Chapter 1 geography of Class 9 is about India. Important questions from this chapter are given below.

Location

Extend of the land

Latitude – 8°4’N and 37°6’N

Longitude – 68°7’E and 97°25’E

Tropic of Cancer – 23°30’N – divides the country into two equal parts

South east – Bay of Bengal, Andaman Nicobar Islands

South west – Arabian sea, Lakshadweep

Southern most point of Indian union – Indira Point

Southern most point of Indian mainland – Kanyakumari

Size

Land mass of India – 3.28 million square km

2.4% of the total geographical area of the world

7^th largest country in size

Land boundary – 15,200 km

Total length of coast line – 7,516.6 km

2^nd largest country in population

1. Why 82°30’E has been selected as the standard meridian of India?

India’s standard meridian (82°30’E) runs north-south through nearly the middle of the country. It passes through Mirzapur in Uttar Pradesh. Having a standard time for the entire country is essential to avoid confusion. This standard time is usually the time at the standard or central meridian of the country. Each meridian has its own local time which is the sun time at a particular place. Since Mirzapur lies in the middle of the eastern and western longitudinal extremes of the country, its standard meridian (82°30’E) is considered as the standard meridian of the country.

India is a large country that extends east-west for about 30° of longitude. At any given point of time, the local time at these 30 meridians is different. There is usually a time lag of 2 hours from Gujarat in the west to Arunachal Pradesh in the east. Since having a different time in different parts of the country will lead to a lot of confusion, the central meridian which passes through Mirzapur in UP is considered as the standard meridian and the local time of this meridian is taken as IST and accepted all over the country.

Calculation of time

Earth rotates on its axis in 24 hours. During this time is covers 360 degrees. Each degree of longitude covers 4 minutes. Greenwich mean time refers to 0 degree longitude passing through London. The central meridian of India is 82°30’E. When multiplied by 4 minutes,it comes to be 330 minutes or 5 hours 30 minutes. So, Indian Standard Time (IST) = GMT + 5 hour 30 minutes.

2. In Kanyakumari, there is hardly any difference in the duration of day and night whereas in Kashmir, this is not the case. Why?

The distance between the southern and northern most point of India is over 3500 kilometers. It is this distance that affects the length of day and night in Kanyakumari and Kashmir.

Kanyakumari is close to the equator. Here the sunrays fall vertically almost throughout the year. Hence the days and nights are of equal length. The maximum difference between the length of day and night is hardly 15 minutes.

Kashmir is a long way away from the equator and lies in the temperate zone. Here, sunrays are always inclined. Hence, in summer, the days are longer and nights are shorter whereas in winter, the days are shorter and nights are longer.

3. The central location of India at the head of the Indian Ocean is considered of great significance. Why?

The Indian landmass lies in the centre of east and west Asia. India is a southward extension of the Asian continent. The Trans Indian Ocean connects the countries of Europe in the west and the countries of East Asia. This makes India’s location strategically important.  

The Deccan Peninsula protrudes into the Indian Ocean and helps India to establish a close contact with West Asia, Africa and Europe from the western coast and south east and East Asia from the eastern coast. India has a longer coastline along the Indian Ocean than any other country. That also explains why Indian Ocean is named after India.