Written as per the latest syllabus prescribed by the Maharashtra State Bureau of Textbook Production and Curriculum Research, Pune.

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1 Written as per the latest syllabus prescribed by the Maharashtra State Bureau of Textbook Production and Curriculum Research, Pune. STD. VIII Geography Salient Features Written as per the new textbook. Short overview for a quick glimpse of the chapter. Complete chapter coverage through a variety of questions. Map-based questions for better geographical understanding. Chapter-wise assessment with every chapter for knowledge testing. Printed at: India Printing Works, Mumbai Target Publications Pvt. Ltd. No part of this book may be reproduced or transmitted in any form or by any means, C.D. ROM/Audio Video Cassettes or electronic, mechanical including photocopying; recording or by any information storage and retrieval system without permission in writing from the Publisher. TEID: 12680_JUP P.O. No

2 Contents No. Topic Name Page No. 1 Local Time and Standard Time 1 2 Interior of the Earth 12 3 Humidity and Clouds 23 4 Structure of Ocean Floor 36 5 Ocean Currents 48 6 Land Use 57 7 Population 67 8 Industries 83 9 Map Scale Field Trip 112 Note: Textual exercise questions are represented by * mark.

3 1 Local Time and Standard Time An Overview Mode of measuring time in olden days: Various natural events as well as instruments like Ghatikapaatra, sand timer, etc. Apparent movement of sun: Since, earth rotates from west to east, we feel that the sun is changing its position from east to west daily. Local time is the time of place as decided by the location of sun in the sky. Local time of a place on the earth s surface is determined with the help of its noon time. Since, noon time is same for a given longitude across the earth i.e. form the North Pole to the South Pole, the places lying on the same longitude will have same local time. The time from midnight to noon is denoted by a.m. (Ante Meridiem) while the time from noon to midnight is denoted by p.m. (Post Meridiem) Longitudes to the east of a particular longitude are ahead of time of that particular longitude, while the longitudes to the west are behind that time. The Indian Standard Time (IST) has been decided according to the 8230 E longitude which passes through Mirzapur, near Allahabad in Uttar Pradesh. International Standard Time, also known as Greenwich Mean Time (GMT), is based on the local time at the 0 longitude also known as Prime Meridian which passes through the Greenwich city in England. The Indian Standard Time (IST) is 5 hours 30 mins ahead of Greenwich Mean Time (GMT). 1

4 Std. VIII: Geography Choose the correct alternative *1. The earth requires 24 hours for one rotation. In one hour, (A) 5 longitudes will face the sun (B) 10 longitudes will face the sun (C) 15 longitudes will face the sun (D) 20 longitudes will face the sun *2. To calculate the difference between the local times of any two places on the earth, (A) the noon time at both the places should be known (B) the difference in degrees of their longitudes should be known (C) the difference in standard times of both the places should be known (D) changes need to be made according to International Date Line. *3. The difference between the local time of any two consecutive longitudes is (A) 15 minutes (B) 04 minutes (C) 30 minutes (D) 60 minutes 4. The Earth rotates from (A) east to west (B) north to south (C) south to north (D) west to east 5. As soon as the sun starts moving up in the sky after sunrise, (A) the length of the shadow reduces (B) the length of the shadow increases (C) the length of the shadow remains the same (D) the length of the shadow is the longest 6. In the regions, the daytime could be more than 24 hours depending upon the season. (A) lying in between 5 North and South of equator (B) lying in between Tropic of Cancer and Tropic of Capricorn 1 (C) lying between 23 1 and 66 towards (D) the North and South of the equator lying in between the polar circles and the poles 7. The time of a place as decided by the location of the sun in the sky is known as (A) Standard time (B) Local time (C) Greenwich Mean Time (D) Coordinated Universal Time 8. The local time of a place on the earth s surface is determined with reference to its time. (A) sunrise (B) sunset (C) noon (D) midnight 9. Longitudes lying to the of any longitude are ahead of the time. (A) north (B) south (C) east (D) west 10. The Indian Standard Time (IST) has been decided according to. (A) the Tropic of cancer which passes the middle of India at 2330N (B) the location of the sun in the sky (C) natural events and instruments like Ghatikapaatra and sand timer (D) 8230 E longitude which passes through Mirzapur near Allahabad in Uttar Pradesh. 11. The difference in standard times of various countries is calculated with reference to (A) Local Standard Time (B) IST (C) GMT (D) BRT 12. The Indian Standard Time is (A) 5 hours 30 minutes behind GMT (B) 2 hours 45 minutes behind GMT (C) 5 hours 30 minutes ahead of GMT (D) 3 hours ahead of GMT Answers: 1. (C) 2. (B) 3. (B) 4. (D) 5. (A) 6. (D) 7. (B) 8. (C) 9. (C) 10. (D) 11. (C) 12. (C) Right or Wrong. If wrong, write the correct sentence 1. The apparent movement of the sun is from east to west. 2. The shadows at the noon are the longest. 3. The time of a place as decided by the location of the sun in the sky is known as its standard time. 4. The local time of a place is calculated with reference to the time at the Prime Meridian. 5. Normally, if the difference between the latitudinal extent of a country is less than one or two hours, only one standard time is considered for the country.

5 6. The Indian standard Time has been decided according to 2330N latitude which passes through the middle of the country Answers: 1. Right 2. Wrong The shadows in the early morning and evening are the longest while those at the noon are the shortest. 3. Wrong The time of a place as decided by the location of the sun in the sky is known as its local time. 4. Right 5. Wrong Normally, if the difference between the longitudinal extent of a country is less than one or two hours, only one standard time is considered for the country. 6. Wrong The Indian standard Time has been decided according to 8230 E longitude which passes through the middle of the country. 1. Group A i. Greenwich Mean Time ii. Indian Standard Time iii. Time Zones in the world 2. Match the Following Group B a. 180 Meridian b. 24 c E longitude d. Prime Meridian Group A Group B i. Local Time a. Greenwich Mean Time ii. Standard Time b. determined by location of sun in sky iii. International c. time at longitude Standard Time which generally passes through the middle of the country d. International Date line Answer: 1. (i d), (ii c), (iii b) 2. (i b), (ii c), (iii a) Chapter 1: Local Time and Standard Time Diagram based question *1. Write the situations of place A shown in these diagrams in the boxes below them: i. Sunrise ii. Midnight iii. Noon iv. Sunset i. ii. A iii. Ans: i. Midnight ii. Sunset iii. Sunrise iv. Noon *1. If it is 10 pm on 21 st June at Prime Meridian, write the dates and time at A, B and C in the table. Place Longitude Date Time A 120 E B 160 W C 60 E Ans: A Complete the table Place Longitude Date Time A 120 E 22 nd June 6.00 am B 160 W 21 st June am C 60 E 22 nd June 2.00 am Answer in one sentence 1. What is daytime? Ans: The part of the day from sunrise to sunset is considered as daytime. 2. What is night-time? Ans: The part of the day from the sunset to the next sunrise is considered as night-time. 3. Which instruments were used in older days to measure time? Ans: In older days, time was measured with the help of natural events as well as instruments like Ghatikapaatra, sand timer etc. iv. A A 3

6 Std. VIII: Geography 4. In which regions on the earth, the daytime could be more than 24 hours? Ans: In the regions lying between the polar circles and the poles, the daytime could be more than 24 hours. 5. What do you mean by a.m.? Ans: While telling the time between midnight and noon, we put a.m. in front of the time, which means Ante Meridiem. 6. What is p.m.? Ans: The time in between noon and midnight is denoted by p.m. which means Post Meridiem. 7. What will be the impact of different local times within a country? Ans: If there are different local times within a country then there will be lack of synchronization in the routine activities of the country. 8. On the basis of which longitude is the Indian Standard Time decided? Ans: The Indian Standard Time (IST) has been decided according to the 8230 E longitude which passes through Mirzapur, near Allahabad in Uttar Pradesh. 9. The local time of which longitude is considered as International Standard Time? Ans: The local time at Greenwich (0 Meridian) i.e., Greenwich Mean Time in England is considered to be the International Standard Time. 10. What is the time difference between IST and GMT? Ans: The Indian Standard Time (IST) is 5 hours and 30 minutes ahead of Greenwich Mean Time (GMT). Answer in brief 1. What do you mean by local time? Ans: i. The time of a place as decided by the location of the sun in the sky, is known as its local time. ii. The local time of a place on the earth s surface is determined with reference to its noon time. iii. Thus, the places lying on the same longitude have the same local time. 2. What do you mean by standard time? Ans: i. The time assumed according to the central meridian of a country is called its standard time. ii. This time is determined on the basis of the longitude passing through the centre of the country and all the places in a country use this time What is Indian Standard Time? Ans: i. The Indian Standard Time (IST) is the standard time of India. It has been decided according to the 8230 E longitude which passes through Mirzapur (near Allahabad in Uttar Pradesh). ii. This longitude passes through the middle of the country and the local time at this longitude is considered as the standard time of the whole country. 4. Explain the rotation of earth and the relative location of the sun with the help of neat and labelled diagram. Ans: Midnight Sunset Sunrise Noon i. The Earth takes 24 hours i.e., one day to complete one rotation. ii. As the Earth rotates from west to east, it appears that the sun rises in the east. iii. As a result, we experience sunrise, noon, sunset and midnight. iv. During rotation, the longitudes in the western part of the earth face the sun gradually while those in the east experiences darkness. v. The longitude which faces the sun experiences sunrise and eventually noon, while the one in darkness experiences sunset and eventually midnight. *5. How is the standard time of a place determined? Ans: i. If different local times are followed within a country according to the longitudinal differences, then there will be lack of synchronization in the routine activities in the country. ii. If each place follows their local time, it could lead to discrepancies in carrying out daily business in the country. iii. In order to avoid this, it is a general practice to consider the local time at the longitude which passes through the middle of the country as the standard time of that country. This time is used all over the country.

7 iv. Only one standard time is considered for the country when the difference between the longitudinal extent of the country is less than one or two hours. v. However, when the longitudinal extent is more than that then one standard time is not enough and in such countries, more than one standard time zones are considered. Give Geographical Reasons *1. The local time is decided by the noon time. Ans: i. Longitudes help in determining the time of a place. ii. The time of a place as decided by the location of the sun in the sky, is known as its local time. iii. The local time of a place on the earth s surface is determined with reference to its noon time. iv. This implies that places lying on the same longitude, from the North pole to the South pole, have the same local time. *2. The local time at Greenwich is considered to be the international standard time. Ans: i. Businesses is conducted at global level, when there is compatibility between the standard times of various countries. ii. In order to facilitate this, the world has been divided into 24 time zones, which have been created with reference to the Prime Meridian that passes through Greenwich. iii. The local time at Greenwich (Greenwich Mean Time) in England is considered to be the International Standard Time for international coordination between countries. iv. The difference in standard times of various countries is calculated with reference to GMT. *3. The Standard time of India has been decided by the local time at 82.5 E (8230 E) longitude. Ans: i. If there are different local times within a country because of longitudinal differences, then there will be a lack of synchronisation in the routine activities in the country. Chapter 1: Local Time and Standard Time ii. Therefore, the local time at the longitude which generally passes through the middle of the country is deemed to be the standard time of that country. iii. The longitude of 82.5 E (8230 E) passes through the middle of India with reference to its longitudinal extent, through the city of Mirzapur near Allahabad in Uttar Pradesh. iv. Also, the difference between the local times of any other place in India and that of 8230 E, is not more than one hour. Hence, the Indian Standard Time (IST) has been decided according to the local time at 82.5 E (8230 E) longitude. *4. Canada has 6 different standard times. Ans: i. Normally if the difference between the longitudinal extent of the country is less than one or two hours, only one standard time is considered for the country. ii. But if the longitudinal extent is more than that, then one standard time is not enough and in such countries, more than one standard time zones are considered. iii. The longitudinal extent of Canada is approximately 90 longitudes. iv. Thus the time difference between the eastern most and the western most part of Canada will be 6 hours. Hence, Canada has 6 different standard times. 5. The length of the shadow cannot be considered for telling the noon time at the poles. Ans: i. In the regions lying in between the polar circles and the poles the daytime could be more than 24 hours depending upon the season. ii. As a result, understanding the timings of sunrise, noon, sunset and midnight becomes important. iii. At the poles, the daytime and the duration of the day lasts around 6 months. iv. When the sun rises on a specific day, it moves around the horizon and the shadow formed due to this can remain for a long time. Hence, the length of the shadow cannot be considered for telling the noon time at the poles. 5