WBBSE Solutions For Class 7 Geography Chapter 2 Determination Of The Location Of A Place On The Earths Surface Topic B Meridians Of Longitude

WBBSE Chapter 2 Determination Of The Location Of A Place On The Earth Surface Topic B Meridians Of Longitude Long Question And Answers

Question 1. How do we determine the exact location of a place on the Earth’s surface? Or, Determine the location of a place on the Earth’s surface with the help of latitude and longitude. Or, How do you determine the location of a place on the Earth’s surface with a suitable diagram?
Answer:

Determination of the location of a place on the Earth’s surface with the help of latitude and longitude:

Our Earth is a spherical body and to determine the location of any place on its surface, we have to determine the angular distance of the parallel i.e. latitude and angular distance of the meridian, i.e longitude of that place from the centre of the Earth.

The parallels are imaginary circular lines drawn horizontally around the Earth, oriented in an east-west direction, while the meridians are imaginary semi-circular lines extending from north to south.

Read And Learn Also WBBSE Solutions For Class 7 Geography

So the parallels and meridians intersect each other perpendicularly forming a geographic coordinate system. The location of any place on the Earth’s surface can be determined with the help of this grid or geographic coordinate system.

Example-The location of Kolkata is (22°34’N, 88°30’E) i.e. the intersection point of 22°34′ north parallel and 88°30′ east meridian is the actual location of Kolkata on the Earth’s surface.

Question 2. Differentiate between the parallels of latitude and meridians of longitude. Or, Compare and contrast between the parallels of latitude and meridians of longitude.
Answer:

Difference between the parallels of latitude and meridians of longitude:

The difference between the parallels of latitude and meridians of longitude are-

Question 3. Determine the relationship between the lines of longitude and time.
Answer:

Relation between the lines of longitude and time:

Determination and calculation of time is dependent on the lines of longitude to a great extent. The reasons are discussed below-

1. Determination of noon and local time:

• The Earth’s rotation causes all the lines of longitude to experience the Sun overhead at some point of the day.
• This overhead position of the Sun is considered as noon for that place.
• The time for that particular longitude is calculated based on this noon time or 12 o’clock, midday.

2. Determination of time difference based on longitudinal difference:

• The Earth covers 360° as it completes one full rotation. So, the Earth covers 360° in 24 hours, i.e., (360°/24)= 15° in 1 hour or 60 minutes.
• This means for every 1° difference in longitude, we experience a time difference of (60/15) 4 minutes.
• Therefore, it is established that each longitude experiences a different local time.

3. Time difference with GMT:

Time is always ahead of Greenwich Mean Time towards the east and behind towards the west.

4. Calculation of time and longitude:

• The longitudinal difference of the two places can be easily determined if the time difference between those two places is known.
• Moreover, if the longitudes of any two places are known along with the local time of any one place, the time of the other place can be easily calculated.
• Apart from this, if the local times of any two places are known along with the longitude of any one place, the longitude of the other place can be easily calculated.

 

Question 4. The opening ceremony of a game in New York (74°W) had been telecast at 3:44 p.m. in Karachi (67°E). At what time did the ceremony actually start in New York?
Answer:

The opening ceremony of a game in New York (74°W) had been telecast at 3:44 p.m. in Karachi (67°E).

Step 1: The calculation of longitudinal difference.

The longitudinal difference between New York and Karachi is (74°+67°) = 141°

Step 2: The calculation of the time difference. We know,

• For 1° longitudinal difference, the time difference is 4 minutes
• Therefore, for 141° longitudinal time difference is (141 x 4) = 564 minutes or 9 hours 24 minutes
• So, the total time difference is 9 hours and 24 minutes.

Step 3: The time in New York would be behind the time of Karachi, as New York is located to the west of Karachi.

Step 4: So the time of New York would be 3:44 p.m. or 15 hours 44 minutes 9 hours 24 minutes = 6 hours 20 minutes or 6:20 a.m. Therefore, the opening ceremony of the game in New York started at 6:20 a.m. local time.

Question 5. The live telecast of the inauguration ceremony of the London Olympics started at 11:30 p.m. in India. When did the programme start in London?
Answer:

The live telecast of the inauguration ceremony of the London Olympics started at 11:30 p.m. in India.

The longitude of London = 0° Standard Meridian for Indian Standard Time = 82°30’E

Step 1: The calculation of the difference in longitude. The difference in longitude between the two places is = (82°30′- 0) = 82°30′

Step 2: The calculation of the time difference between the two places. We know,

• For 1° longitudinal difference, the time difference is 4 minutes
• For 82° longitudinal difference, time difference is = 82 x 4 minutes = 328 minutes
• For 30′ or 30 minutes longitudinal difference, the time difference is 2 minutes

∴ The total difference in time

= 328 minutes + 2 minutes
= 330 minutes
= 5 hours 30 minutes

Step 3: The local time in London will be behind that of India because London is located due west of India.

Step 4: If the local time in India is 23 hours 30 minutes, then, the local time in London will be: 23 hours 30 minutes 5 hours 30 minutes = 18 hours or 6 p.m.

Therefore, the programme started at 6 p.m. in London.

Question 6. What is the method for determining the longitude of a place on the Earth?
Answer:

Longitude of a place on the Earth:

To determine the longitude of a place, for example, we have to draw a line from the point of intersection (of the Equator and the meridian of that place.) i.e., B, to the Earth’s centre (O).

• Similarly, another line from the intersection point (of Prime Meridian and the Equator) A to the centre of the Earth, O is drawn.
• The angle ZAOB formed between these two lines on the equatorial plane is the longitude of point Z.
• According to the diagram, the angular distance is 80°. As point Z is located due east of the Prime Meridian, the longitude of that point is 80°E.

Question 7. What is the importance of Prime Meridian?
Answer:

The importance of Prime Meridian are-

1. Determining the hemisphere in which a place is located:

• The Prime Meridian divides the Earth into two equal halves- the Eastern Hemisphere and the Western Hemisphere.
• Places located due east of the Prime Meridian are in the Eastern hemisphere and those due west of the Prime Meridian are in the western hemisphere.

2. Determining the longitude of a place:

The longitude of a place on the Earth’s surface is determined by its angular distance east or west of the Prime Meridian.

3. Determining the standard time of a place:

For convenience in carrying out activities at an international level, all the countries across the globe calculate their standard time with reference to the local time of Prime Meridian i.e. the Greenwich Mean Time.

Question 8. State the importance of the meridians of longitude.
Answer:

The importance of the meridians of longitude are-

1. Determining the location of a place:

The location of a place is determined by its angular distance from the centre of the Earth, east or west of the Prime Meridian.

2. Determining the local time of a place:

All the places located on a meridian experience sunrise, noon and sunset at the same time. So, the local time of a place can be easily determined with the help of a meridian.

3. International Date Line:

• The imaginary line more or less the same as the 180° meridian but not a straight line is known as the International Date Line.
• If we cross the date line from the eastern hemisphere to the western hemisphere, we subtract a day from our calendar while we add a day to it when we cross the date line from the western hemisphere to the eastern hemisphere.

Question 9. Narrate the experience of travelling around the Earth along the Equator and any meridians.
Answer:

Travelling around the Earth along the Equator:

• The Earth rotates around its axis from west to east and it completes one rotation or 360° in 24 hours or 1 day.
• If an observer travels around the Earth along the Equator, he/she has to cross the meridians.
• The difference in time for 1° longitude is 4 minutes due to the Earth’s rotation.
• So, the observer will gain an experience of change in time while travelling around the Earth along the Equator.

Travelling around the Earth along any meridian:

As the intensity of the sun rays gradually decreases from the Equator towards the Poles, the weather becomes cooler. Thus if we travel from the Equator to the Poles along any meridian, a change in weather (from hot to cold) is observed.

Question 10. What is meant by Indian Standard Time (IST)?
Answer:

Indian Standard Time (IST):

• India, a country in the eastern hemisphere has a vast longitudinal extension i.e. from 68°07’E to 97°25′ E. 30 meridians each having their own local time passes through this country.
• As a result, it becomes difficult to carry out activities or services on a national scale. To avoid this problem, the local time of the meridian 821⁄2° E that passes through the city of Allahabad which is more or less in the middle of the country is followed as its standard time.
• This local time is known as the Indian Standard Time (IST).

Question 11. The parallels of latitude are parallel to one another but the meridians of longitude are not.-Explain.
Answer:

The parallels of latitude are parallel to one another but the meridians of longitude are not.

The set of imaginary circular lines drawn horizontally between the Poles parallel to the Equator and to one another are called the parallels of latitude.

• They never meet one another.
• Whereas, the meridians of longitude are a set of imaginary lines drawn vertically from the North Pole to the South Pole.
• These imaginary lines are semi-circular in shape converging at the Poles.
• Thus, they are not parallel to one another irrespective of their lengths being equal.

Question 12. What is meant by meridians of longitude?
Answer:

Meridians of longitude:

• Meridians of longitude are half circles drawn vertically from the North Pole to the South Pole, joining all places within the same longitudinal value. A meridian is half of a great circle.
• All meridians are perpendicular to all parallels of latitude. All meridians are equal in length.
• The meridian of longitude passing through Greenwich with an angular measure of 0° with the Earth’s centre is called the Prime Meridian.

Question 13. Fill up the knowledge live with information about the Royal Observatory in Greenwich.

Answers:

1. The observatory was commissioned in. 1675 with the foundation stone being laid on 10 August.
2. The Prime Meridian passes through this observatory.
3. Since 1924, hourly time signals from the Royal Observatory is broadcast every 5 February.
4. Today, the observatory houses a museum for astronomical and navigational tools.

Question 14. Fill up the knowledge live with information about the Global Positioning System.

Answers:

1. GPS satellites fly in medium Earth orbit at an altitude of approximately 20,200 km above the Earth’s surface.
2. GPS was created and accomplished by the U. S. Department of Defence.
3. At present 31 satellites have been installed by the US Space Force out of which 24 are for general use and rest are used by the U.S. Department of Defence.
4. GPS plays a major role in determining the accurate location of a place.
5. GPS is being used to determine the land use or location of mineral resources, connect mobile networks, transport and communication and many others.

Question 15. They are standing in three different longitudes. Can you say whose time, Sabina’s or Piku’s will be ahead or behind of Mandira’s?

 

Answer: According to the picture, Sabina’s time is ahead of Mandira, because she is at a position due east of Mandira. On the other hand, Pinku’s position being west with respect to Mandira is behind in time.

Question 16.

 

Down:

1. The point which is diametrically opposite to a place on the Earth’s surface.
2. The place where the Royal Observatory is located.
4. This is formed due to the intersection of parallels and meridians.

Across:

2. Small replica of the earth.
3. Angular distance of a place measured in degrees, with respect to the Equator.
5. The nearest star from the Earth, other than the Sun.
6. The instrument used to calculate the local time of a place by observing the Sun’s altitude.

Answers:

Down: 1. ANTIPODE, 2. GREENWICH, 4. GRID
Across: 2. GLOBE, 3. LATITUDE 5. PROXIMA CENTAURI, 6. SEXTANT

Question 17.

 

Down:

1. The time of a place expressed with reference to the Sun’s position on the meridian passing through it.
3. The Meridian is also known as the fixed meridian or zero meridians.

Across:

1. Angular distance of a place lying on either side of the Prime Meridian.
2. All parallels are of this shape.
4. The time of a place is calculated with reference to the Greenwich Mean Time.

Answers:

Down: 1. LOCAL TIME, 3. PRIME
Across: 1. LONGITUDE 2. CIRCULAR, 4. STANDARD TIME

Question 18. What is the role of the Sextant and Marine Chronometer in determining the location of any place or determining the location of any ship in danger at mid-sea?
Answer:

Marine Chronometer is a precise and accurate clock, used to determine the longitude of any place by means by celestial navigation and Sextant is an instrument used to determine the latitude of any place by measuring the altitude of the Sun at that place.

• Every ship carries a Chronometer and Sextant. So that sailors can measure the longitude and the latitude of the place at which the ship is located.
• The sailors of the ship which is in danger at mid-sea, thus measure the latitude and longitude of that place and transmit this information by radio to the nearest ship or port asking for help.
• This information helps the rescue team to reach the spot quickly.

Question 19. What is the exact location of a point you have marked on the ball?
Answer:

• It is not possible for us to tell the exact position of the point drawn on a ball.
• Since there is no fixed point on the ball, with respect to which distance of a point can be measured.
• Turning the ball again changes the position of the point east or west, north or south, up or down on the ball.
• As a result, the exact position of the point drawn on the ball cannot be stated.

Important Definitions Related to Meridians of Longitude

Question 20. Prepare a list of different places situated on the same meridian from the atlas.
Answer:

Here we list different cities on the atlas along the 0° meridian or the Prime Meridian.

Question 21. Determine the latitudinal and longitudinal location on the globe.

Answer:

Question 22. Find the locations of the marked points on the globe.

Answer:

Question 23. Cut a piece from a watermelon as shown in the figure. Is the concept of latitude available from this figure?

Answer:

• Cutting a watermelon with a knife according to the picture gives an idea of latitude. Removing the cut piece creates a triangular space.
• The innermost part of the hollow portion is considered to be the centre of the watermelon as well as the centre of the Earth.
• The plane along the centre is the equatorial plane.
• The angle at the centre of the equatorial plane of the Earth with the vertex above is the value of the latitude of that vertex (∠).

Question 24. Draw parallels of latitude and meridians of longitude on the world map.
Answer:

Parallels of latitude and meridians of longitude on the world map-

Question 25. Create a small earth for yourself by drawing two poles and the parallels of latitude on a ball.
Answer:

A small earth is made by a ball-

WBBSE Chapter 2 Determination Of The Location Of A Place On The Earth Surface Topic B Meridians Of Longitude Short Question And Answers

Question 1. What is the time difference for 1° longitude?
Answer:

Time difference for 1° longitude:

• The time difference for 1° longitude is 4 minutes. As our Earth is a sphere, the sum total of the angular measures of all the meridians is 360°.
• It takes 24 hours (24 x 60 minutes) or 1440 minutes to complete one rotation.
• So, to cover an angular distance of 1° it takes 4 minutes (1440 minutes ÷ 360).

Question 2. It is very easy to describe the location of a house in a locality. But how can you explain the location of that house as a place on the Earth’s surface?
Answer:

• The exact location of a place on the surface of the Earth is easily understood by the name of the place, district, state, country, continent and hemisphere.
• However, to be more precise, the location of the place is determined by the intersecting coordinate of the parallel and meridian passing over it.

Question 3. What is meant by local time?
Answer:

Local time:

• The time in a particular place calculated by the Sun’s transit over the meridian passing through that place is referred to as its local time.
• This local time is also known as the Sun time because it is calculated with respect to the Sun being overhead at a particular meridian, which is the noon for that meridian.
• Places located on different meridians have different local times.

Question 4. What is meant by standard time?
Answer:

Standard time:

• Places situated on different meridians have different local times.
• Several meridians pass through every country. If their local time are considered then the proper functioning of the national services like railways, airways, and postal department in the country would get hindered.
• So, to remove this hindrance, the local time of a central meridian is taken as the time for the whole country.
• This meridian passes more or less through the Middle of the country and its local time is referred to as the standard time of that country.

Example: The central meridian of India, 82½° E passes through the city of Allahabad and its local time is known as the Indian Standard Time (IST).

Question 5. What is Greenwich Mean Time or International Standard Time?
Answer:

Greenwich Mean Time or International Standard Time:

Greenwich Mean Time (GMT) is the local time of the meridian passing through Greenwich near London.

• As different countries have different standard times, it becomes difficult to carry out international communications.
• To avoid this problem, Greenwich Mean Time is followed across the globe as the International Standard Time.
• Countries located due east of the Prime Meridian are ahead of the GMT while those due west are behind GMT.

Question 6. What is the difference in local time
Answer:

Difference in local time:

The longitude of Kolkata is 88°30′ East. The longitude of Dhaka is 90° East.

∴ The longitudinal difference between Kolkata and Dhaka is (90°-88°30′)= 1°30′ We know, for 10 or 60′ longitudinal difference, a time difference of 4 minutes occurs.

∴ For 1′ longitudinal difference, the time difference will be 4 seconds.

∴ For 30′ longitudinal difference, the time difference will be 30 x 4 seconds = 120 seconds 2 minutes.

∴ For a 1°30′ longitudinal difference, the total time difference will be (4+2) minutes = 6 minutes.

Question 7. Define time zone.
Answer:

Time zone:

• Countries with wide east-west extensions have a large number of meridians passing through them which results in difficulty in administration according to the local time of any one meridian.
• To solve this inconvenience, the Earth has been divided into 24 zones of a 1-hour time span at every 15° interval.
• These are called time zones. For example, the United States of America and Russia have 4 and 11 time zones respectively.

Question 8. What is Prime Meridian?
Answer:

Prime Meridian:

• The meridian passing through the Royal Observatory at Greenwich near London, having an angular measure of 0° is called the Prime Meridian.
• It divides the Earth in two equal halves-the eastern hemispheres and the western hemisphere.

Question 9. What are the three important characteristics of the Prime Meridian?
Answer:

The three important characteristics of the Prime Meridian are-

1. Orientation: The Prime Meridian runs from the North Pole to the South Pole.

2. Shape: The Prime Meridian is semi-circular.

3. Hemisphere: The Prime Meridian divides the Earth into two equal halves-the eastern and the western hemispheres.

Question 10. What are longitudes?
Answer:

Longitudes:

• The longitude of a place is the angular distance of that place east or west of the Prime Meridian from the centre of the Earth.
• All the longitudes to the east of the Prime Meridian are denoted by the letter E, while those on the west are denoted by the letter W.

Question 11. Why are the lines of longitudes also known as the ‘meridians’?
Answer:

• The lines that connect all the points on the surface of the Earth that are equidistant from the Prime Meridian having the same longitudinal values are called meridians or ‘lines of longitude’.
• This word originates from the Latin word ‘meridian’ meaning ‘noon’. This is because the Sun is directly overhead a meridian at noon.
• Noon time at a particular line of longitude is the reference point for determining the local time at that place. So, they are also called ‘meridians’.

Question 12. What are the important characteristics of meridians?
Answer:

The important characteristics of meridians are-

1. Orientation: The meridians run from the North Pole to the South Pole.
2. Shape: Every meridian is a half circle.
3. Length: All the meridians are equal in length.
4. Angular measurement: Each meridian forms an angle of 180°.

Question 13. Categorise the lines of meridians.
Answer:

The different lines of meridians are-

1. Meridians towards the east: The meridians extend from the Prime Meridian (0°) to 180° (eastwards).
2. Meridians towards the west: The meridians extend from the Prime Meridian (0°) to 180° (westwards).
3. 180° meridian: The 180° east and the 180° west meridians are actually the same meridian.

Question 14. At which place can a person stand on both the eastern and the western hemispheres simultaneously? Or, Where can you see the eastern and the western hemispheres simultaneously?
Answer:

• At Greenwich, a person visiting the British Royal Observatory can stand on both the eastern and the western hemispheres simultaneously by placing his feet on either side of the Greenwich Mean Line (0°).
• Similarly, both hemispheres can be seen if one stands on the 180° meridian.

Question 15. The longitude of Kolkata is 88°30′ east. -Explain.
Answer:

The longitude of Kolkata is 88°30′ east:

• The longitude of a place is its angular distance east or west of the Prime Meridian as measured from the centre of the Earth.
• The angular distance of the longitude passing through Kolkata with respect to the Prime Meridian is 88°30′ east, i.e.
• Kolkata is located in the eastern hemisphere. Hence, we say that the longitude of Kolkata is 88°30’E.

Question 16. “The location of a place is 30°20′ east and 18°22′ south.”-What do you mean by this?
Answer:

“The location of a place is 30°20′ east and 18°22′ south.”:

• The location of a place is 30°20′ east and 18°22′ south means that the location of that place on the Earth’s surface is at the intersection point of the meridian situated 30°20′ due east of the Prime Meridian and the parallel situated 18°22′ due south of the Equator.
• This intersection point lies in the southeastern hemisphere.

Question 17. What is the time difference between the Greenwich Mean Time and the Indian Time and Standard Time?
Answer:

• The angular measure of the meridian passing through Greenwich near London is 0° and that of the standard meridian of India is 82°30′ east.
• Therefore India being located 82°30′ east of the Greenwich Meridian (0°) will be ahead of the Greenwich Mean Time (GMT) by 330 minutes i.e., 330÷60 = 5 hours 30 minutes.
• So, there is a time difference of 5 hours and 30 minutes between the Greenwich Mean Time and the Indian Standard Time.

Question 18. Why is the local time of all places the same on the same meridian?
Answer:

• The Earth takes 24 hours to rotate around its axis, from west to east.
• As a result, each meridian receives vertical sun rays when it comes in front of the Sun.
• This is the time when the Sun is directly overhead at all the places on that meridian and the local time becomes noon.
• Hence, the local time is the same places at all on the same meridian.

Example: The local time of all the places on the 82°30’E meridian is the same.

Question 19. There is a change in local time with the change in meridian.- Why?
Answer:

There is a change in local time with the change in meridian:

• The meridians are imaginary semi-circular lines oriented in a north-south direction.
• As the Earth completes one rotation in 24 hours, all the meridians are brought under the Sun in succession in this specified time interval.
• The Sun’s transit over a meridian determines the local noon time of all the places located on it.
• So as every meridian experiences noon at a different time in 24 hours, there is a change in local time with the change in meridian.

Question 20. In which direction of the Earth, does the time increase and why?
Answer:

• The Earth rotates from west to east. So, the Sun rises in the east and sets in the west.
• That is why, places that are located due east, experience sunrise, noon and sunset in advance.
• As a result, out of two places, the place which is due east to the other place is ahead of time.
• Hence we can say that towards the eastern direction of the Earth, the time increases.

Question 21. Ram      Shyam     Yadu
                       0°  ←      10° E   → 20° E
                      ?      ←     Noon  →?
Who is ahead in time with respect to Shyam? Explain.
Answer:

Yadu is ahead in time with respect to Shyam and Ram, because he is at a position due east of Shyam and Ram. Whereas Ram’s position being west with respect to Shyam and Yadu is behind in time.

WBBSE Chapter 2 Determination Of The Location Of A Place On The Earth Surface Topic B Meridians Of Longitude Very Short Question Answers

Question 1. What do we call the angular distance of a place located east and west of the Prime Meridian?
Answer: Longitude.

Question 2. What are the lines of longitude also known as?
Answer: Meridians.

Question 3. Which is the line that passes in a north-south orientation through the British Royal Observatory?
Answer: The Prime Meridian.

Question 4. What is the Prime Meridian also known as?
Answer: Greenwich Meridian.

Question 5. What is the time difference for every 1° difference in longitude?
Answer: 4 minutes.

Question 6. What is the local time at a longitude passing through the centre of a country called?
Answer: Standard time.

Question 7. What is the term for the time of a place with reference to the Sun’s position on the meridian passing through it called?
Answer: Local time.

Question 8. What is the suffix added to the time within the period 12 o’clock at noon and 12 o’clock at midnight?
Answer: p.m.

Question 9. What is the suffix added to the time within the period 12 o’clock at midnight and 12 o’clock at noon the next day?
Answer: a.m.

Question 10. What is the angular value of the standard meridian of India?
Answer: 82° 30′ E.

Question 11. Which time is referred to across the globe as the International Standard Time?
Answer: Greenwich Mean Time.

Question 12. What is the time difference between the Indian Standard Time and the Greenwich Mean Time?
Answer: 5 hours 30 minutes.

Question 13. Which technology helps us to find the latitude and longitude of a place on the Earth’s surface at any time of the day?
Answer: GPS.

Question 14. What is the name for the point that is diametrically opposite to a place on the Earth’s surface?
Answer: Antipode.

Question 15. Which instrument is used to determine the time at Greenwich?
Answer: Chronometer.

Question 16. Which instrument is used to calculate the local time of a place by observing the Sun’s altitude?
Answer: Sextant.

Question 17. I am an imaginary line on the Earth’s surface equidistant from the two Poles dividing the Earth into two equal halves-the northern and the southern hemispheres. Who am I?
Answer: Equator

Question 18. We are a set of circular lines running in the east-west direction which extend from east to west across the globe. Who are we?
Answer: Parallels

Question 19. I am an imaginary circular line located 232° north of the Equator. Who am I?
Answer: Tropic of Cancer

Question 20. I am an imaginary circular line located at 23% south of the Equator. Who am I?
Answer: Tropic of Capricorn

Question 21. In both hemispheres, the meridians converge at us. Who are we?
Answer: North and South pole

Question 22. I am an imaginary line passing through Greenwich (east of London), oriented in a north-south direction. Who am I?
Answer: Prime Meridian

Question 23. We are semi-circular imaginary lines having a north-south orientation. Who are we?
Answer: Meridians

Question 24. We divide the Earth into two halves- the eastern and the western hemispheres. Who are we?
Answer: Prime Meridian (0°) and International Date Line (180°)

Question 25. I am an imaginary semi-circular line passing through a place whose standard time is 24 hours ahead of Greenwich Mean Time. Who am I?
Answer: 180°

Question 26. The location of a place on the Earth’s surface is determined by the point of our intersection. Who are we?
Answer: Parallels and Meridians

Question 27. When we look at a globe or a map in the atlas, we find some horizontal and vertical lines on the map. Now what are these lines?
Answer:

On the globe or a map in the atlas, the. horizontal lines are called parallels of latitude and the vertical lines are called meridians of longitude.

Question 28. What do a.m. and p.m. mean?
Answer:

a.m. and p.m.:

A.M. (Ante Meridian i.e. ‘before midday’) and p.m. (Post Meridian i.e. after midday) are suffixes used to denote the time from midnight to noon and from noon to midnight respectively.

WBBSE Chapter 2 Determination Of The Location Of A Place On The Earth Surface Topic B Meridians Of Longitude Fill In The Blanks

Question 1. An imaginary line passing through Greenwich having a north-south orientation is called _________.
Answer: The Prime Meridian

Question 2. The parallels of latitude intersect the meridians of longitude _________.
Answer: Perpendicularly

Question 3. The meridians of longitude intersect the parallels of latitude at an angle of _________.
Answer: 90°

Question 4. For determining the location of a place, angular measures of both _________ and parallels are required.
Answer: Meridians

Question 5. The location of a place is determined with the help of the point of intersection of the _________ and the _________.
Answer: Latitude, longitude

Question 6. The angular measure of longitudes begins from _________ degrees.
Answer: 0

Question 7. The angular measure of longitudes extends up to _________ degrees.
Answer: 180

Question 8. The angular measure of a meridian is calculated with respect to the _________.
Answer: Prime Meridian

Question 9. The longitude of _________ passes through Kolkata.
Answer: 88°30’E

Question 10. The meridian of _________ east and west is a common line.
Answer: 180°

Question 11. The _________ Line is located opposite to the Prime Meridian.
Answer: International Date

Question 12. The total number of meridians drawn across the globe is _________.
Answer: 360

Question 13. 1°= _________ minutes.
Answer: 60

Question 14. The time difference for 1° longitude is _________ minutes.
Answer: 4

Question 15. _________ will change if one walks towards the east or the west from the Prime Meridian.
Answer: Time

Question 16. The time difference between Indian Standard Time and Greenwich Mean Time is _________.
Answer: 5 hours 30 minutes

Question 17. The distance between any two meridians is _________.
Answer: Variable

Question 18. The linear distance between any two meridians at the Equator is _________.
Answer: 111 km

Question 19. _________ is calculated by observing the maximum vertical angle of the Sun.
Answer: Local time

Question 20. The clock measuring the time at Greenwich is called the _________.
Answer: Chronometer

Question 21. The instrument used to measure the vertical angle of the Sun is called ________.
Answer: Sextant

Question 22. The time difference between any two places is determined by their longitudinal values.
Answer: True

Question 23. The meridian adopted as the central meridian of India for calculating the Indian Standard Time (IST) is 881⁄2° E.
Answer: False

Question 24. The meridians are also known as latitudes.
Answer: False

Question 25. The Royal Observatory, Greenwich is situated in London.
Answer: True

Question 26. The angular measure of longitudes extends up to 90°.
Answer: False

Question 27. The International Date Line is a meridian defined to be 180°.
Answer: True

Question 28. The local time at Allahabad is referred to as the Indian Standard Time (IST).
Answer: True

Question 29. The local time of a place is determined concerning the parallels of latitude.
Answer: False

Question 30. The Prime Meridian is also referred to as the International Date Line.
Answer: False

Question 31. All meridians are half-circles.
Answer: True

Question 32. 180° east longitude and 180° west longitude are two different meridians.
Answer: False

Question 33. The lengths of all meridians are not equal.
Answer: False

Question 34. The GPS or Global Positioning System is a modern technique that helps to determine the location of a place.
Answer: True

Question 35. The Prime Meridian helps us to determine the northern and southern location of a place.
Answer: False

WBBSE Chapter 2 Determination Of The Location Of A Place On The Earth Surface Topic B Meridians Of Longitude Find The Odd One Out

Question 1. Equator: Arctic Circle: Prime Meridian: Antarctic Circle
Answer: Prime Meridian (not a full circle)

Question 2. 1 hour: 1° 1′ 1″
Answer: 1 hour (not a unit of latitude and longitude)

Question 3. 1 hour: 1°: 1 minute: 1 second
Answer: 1° (not a unit of time)

Question 4. Local Time: School time: Standard Time: Greenwich Mean Time
Answer: School time (not a measurement of geographical time)

WBBSE Chapter 2 Determination Of The Location Of A Place On The Earth Surface Topic B Meridians Of Longitude Correct The Following

Question 1. The Equator runs north-south through the middle of the Earth.
Answer: East-west

Question 2. The Prime Meridian runs through the River Thames.
Answer: Greenwich

Question 3. The Prime Meridian divides the Earth into the northern and southern Hemispheres.
Answer: Eastern and western

Question 4. The lines running from the North Pole to the South Pole are known as latitudes.
Answer: Meridians of Longitude

Question 5. The Royal Astronomical Observatory is located in the city of Reading near London in the United Kingdom.
Answer: Greenwich

Question 6. The Earth needs 4 seconds to cover 1° of longitudinal distance.
Answer: 4 minutes

WBBSE Chapter 2 Determination Of The Location Of A Place On The Earth Surface Topic B Meridians Of Longitude Scrambled Words

1. TORUAEQ
2. PICCAPCORIRNTROOF
3. TUNLOGIDE
4. LENORPOTH
5. PHEHEMISRE
6. NEPLAEQTOUARIAL

Answers:

1. EQUATOR
2. TROPIC OF CAPRICORN
3. LONGITUDE
4. NORTH POLE
5. HEMISPHERE
6. EQUATORIAL PLANE

WBBSE Chapter 2 Determination Of The Location Of A Place On The Earth Surface Topic B Meridians Of Longitude Match The Columns

Question 1.

Answer: 1. B, 2. D, 3. E, 4. C, 5. A

Question 2.

Answer: 1. E, 2. D, 3. A, 4. B, 5. C