 21st March.
Answer
The subsolar point on the Tropic of Cancer is on the 21st of June.
Question 1 (f)
The latitudes from 30° to 60° are called low latitudes / high latitudes / mid-latitudes / polar latitudes.
Answer
The latitudes from 30° to 60° are called mid-latitudes.
Question 1 (g)
The heat zone of the earth where temperature remains high throughout the year is called temperate zone / frigid zone / Torrid zone / Wet zone.
Answer
The heat zone of the earth where the temperature remains high throughout the year is called the Torrid zone.
Question 1 (h)
The linear distance between two meridians shortens / lengthens / widens / straightens from equator toward the poles.
Answer
The linear distance between two meridians widens from the equator towards the poles.
Question 1 (i)
The Prime meridian passes through the Royal Astronomical observatory at Netherlands/Greenwic h/
Answer
The Prime Meridian passes through Greenwich, England.
Question 1 (j)
There are 14/ 24 / 19 / 26 time zones in the world based on the Prime Meridian.
Answer
There are 24 time zones in the world based on the Prime Meridian.
Question 1 (k)
A place located on 160°E meridian should have its antipode at 40°E/180°W/0°/ 20°W.
Answer
A place located on 160°E meridian should have its antipode at 20°W.
Question 1 (l)
The International Dateline lies along the meridian 0°/180°80°/60°.
Answer
The International Dateline lies along the meridian 180°.
Question 1 (m)
The time difference between IST and GMT is 5 hrs 54 mins/5 hrs 30 mins/ 6 hrs 30 mins/4 hours 30 mins.
Answer
The time difference between IST (Indian Standard Time) and GMT (Greenwich Mean Time) is 5 hours 30 minutes.
Question 1 (n)
The time difference for 1° longitude is 4 minutes / 4 seconds / 4 hours / 40 minutes.
Answer
The time difference for 1° longitude is 4 minutes.
Question 1 (o)
The great circle / small circle / half circle / full circle route between two points represents the shortest line between the two points.
Answer
The great circle route between two points represents the shortest line between the two points.
If the sentence is true write T and if false write F against the following
- All parallels are semicircles.
- The northern part of the Prime Meridian is called the Northern Hemisphere.
- A traveler crossing the International Date Line westwards loses a day.
- The point of intersection of axis and latitude gives the exact location of a place.
- The highest possible latitude is 180°.
- The Indian standard Meridian passes through Allahabad at 80°30’E meridian.
Answer
- False; Parallels are circles that run parallel to the equator.
- False; The Prime Meridian is an imaginary line that runs from the North Pole to the South Pole and it does not divide the Earth into hemispheres.
- True
- True
- False; The highest possible latitude is 90°.
- False; The Indian Standard Meridian passes through 82.5° E longitude.
Fill in the blanks with the correct words
- The value of the equator is ____.
- The ____ are two places on the Earth’s surface situated just opposite to each other.
- Longitude is the angular distance measured in degrees along the equator on the east and west of ____.
- The regions that lie between 60° to 90° (poles) are referred to as ____.
- The Greenwich time is denoted by an extremely accurate timekeeper (watch) named ____.
- zero (0)
- antipodes
- the Prime Meridian
- Polar Regions
- Harrison’s Chronometer
Write who am I in the following (in word or words)
Question 4 (a)
I am a semi-circular imaginary line. I join the north pole and south pole of the earth. Who am I?
Answer
You are the Longitude.
Question 4 (b)
I am the local time of 82°30′ E. I am ahead o Greenwich Mean Time (G.M.T.) by 5 hours 30 mins. Who am I?
Answer
You are Indian Standard Time (IST).
Question 4 (c)
I am the greatest possible circle drawn on earth My value is 0°. Who am I?
Answer
You are the Equator.
Question 4 (d)
I am an imaginary line. I follow 180° longitude when you cross me eastwards you gain a day. Who am I?
Answer
You are the International Date Line (IDL).
Correct the following sentences
Question 5 (a)
The time of a day from midnight to midday (12 noon) is indicated by P.M.
Answer
The time of a day from midday (12 noon) to midnight is indicated by P.M. (Post Meridiem).
Question 5 (b)
The longitudes are east-west lines that encircle the earth.
Answer
The longitudes are north-south lines that encircle the earth.
Question 5 (c)
The latitudes are semi-circular lines.
Latitudes are horizontal lines that circle the Earth.
Answer
Question 5 (d)
The equator passes through Greenwich, a suburb near London.
Answer
The Prime Meridian passes through Greenwich, a suburb near London.
Short answer type questions
Question 6 (a)
What are Meridians of Longitude?
Answer
Meridians of longitude are a set of imaginary lines on the Earth’s surface that run from the North Pole to the South Pole and measure a location’s distance east or west of the Prime Meridian. There are 360 meridians of longitude, each separated by 1 degree of arc, and the Prime Meridian is assigned a value of 0 degrees.
Question 6 (b)
What are Parallels of Latitude?
Answer
Parallels of latitude are imaginary circles that run parallel to the Equator and circle the Earth from east to west. These circles are measured in degrees north or south of the Equator and are used to locate a place on the Earth’s surface. The Equator itself is a special parallel of latitude with a value of 0 degrees.
Question 6 (c)
What is Local time?
Answer
Local time is the time of a particular place based on the position of the Sun in the sky. It is usually measured in relation to the time at the Prime Meridian, which is known as Greenwich Mean Time (GMT). The local time at a place changes as you move east or west of the Prime Meridian, with each 15-degree increment of longitude corresponding to a one-hour time difference.
Question 6 (d)
What is G.M.T.?
Answer
GMT stands for Greenwich Mean Time, which is the time at the Prime Meridian, the imaginary line that runs from the North Pole to the South Pole through Greenwich, England. It is a time reference point used to standardize time zones around the world. GMT is often used as the base time for calculating time differences between different locations.
Question 6 (f)
What is Time Zone?
Answer
A time zone is a geographical area on Earth where all the clocks have the same standard time. Time zones are established to avoid confusion when communicating the time across different regions, especially in a world where people and events are increasingly global. There are 24 primary time zones that are roughly 15 degrees of longitude wide and are based on the position of the Sun relative to the Prime Meridian.
Question 6 (g)
What are Antipodes?
Answer
Antipodes are two points on the Earth’s surface that are diametrically opposite to each other. They are the furthest points away from each other that you can get on Earth without going through the Earth’s center. When you are standing at one of the antipodes, the other point is directly beneath you, and the distance between the two points is half the Earth’s circumference.
Question 6 (h)
What is Prime Meridian?
Answer
The Prime Meridian is an imaginary line that runs from the North Pole to the South Pole through Greenwich, England, and it is designated as 0 degrees longitude. It is used as a reference line for measuring longitude east or west of it. The Prime Meridian is an important geographical reference point that has helped to standardize time zones around the world.
Question 6 (i)
What is the importance of IDL?
Answer
The International Date Line (IDL) is an imaginary line that roughly follows the 180 degrees longitude line and serves as the divide between two consecutive calendar days. The IDL is important because it helps to maintain a consistent global timekeeping system by ensuring that the same calendar day is being observed across the world at any given time.
Answer the following questions
Question 7 (a)
Why does a traveller experience change of climate while travelling from the equator toward the pole?
Answer
A traveller experiences a change in climate while travelling from the equator toward the pole because of the way the Earth is tilted on its axis. At the equator, the Sun’s rays hit the Earth’s surface directly, making the region hotter. As one moves toward the poles, the angle at which the Sun’s rays hit the Earth becomes shallower, resulting in less direct sunlight and cooler temperatures. Additionally, the circulation of the Earth’s atmosphere and ocean currents also play a role in determining the climate of a region.
Question 7 (b)
What is a time zone? Why is our earth divided into 24 time zones ?
Answer
A time zone is a geographical region where all the clocks have the same standard time. Our earth is divided into 24 time zones, with each zone roughly spanning 15 degrees of longitude, because the Earth rotates 360 degrees around its axis in 24 hours. By dividing the Earth into 24 time zones, each time zone is one hour ahead or behind its adjacent zone, creating a standardized way to measure time across the globe. Time zones help to avoid confusion when communicating the time across different regions, especially in a world where people and events are increasingly global.
Question 7 (c)
Write any three properties each of parallels of latitude and meridians of longitude.
Answer
Properties of parallels of latitude:
- They run parallel to the equator.
- They are measured in degrees north or south of the equator.
- They are used to locate a place on the Earth’s surface.
Properties of meridians of longitude:
- They run from the North Pole to the South Pole.
- They are measured in degrees east or west of the Prime Meridian.
- They are used to determine a location’s distance from the Prime Meridian.
Question 7 (d)
What is International Date Line ?
Answer
The International Date Line (IDL) is an imaginary line on the Earth’s surface that roughly follows the 180 degrees longitude line and serves as the divide between two consecutive calendar days. When you cross the IDL, you either gain or lose a calendar day, depending on the direction of your travel. The IDL is important because it helps to maintain a consistent global timekeeping system by ensuring that the same calendar day is being observed across the world at any given time.
Question 7 (e)
Why are latitudes parallel but not of the same size?
Answer
Latitudes are parallel to the equator but are not of the same size because the Earth is not a perfect sphere, it bulges at the equator and flattens at the poles. As a result, the distance around the Earth is greater at the equator than at the poles. This means that circles of latitude become smaller as they get closer to the poles. Therefore, latitudes are parallel to each other but their size decreases as they move away from the equator toward the poles.
Question 7 (f)
What is the difference between the Tropic of Cancer and the Tropic of Capricorn ?
Answer
| Tropic of Cancer | Tropic of Capricorn |
|---|---|
| Located at 23.5° north of the Equator | Located at 23.5° south of the Equator |
| Northernmost point where the Sun’s rays are directly overhead on the summer solstice in the northern hemisphere | Southernmost point where the Sun’s rays are directly overhead on the summer solstice in the southern hemisphere |
| Marks the start of summer in the northern hemisphere | Marks the start of summer in the southern hemisphere |
Match the column
Question 8
| Column A | Column B |
| (1) Latitude | (a) 0° |
| (2) Longitude | (b) 82°30’E |
| (3) Equator | (c) Time |
| (4) Prime Meridian | (d) Heat zones |
| (5) Indian Standard (central) Meridian | (e) divides the Earth into two halves |
Answer
| Column A | Column B |
|---|---|
| (1) Latitude | (d) Heat zones |
| (2) Longitude | (c) Time |
| (3) Equator | (e) divides the Earth into two halves |
| (4) Prime Meridian | (a) 0° |
| (5) Indian Standard (central) Meridian | (b) 82°30’E |
Question 9
Cross-Word
Clues
Across
(5) Parallel Lines drawn from east to west encircling the Earth.
Down-
(1) Abbreviated form of International Date Line.
(2) The largest possible circle on Earth.
(3) The imaginary line that is equidistant from the two poles.
(4) Short form of Greenwich Mean Time.
Answer
Across: (5) Latitude
Down: (1) IDL (2) Equator (3) Tropic (4) GMT
Long answer or essay-type questions
Question 10 (a)
What are latitudes ? Describe the properties of latitude.
Answer
Latitudes are imaginary circles on the Earth’s surface that are drawn parallel to the equator, which is the circle that lies equidistant from the North and South poles.
The properties of latitude are :
- Latitudes are imaginary circles parallel to the equator on Earth’s surface
- They are measured in degrees north or south of the equator
- They are spaced at regular intervals
- They help in locating places on Earth’s surface
- They indicate different climate zones
Question 10 (b)
How does latitude help in determining the climate of any region? Explain.
Answer
Latitude helps in determining the climate of any region by dividing the Earth into three zones based on its distance from the equator, which are the Torrid Zone, Temperate Zone, and Frigid Zone.
The Torrid Zone, which is located between the Tropic of Cancer and the Tropic of Capricorn, receives the most direct sunlight throughout the year and therefore has a consistently warm climate.
The Temperate Zone, which is located between the Tropic of Cancer and the Arctic Circle in the Northern Hemisphere and the Tropic of Capricorn and the Antarctic Circle in the Southern Hemisphere, receives varying amounts of direct sunlight throughout the year and therefore has a climate that varies with the seasons.
The Frigid Zone, which is located near the poles, receives very little direct sunlight throughout the year and therefore has a consistently cold climate.
Question 10 (c)
Describe the heat zones of the earth.
Answer
The heat zones of the Earth are determined by the latitude and the angle at which the sun’s rays hit the Earth’s surface. There are three main heat zones of the Earth: the Torrid Zone, Temperate Zone, and Frigid Zone.
- The Torrid Zone: This zone is located between the Tropic of Cancer and the Tropic of Capricorn, which is roughly between 23.5 degrees north and south of the equator. The Torrid Zone receives the most direct sunlight throughout the year, which results in a hot and humid climate.
- The Temperate Zone: This zone is located between the Tropic of Cancer and the Arctic Circle in the Northern Hemisphere and the Tropic of Capricorn and the Antarctic Circle in the Southern Hemisphere. The Temperate Zone receives varying amounts of direct sunlight throughout the year, which results in a range of climates from mild to moderate.
- The Frigid Zone: This zone is located near the poles, which is above the Arctic Circle in the Northern Hemisphere and below the Antarctic Circle in the Southern Hemisphere. The Frigid Zone receives very little direct sunlight throughout the year, which results in a cold and harsh climate.
Question 10 (d)
What are longitudes ? Describe the properties of longitude.
Answer
Longitudes are imaginary lines that run from the North Pole to the South Pole on the Earth’s surface. They are also known as meridians and are used to measure a location’s distance east or west of the Prime Meridian, which is designated as 0 degrees longitude.
The properties of longitude
- Longitudes are imaginary lines that run from the North Pole to the South Pole.
- They measure a location’s distance east or west of the Prime Meridian.
- They are measured in degrees, minutes, and seconds.
- Longitudes intersect at the poles and are spaced at regular intervals of 1 degree.
Question 10 (e)
How is longitude related to time? Explain with examples.
Answer
Longitude is closely related to time because the rotation of the Earth around its axis causes the sun to appear to rise and set at different times in different parts of the world. To account for this, the Earth has been divided into 24 time zones, each one covering 15 degrees of longitude, with the Prime Meridian at 0 degrees longitude serving as the reference point for determining the time.
For example, if it is noon at the Prime Meridian, which passes through Greenwich, London, it will be 5:30 PM in India, which lies in the time zone 82.5 degrees east of the Prime Meridian. Similarly, if it is midnight at the Prime Meridian, it will be 7:00 PM in New York, which lies in the time zone 75 degrees west of the Prime Meridian.
Longitude is used to determine the difference in time between two places on Earth, which is crucial for scheduling events, transportation, and communication across different time zones.
Question 10 (f)
What is International Date Line? Describe its importance.
Answer
The International Date Line is an imaginary line on the Earth’s surface that roughly follows the 180th meridian and marks the place where the date changes by one day when crossing from east to west or vice versa.
Its importance is as follows:
- It marks the place where the date changes by one day when crossing from east to west or vice versa.
- It serves as the reference line for calculating time differences between different parts of the world.
- It is important for navigation and communication, as it helps to synchronize time across different time zones and prevent confusion.
- The location of the International Date Line can cause some areas to be a day ahead or behind, depending on which side of the line they are on.
Question 10 (g)
Write the differences of the Parallels of Latitude and Meridians of Longitude.
Answer
| Parallels of Latitude | Meridians of Longitude |
|---|---|
| Drawn parallel to the equator | Run from the North Pole to the South Pole |
| Measure a location’s distance north or south of the equator | Measure a location’s distance east or west of the Prime Meridian |
| Spaced at regular intervals of 1 degree | Converge at the poles |
| The longest parallel of latitude is the Equator (0°) | The longest meridian of longitude is the Prime Meridian (0°) |
| Do not intersect each other | Intersect at the poles |
Problems on Time and Longitude
Question 11 (a)
The longitude of Kolkata and Seoul are 88°30’E and 127°06’E. respectively. What is the local time in Seoul when it is 12 noon at Kolkata?
Answer
The time difference between Kolkata and Seoul can be calculated by finding the difference in their longitudes and dividing by 15 (since 15 degrees of longitude correspond to 1 hour of time difference):
The time difference between Kolkata and Seoul
= (127°06’E – 88°30’E) × 4
= (126°66’E – 88°30’E) × 4
= 38°36’× 4
= 38° × 4 + 36’× 4
= 152 min + 144 sec
= 154 min 24 sec
= 2 hours 34 minutes 24 sec
Since Kolkata is ahead of Greenwich Mean Time (GMT) by 5 hours 30 minutes (IST), we need to add this time difference to find the local time in Seoul:
Local time in Seoul = Kolkata time + time difference
= 12:00 PM + 2 hours 34 minutes
= 2:34 PM
Therefore, when it is 12 noon at Kolkata, the local time in Seoul is 2:34 PM.
Question 11 (b)
A hockey match held at Atlanta (85°W) Olympic at 6 a.m. was telecast directly. When it was visible at Kolkata (88°30’E) ?
Answer
To determine the time at Kolkata when the hockey match in Atlanta was visible, we need to find the time difference between the two locations. Since Atlanta is west of Kolkata, we need to subtract the longitude of Atlanta from the longitude of Kolkata:
Time difference between Atlanta and Kolkata
= 88°30’E – 85°W
= 88°30’E + 85°E
= 173°30’E × 4
= 173.5°E × 4
= 694 min or 11 hours 34 minutes
Therefore, when the hockey match in Atlanta started at 6 a.m., the time in Kolkata was 11 hours 34 minutes ahead, which means it was:
6:00 AM + 11 hours 34 minutes = 5:34 PM
So the hockey match was visible in Kolkata at 5:34 PM.
Question 11 (c)
At town A (5°N, 60°W), the time is 7:30 p.m. At town B, the local time is 4:15 p.m. What is the longitude of town B?
Answer
To calculate the longitude of town B, we need to find the time difference between the two towns. Since town A is west of town B, we need to subtract the local time at town B from the local time at town A:
Time difference = 7:30 PM – 4:15 PM
= 3 hours 15 minutes
= 180 min + 15 min
= 195 min
So, town B is 195 minutes behind town A.
Now, to find the longitude of town B, we can use the conversion rate of 4 minutes per degree of longitude:
195 minutes / 4 minutes/degree = 48.75 degrees
So, town B is located at approximately 48.75 degrees west longitude.
Question 11 (d)
When it is 08.30 p.m. Friday, 31st December 2010 A.D. at New York (74°west) what would be the local time, day, date at Kolkata (88°30’East) ?
Answer
First, we need to convert the longitude values into a common unit. Since New York is at 74°W and Kolkata is at 88°30’E, we can convert Kolkata’s longitude to a negative value:
Time difference = (88°30′ + 74°) × 4
= 162°30′ × 4
= 162.5° × 4
= 650 min or 10 hours 50 minutes
This means that Kolkata is ahead of New York by 10 hours 50 minutes.
Now we can add this time difference to the time and date in New York:
Local time in Kolkata = 8:30 PM + 10 hours 50 minutes
= 7:20 AM (next day)
Therefore, when it is 08:30 PM on Friday, December 31, 2010, in New York, the local time in Kolkata is 7:20 AM on Saturday, January 1, 2011.
Question 11 (e)
What would be the local time and date of New York (74°W) when it is 9 a.m. in Kolkata (88°30’E) on 1st January 2009 ?
Answer
Time difference = (88°30′ + 74°) × 4
= 162°30′ × 4
= 162.5° × 4
= 650 min or 10 hours 50 minutes
New York time = 9 a.m. – 10 hours 50 minutes = 10:10 p.m. (previous day)
So, the local time and date in New York would be 10:10 p.m. on 31st December 2008.
Question 11 (f)
What would be the local time at Kolkata (88°30’E) when it is midday at Greenwich?
Answer
Time difference = 88°30’E × 4
= 88.5° E × 4
= 354 minutes or 5 hours 54 minutes
Therefore, when it is midday at Greenwich, the time at Kolkata will be:
Kolkata time = 12:00 p.m. + 5 hours 54 minute
= 5:54 p.m.
So, the local time at Kolkata when it is midday at Greenwich would be 5:54 p.m.
Question 11 (g)
What would be the local time and date of Kolkata (88°30’E) when it is 7 p.m. in London (0°) on 28th February 1990?
Answer
Time difference = (88°30’E – 0°) × 4
= 88.5° E × 4
= 354 minutes or 5 hours 54 minutes
Therefore, when it is 7 p.m. in London, the time in Kolkata will be:
Kolkata time = 7 p.m. + 5 hours 54 minutes
= 12:54 a.m. (next day)
So, the local time and date in Kolkata would be 12:54 a.m. on 1st March 1990.
Question 11 (h)
When it is 2 p.m. at town X (20°N 30°E) and 5:15 p.m. at town Y, what would be the longitude of the town Y?
Answer
Time difference = 5:15 p.m. – 2:00 p.m.
= 3 hours 15 minutes
We know that one hour of time difference corresponds to 15 degrees of longitude. So, the longitude difference between town Y and town X can be calculated as:
Longitude difference = Time difference × 15 = 3.25 × 15
= 48.75 degrees
Therefore, the longitude of town Y would be 30°E + 48.75 degrees
= 78.75°E (approx.)
Question 11 (i)
Calculate the longitude of the position of a ship whose captain observes that It is 6.30 p.m. in the Chronometer when the local time in mid-ocean is 1.00 p.m.
Answer
Time difference = 6:30 pm – 1:00 pm
= 5 hours 30 minutes
Longitude difference = 5.5 × 15 = 82.5 degrees (since one hour corresponds to 15 degrees of longitude)
Therefore, the longitude of the ship’s position = 82.5 degrees
Question 11 (j)
The time at station A is 10 a.m. and station B is 7 p.m. when it is 12 noon at Greenwich (O°). What are the longitudes of the two stations?
Answer
For station A:
- Time Difference for A = 12:00 (GMT) – 10:00 (Local Time at A) = 2 hours
- Longitude Difference for A = 2 hours × 15 = 30 degrees
- Longitude of Station A = 0° ± 30° = 30°E
For station B:
- Time Difference for B = 12:00 (GMT) – 19:00 (Local Time at B) = -7 hours
- Longitude Difference for B = -7 hours × 15 = -105 degrees
- Longitude of Station B = 0° ± (-105°) = 105°E
So, the longitude of station A is 30°E, and the longitude of station B is 105°E.
Question 11 (k)
When It is 5 a.m. at Shillong (72°E), Los Angeles has local time 2:58 p.m. of the previous day. What is the Longitude of Los Angeles?
Answer
Time Difference = Shillong time – Los Angeles time
Time Difference = 5:00 a.m. – 2:58 p.m. (previous day)
= 14 hours and 2 minutes
Longitude Difference = 14 hours and 2 minutes × 15
=
